<?xml version="1.0" encoding="us-ascii" standalone="yes"?>
<!--XBRL Document Created with XBRLMaster-->
<!--Version: 2.3.08-->
<!--Based on XBRL 2.1-->
<!--Date of creation: 10/07/2026-->
<!--Software architectural design and coding: A'c Dharmapremananda Avt.-->
<!--Copyright (c) 2026 I-NET Business Solutions, Inc. All Rights Reserved.-->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://solarmax.com/role/Cover" xlink:href="solarmax-20260630.xsd#Cover" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CondensedConsolidatedBalanceSheets" xlink:href="solarmax-20260630.xsd#CondensedConsolidatedBalanceSheets" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:href="solarmax-20260630.xsd#CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfOperations" xlink:href="solarmax-20260630.xsd#UnauditedCondensedConsolidatedStatementsOfOperations" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:href="solarmax-20260630.xsd#UnauditedCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfChangesInStockholdersDeficit" xlink:href="solarmax-20260630.xsd#UnauditedCondensedConsolidatedStatementsOfChangesInStockholdersDeficit" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfCashFlows" xlink:href="solarmax-20260630.xsd#UnauditedCondensedConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/DescriptionOfBusiness" xlink:href="solarmax-20260630.xsd#DescriptionOfBusiness" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPolicies" xlink:href="solarmax-20260630.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/DisaggregationOfRevenue" xlink:href="solarmax-20260630.xsd#DisaggregationOfRevenue" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CashCashEquivalentsAndRestrictedCash" xlink:href="solarmax-20260630.xsd#CashCashEquivalentsAndRestrictedCash" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccountsReceivableNet" xlink:href="solarmax-20260630.xsd#AccountsReceivableNet" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/HeldToMaturityDebtInvestments" xlink:href="solarmax-20260630.xsd#HeldToMaturityDebtInvestments" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/ReceivableFromSpicNet" xlink:href="solarmax-20260630.xsd#ReceivableFromSpicNet" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/LargeScaleEpcContracts" xlink:href="solarmax-20260630.xsd#LargeScaleEpcContracts" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CustomerLoansReceivable" xlink:href="solarmax-20260630.xsd#CustomerLoansReceivable" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InventoriesNet" xlink:href="solarmax-20260630.xsd#InventoriesNet" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNet" xlink:href="solarmax-20260630.xsd#OtherReceivablesAndCurrentAssetsNet" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/PropertyAndEquipmentNet" xlink:href="solarmax-20260630.xsd#PropertyAndEquipmentNet" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InvestmentsInUnconsolidatedCompanies" xlink:href="solarmax-20260630.xsd#InvestmentsInUnconsolidatedCompanies" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/FinancingArrangements" xlink:href="solarmax-20260630.xsd#FinancingArrangements" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccruedExpensesAndOtherPayables" xlink:href="solarmax-20260630.xsd#AccruedExpensesAndOtherPayables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/Concentrations" xlink:href="solarmax-20260630.xsd#Concentrations" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AcquisitionContingenciesAndOtherPayableToUononeGroup" xlink:href="solarmax-20260630.xsd#AcquisitionContingenciesAndOtherPayableToUononeGroup" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/RelatedPartyTransactions" xlink:href="solarmax-20260630.xsd#RelatedPartyTransactions" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingencies" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/StockholdersEquityDeficit" xlink:href="solarmax-20260630.xsd#StockholdersEquityDeficit" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/IncomeTaxes" xlink:href="solarmax-20260630.xsd#IncomeTaxes" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/NetIncomeLossPerShare" xlink:href="solarmax-20260630.xsd#NetIncomeLossPerShare" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/SegmentReporting" xlink:href="solarmax-20260630.xsd#SegmentReporting" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/SubsequentEvents" xlink:href="solarmax-20260630.xsd#SubsequentEvents" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:href="solarmax-20260630.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesTables" xlink:href="solarmax-20260630.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/DisaggregationOfRevenueTables" xlink:href="solarmax-20260630.xsd#DisaggregationOfRevenueTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CashCashEquivalentsAndRestrictedCashTables" xlink:href="solarmax-20260630.xsd#CashCashEquivalentsAndRestrictedCashTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccountsReceivableNetTables" xlink:href="solarmax-20260630.xsd#AccountsReceivableNetTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CustomerLoansReceivableTables" xlink:href="solarmax-20260630.xsd#CustomerLoansReceivableTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InventoriesNetTables" xlink:href="solarmax-20260630.xsd#InventoriesNetTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNetTables" xlink:href="solarmax-20260630.xsd#OtherReceivablesAndCurrentAssetsNetTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/PropertyAndEquipmentTables" xlink:href="solarmax-20260630.xsd#PropertyAndEquipmentTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesTables" xlink:href="solarmax-20260630.xsd#InvestmentsInUnconsolidatedCompaniesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/FinancingArrangementsTables" xlink:href="solarmax-20260630.xsd#FinancingArrangementsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccruedExpensesAndOtherPayablesTables" xlink:href="solarmax-20260630.xsd#AccruedExpensesAndOtherPayablesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingenciesTables" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingenciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/StockholdersEquityDeficitTables" xlink:href="solarmax-20260630.xsd#StockholdersEquityDeficitTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/IncomeTaxesTables" xlink:href="solarmax-20260630.xsd#IncomeTaxesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/NetIncomeLossPerShareTables" xlink:href="solarmax-20260630.xsd#NetIncomeLossPerShareTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/SegmentReportingTables" xlink:href="solarmax-20260630.xsd#SegmentReportingTables" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/DescriptionOfBusinessDetailsNarrative" xlink:href="solarmax-20260630.xsd#DescriptionOfBusinessDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails" xlink:href="solarmax-20260630.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails1" xlink:href="solarmax-20260630.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails2" xlink:href="solarmax-20260630.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:href="solarmax-20260630.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/DisaggregationOfRevenueDetails" xlink:href="solarmax-20260630.xsd#DisaggregationOfRevenueDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CashCashEquivalentsAndRestrictedCashDetails" xlink:href="solarmax-20260630.xsd#CashCashEquivalentsAndRestrictedCashDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccountsReceivableNetDetails" xlink:href="solarmax-20260630.xsd#AccountsReceivableNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccountsReceivableNetDetailsNarrative" xlink:href="solarmax-20260630.xsd#AccountsReceivableNetDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/HeldToMaturityDebtInvestmentsDetailsNarrative" xlink:href="solarmax-20260630.xsd#HeldToMaturityDebtInvestmentsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/ReceivableFromSpicNetDetailsNarrative" xlink:href="solarmax-20260630.xsd#ReceivableFromSpicNetDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/LargeScaleEpcContractsDetailsNarrative" xlink:href="solarmax-20260630.xsd#LargeScaleEpcContractsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CustomerLoansReceivableDetails" xlink:href="solarmax-20260630.xsd#CustomerLoansReceivableDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CustomerLoansReceivableDetails1" xlink:href="solarmax-20260630.xsd#CustomerLoansReceivableDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CustomerLoansReceivableDetails2" xlink:href="solarmax-20260630.xsd#CustomerLoansReceivableDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CustomerLoansReceivableDetails3" xlink:href="solarmax-20260630.xsd#CustomerLoansReceivableDetails3" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CustomerLoansReceivableDetailsNarrative" xlink:href="solarmax-20260630.xsd#CustomerLoansReceivableDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InventoriesNetDetails" xlink:href="solarmax-20260630.xsd#InventoriesNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InventoriesNetDetails1" xlink:href="solarmax-20260630.xsd#InventoriesNetDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNetDetails" xlink:href="solarmax-20260630.xsd#OtherReceivablesAndCurrentAssetsNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNetDetailsNarrative" xlink:href="solarmax-20260630.xsd#OtherReceivablesAndCurrentAssetsNetDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/PropertyAndEquipmentNetDetails" xlink:href="solarmax-20260630.xsd#PropertyAndEquipmentNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/PropertyAndEquipmentNetDetailsNarrative" xlink:href="solarmax-20260630.xsd#PropertyAndEquipmentNetDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails" xlink:href="solarmax-20260630.xsd#InvestmentsInUnconsolidatedCompaniesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails1" xlink:href="solarmax-20260630.xsd#InvestmentsInUnconsolidatedCompaniesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails2" xlink:href="solarmax-20260630.xsd#InvestmentsInUnconsolidatedCompaniesDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails3" xlink:href="solarmax-20260630.xsd#InvestmentsInUnconsolidatedCompaniesDetails3" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetailsNarrative" xlink:href="solarmax-20260630.xsd#InvestmentsInUnconsolidatedCompaniesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/FinancingArrangementsDetails" xlink:href="solarmax-20260630.xsd#FinancingArrangementsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/FinancingArrangementsDetails1" xlink:href="solarmax-20260630.xsd#FinancingArrangementsDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/FinancingArrangementsDetails2" xlink:href="solarmax-20260630.xsd#FinancingArrangementsDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/FinancingArrangementsDetailsNarrative" xlink:href="solarmax-20260630.xsd#FinancingArrangementsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccruedExpensesAndOtherPayablesDetails" xlink:href="solarmax-20260630.xsd#AccruedExpensesAndOtherPayablesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccruedExpensesAndOtherPayablesDetails1" xlink:href="solarmax-20260630.xsd#AccruedExpensesAndOtherPayablesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AccruedExpensesAndOtherPayablesDetailsNarrative" xlink:href="solarmax-20260630.xsd#AccruedExpensesAndOtherPayablesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/ConcentrationsDetailsNarrative" xlink:href="solarmax-20260630.xsd#ConcentrationsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/AcquisitionContingenciesAndOtherPayableToUononeGroupDetailsNarrative" xlink:href="solarmax-20260630.xsd#AcquisitionContingenciesAndOtherPayableToUononeGroupDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingenciesDetails" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingenciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingenciesDetails1" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingenciesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingenciesDetails2" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingenciesDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingenciesDetails3" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingenciesDetails3" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingenciesDetails4" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingenciesDetails4" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:href="solarmax-20260630.xsd#CommitmentsAndContingenciesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/StockholdersEquityDeficitDetails" xlink:href="solarmax-20260630.xsd#StockholdersEquityDeficitDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/StockholdersEquityDeficitDetailsNarrative" xlink:href="solarmax-20260630.xsd#StockholdersEquityDeficitDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/IncomeTaxesDetails" xlink:href="solarmax-20260630.xsd#IncomeTaxesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/IncomeTaxesDetailsNarrative" xlink:href="solarmax-20260630.xsd#IncomeTaxesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/NetIncomeLossPerShareDetails" xlink:href="solarmax-20260630.xsd#NetIncomeLossPerShareDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/NetIncomeLossPerShareDetailsNarrative" xlink:href="solarmax-20260630.xsd#NetIncomeLossPerShareDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/SegmentReportingDetails" xlink:href="solarmax-20260630.xsd#SegmentReportingDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://solarmax.com/role/SubsequentEventsDetailsNarrative" xlink:href="solarmax-20260630.xsd#SubsequentEventsDetailsNarrative" xlink:type="simple" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" arcroleURI="http://xbrl.org/int/dim/arcrole/all" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#notAll" arcroleURI="http://xbrl.org/int/dim/arcrole/notAll" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/Cover" xlink:title="00000001 - Document - Cover Page Information">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CoverAbstract" xlink:label="loc_deiCover" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CondensedConsolidatedBalanceSheets" xlink:title="110200 - Statement - Condensed Consolidated Balance Sheets" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:title="110201 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfOperations" xlink:title="124100 - Statement - Unaudited Condensed Consolidated Statements of Operations" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:title="124101 - Statement - Unaudited Condensed Consolidated Statements of Comprehensive Income (Loss)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfChangesInStockholdersDeficit" xlink:title="148600 - Statement - Unaudited Condensed Consolidated Statements of Changes in Stockholders Deficit">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaapStatementEquityComponentsAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementEquityComponentsAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaapPreferredStockMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapPreferredStockMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaapCommonStockMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapCommonStockMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonMember" xlink:label="loc_us-gaapTreasuryStockCommonMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapTreasuryStockCommonMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaapAdditionalPaidInCapitalMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAdditionalPaidInCapitalMember" order="1024" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaapRetainedEarningsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapRetainedEarningsMember" order="1025" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember" order="1026" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaapSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharesIssued" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquity" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueNewIssues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueNewIssues" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ReverseSplitRoundingShares" xlink:label="loc_solarmaxReverseSplitRoundingShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxReverseSplitRoundingShares" order="7" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ReverseSplitRoundingAmount" xlink:label="loc_solarmaxReverseSplitRoundingAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxReverseSplitRoundingAmount" order="8" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/UnauditedCondensedConsolidatedStatementsOfCashFlows" xlink:title="170000 - Statement - Unaudited Condensed Consolidated Statements of Cash Flows" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/DescriptionOfBusiness" xlink:title="995446 - Disclosure - Description of Business" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPolicies" xlink:title="995447 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/DisaggregationOfRevenue" xlink:title="995448 - Disclosure - Disaggregation of Revenue" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CashCashEquivalentsAndRestrictedCash" xlink:title="995449 - Disclosure - Cash Cash Equivalents and Restricted Cash" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccountsReceivableNet" xlink:title="995450 - Disclosure - Accounts Receivable Net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/HeldToMaturityDebtInvestments" xlink:title="995451 - Disclosure - Held to Maturity Debt Investments" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/ReceivableFromSpicNet" xlink:title="995452 - Disclosure - Receivable from SPIC, Net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/LargeScaleEpcContracts" xlink:title="995453 - Disclosure - Large-scale EPC Contracts" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CustomerLoansReceivable" xlink:title="995454 - Disclosure - Customer Loans Receivable" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InventoriesNet" xlink:title="995455 - Disclosure - Inventories Net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNet" xlink:title="995456 - Disclosure - Other Receivables and Current Assets Net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/PropertyAndEquipmentNet" xlink:title="995457 - Disclosure - Property and Equipment, Net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InvestmentsInUnconsolidatedCompanies" xlink:title="995458 - Disclosure - Investments in Unconsolidated Companies" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/FinancingArrangements" xlink:title="995459 - Disclosure - Financing Arrangements" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccruedExpensesAndOtherPayables" xlink:title="995460 - Disclosure - Accrued Expenses and Other Payables" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/Concentrations" xlink:title="995461 - Disclosure - Concentrations" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AcquisitionContingenciesAndOtherPayableToUononeGroup" xlink:title="995462 - Disclosure - Acquisition Contingencies and Other Payable to Uonone Group" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/RelatedPartyTransactions" xlink:title="995463 - Disclosure - Related Party Transactions" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingencies" xlink:title="995464 - Disclosure - Commitments and Contingencies" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/StockholdersEquityDeficit" xlink:title="995465 - Disclosure - Stockholders Equity (Deficit)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/IncomeTaxes" xlink:title="995466 - Disclosure - Income Taxes" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/NetIncomeLossPerShare" xlink:title="995467 - Disclosure - Net Income (Loss) Per Share" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/SegmentReporting" xlink:title="995468 - Disclosure - Segment Reporting" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/SubsequentEvents" xlink:title="995469 - Disclosure - Subsequent Events" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:title="995470 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Policies)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesTables" xlink:title="995471 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/DisaggregationOfRevenueTables" xlink:title="995472 - Disclosure - Disaggregation of Revenue (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CashCashEquivalentsAndRestrictedCashTables" xlink:title="995473 - Disclosure - Cash Cash Equivalents and Restricted Cash (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccountsReceivableNetTables" xlink:title="995474 - Disclosure - Accounts Receivable Net (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CustomerLoansReceivableTables" xlink:title="995475 - Disclosure - Customer Loans Receivable (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InventoriesNetTables" xlink:title="995476 - Disclosure - Inventories Net (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNetTables" xlink:title="995477 - Disclosure - Other Receivables and Current Assets Net (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/PropertyAndEquipmentTables" xlink:title="995478 - Disclosure - Property and Equipment (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesTables" xlink:title="995479 - Disclosure - Investments in Unconsolidated Companies (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/FinancingArrangementsTables" xlink:title="995480 - Disclosure - Financing Arrangements (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccruedExpensesAndOtherPayablesTables" xlink:title="995481 - Disclosure - Accrued Expenses and Other Payables (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingenciesTables" xlink:title="995482 - Disclosure - Commitments and Contingencies (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/StockholdersEquityDeficitTables" xlink:title="995483 - Disclosure - Stockholders Equity (Deficit) (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/IncomeTaxesTables" xlink:title="995484 - Disclosure - Income Taxes (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/NetIncomeLossPerShareTables" xlink:title="995485 - Disclosure - Net Income (Loss) Per Share (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/SegmentReportingTables" xlink:title="995486 - Disclosure - Segment Reporting (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/DescriptionOfBusinessDetailsNarrative" xlink:title="995487 - Disclosure - Description of Business (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_TopMember" xlink:label="loc_solarmaxTopMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxTopMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityReverseStockSplit" xlink:label="loc_us-gaapStockholdersEquityReverseStockSplit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquityReverseStockSplit" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaapCommonStockParOrStatedValuePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockParOrStatedValuePerShare" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CommonStockNumberOfSharesAuthorizedOtherDisclosuresDescription" xlink:label="loc_solarmaxCommonStockNumberOfSharesAuthorizedOtherDisclosuresDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxCommonStockNumberOfSharesAuthorizedOtherDisclosuresDescription" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DetailsOfCommonStockNumberOfSharesOfOutstandingOtherDisclosuresDescription" xlink:label="loc_solarmaxDetailsOfCommonStockNumberOfSharesOfOutstandingOtherDisclosuresDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDetailsOfCommonStockNumberOfSharesOfOutstandingOtherDisclosuresDescription" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_StockIssuedDuringPeriodShareReverseStockSplits" xlink:label="loc_solarmaxStockIssuedDuringPeriodShareReverseStockSplits" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxStockIssuedDuringPeriodShareReverseStockSplits" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketableSecuritiesCurrent" xlink:label="loc_us-gaapMarketableSecuritiesCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapMarketableSecuritiesCurrent" order="6" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails" xlink:title="995488 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialSupportToNonconsolidatedLegalEntityAxis" xlink:label="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialSupportToNonconsolidatedLegalEntityDomain" xlink:label="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityAxis" xlink:to="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialSupportToNonconsolidatedLegalEntityDomain" xlink:label="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityAxis" xlink:to="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ACHTransactionsAndBusinessCreditCardsMember" xlink:label="loc_solarmaxACHTransactionsAndBusinessCreditCardsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFinancialSupportToNonconsolidatedLegalEntityDomain" xlink:to="loc_solarmaxACHTransactionsAndBusinessCreditCardsMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Deposits" xlink:label="loc_us-gaapDeposits" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDeposits" order="1" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails1" xlink:title="995489 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralAxis" xlink:label="loc_us-gaapCollateralAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapCollateralAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralDomain" xlink:label="loc_us-gaapCollateralDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapCollateralAxis" xlink:to="loc_us-gaapCollateralDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralDomain" xlink:label="loc_us-gaapCollateralDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapCollateralAxis" xlink:to="loc_us-gaapCollateralDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" order="1070" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" order="1070" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" order="1080" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_10" order="1090" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AutomobilesMember" xlink:label="loc_us-gaapAutomobilesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapCollateralDomain" xlink:to="loc_us-gaapAutomobilesMember" order="1071" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BottomMember" xlink:label="loc_solarmaxBottomMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxBottomMember" order="1072" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_TopMember" xlink:label="loc_solarmaxTopMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxTopMember" order="1073" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="loc_us-gaapFurnitureAndFixturesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapFurnitureAndFixturesMember" order="1074" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelatedIntangibleAssetsMember" xlink:label="loc_us-gaapCustomerRelatedIntangibleAssetsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="loc_us-gaapCustomerRelatedIntangibleAssetsMember" order="1075" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PublicUtilitiesPropertyPlantAndEquipmentEquipmentUsefulLife" xlink:label="loc_us-gaapPublicUtilitiesPropertyPlantAndEquipmentEquipmentUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPublicUtilitiesPropertyPlantAndEquipmentEquipmentUsefulLife" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LeaseholdImprovements" xlink:label="loc_solarmaxLeaseholdImprovements" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLeaseholdImprovements" order="2" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails2" xlink:title="995490 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details 2)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" xlink:to="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFairValueByFairValueHierarchyLevelAxis" xlink:to="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaapFairValueInputsLevel1Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" xlink:to="loc_us-gaapFairValueInputsLevel1Member" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaapFairValueInputsLevel2Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" xlink:to="loc_us-gaapFairValueInputsLevel2Member" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaapFairValueInputsLevel3Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueMeasurementsFairValueHierarchyDomain" xlink:to="loc_us-gaapFairValueInputsLevel3Member" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:label="loc_us-gaapCashAndCashEquivalentsFairValueDisclosure" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCashAndCashEquivalentsFairValueDisclosure" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LoansReceivableFairValueDisclosure" xlink:label="loc_us-gaapLoansReceivableFairValueDisclosure" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLoansReceivableFairValueDisclosure" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityMethodInvestments" xlink:label="loc_us-gaapEquityMethodInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapEquityMethodInvestments" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SecuredLoansAndLeasesReceivableRelatedParties" xlink:label="loc_solarmaxSecuredLoansAndLeasesReceivableRelatedParties" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxSecuredLoansAndLeasesReceivableRelatedParties" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleDebtFairValueDisclosures" xlink:label="loc_us-gaapConvertibleDebtFairValueDisclosures" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapConvertibleDebtFairValueDisclosures" order="5" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:title="995491 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeAxis" xlink:label="loc_us-gaapShortTermDebtTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapShortTermDebtTypeAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapShortTermDebtTypeAxis" xlink:to="loc_us-gaapShortTermDebtTypeDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapShortTermDebtTypeAxis" xlink:to="loc_us-gaapShortTermDebtTypeDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1070" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardDateAxis" xlink:label="loc_us-gaapAwardDateAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapAwardDateAxis" order="1070" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain" order="1080" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain_10" order="1090" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_TopMember" xlink:label="loc_solarmaxTopMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxTopMember" order="1071" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SGIPMember" xlink:label="loc_solarmaxSGIPMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxSGIPMember" order="1072" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableMember" xlink:label="loc_us-gaapConvertibleNotesPayableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtTypeDomain" xlink:to="loc_us-gaapConvertibleNotesPayableMember" order="1073" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SelfGenerationIncentiveProgramMember" xlink:label="loc_solarmaxSelfGenerationIncentiveProgramMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxSelfGenerationIncentiveProgramMember" order="1074" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AugustAndSeptemberTwoThousandTwentySixMember" xlink:label="loc_solarmaxAugustAndSeptemberTwoThousandTwentySixMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAwardDateDomain" xlink:to="loc_solarmaxAugustAndSeptemberTwoThousandTwentySixMember" order="1075" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BottomMember" xlink:label="loc_solarmaxBottomMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxBottomMember" order="1076" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xlink:label="loc_us-gaapForeignCurrencyTransactionGainLossBeforeTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapForeignCurrencyTransactionGainLossBeforeTax" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleSubordinatedDebtCurrent" xlink:label="loc_us-gaapConvertibleSubordinatedDebtCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapConvertibleSubordinatedDebtCurrent" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ConvertibleNotesBidPricePerShare" xlink:label="loc_solarmaxConvertibleNotesBidPricePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxConvertibleNotesBidPricePerShare" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashEquivalentsAtCarryingValue" xlink:label="loc_us-gaapCashEquivalentsAtCarryingValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCashEquivalentsAtCarryingValue" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_StockholdersEquityAmount" xlink:label="loc_solarmaxStockholdersEquityAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxStockholdersEquityAmount" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaapProceedsFromIssuanceOfCommonStock" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProceedsFromIssuanceOfCommonStock" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RetainedEarningsAccumulatedDeficitAmount" xlink:label="loc_solarmaxRetainedEarningsAccumulatedDeficitAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxRetainedEarningsAccumulatedDeficitAmount" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtCurrent" xlink:label="loc_us-gaapDebtCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtCurrent" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaapDebtInstrumentInterestRateStatedPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateStatedPercentage" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLoansPayableLongTerm" xlink:label="loc_us-gaapOtherLoansPayableLongTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLoansPayableLongTerm" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit" xlink:label="loc_us-gaapTimeDepositsAtOrAboveFDICInsuranceLimit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapTimeDepositsAtOrAboveFDICInsuranceLimit" order="11" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccountsReceivableRelatedParty" xlink:label="loc_solarmaxAccountsReceivableRelatedParty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxAccountsReceivableRelatedParty" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableNetCurrent" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperations" xlink:label="loc_us-gaapIncomeLossFromContinuingOperations" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncomeLossFromContinuingOperations" order="14" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_StockholdersEquityReverseStockSplits" xlink:label="loc_solarmaxStockholdersEquityReverseStockSplits" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxStockholdersEquityReverseStockSplits" order="15" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccountsReceivableCurrent" xlink:label="loc_solarmaxAccountsReceivableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxAccountsReceivableCurrent" order="16" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CooperativeInitiativeAmount" xlink:label="loc_solarmaxCooperativeInitiativeAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxCooperativeInitiativeAmount" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketingAndAdvertisingExpense" xlink:label="loc_us-gaapMarketingAndAdvertisingExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapMarketingAndAdvertisingExpense" order="18" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermPurchaseCommitmentPeriod" xlink:label="loc_us-gaapLongtermPurchaseCommitmentPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongtermPurchaseCommitmentPeriod" order="19" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SolarEnergyAndBatteryStorageSystemsAndComponentsSalesDescription" xlink:label="loc_solarmaxSolarEnergyAndBatteryStorageSystemsAndComponentsSalesDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxSolarEnergyAndBatteryStorageSystemsAndComponentsSalesDescription" order="20" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DebtInstrumentInterestRate" xlink:label="loc_solarmaxDebtInstrumentInterestRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDebtInstrumentInterestRate" order="21" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionConvertedInstrumentRate" xlink:label="loc_us-gaapDebtConversionConvertedInstrumentRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtConversionConvertedInstrumentRate" order="22" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RevenuePercentage" xlink:label="loc_solarmaxRevenuePercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxRevenuePercentage" order="23" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities" xlink:label="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities" order="24" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_PeriodOfProductionGuaranty" xlink:label="loc_solarmaxPeriodOfProductionGuaranty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxPeriodOfProductionGuaranty" order="25" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_PercentageOfWarrantCoverage" xlink:label="loc_solarmaxPercentageOfWarrantCoverage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxPercentageOfWarrantCoverage" order="26" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ProduceAtLeastOutputPercentage" xlink:label="loc_solarmaxProduceAtLeastOutputPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxProduceAtLeastOutputPercentage" order="27" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ProductionGuarantyDescription" xlink:label="loc_solarmaxProductionGuarantyDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxProductionGuarantyDescription" order="28" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionOriginalDebtInterestRateOfDebt" xlink:label="loc_us-gaapDebtConversionOriginalDebtInterestRateOfDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtConversionOriginalDebtInterestRateOfDebt" order="29" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleDebt" xlink:label="loc_us-gaapConvertibleDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapConvertibleDebt" order="30" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MalpracticeInsuranceCoverageFloor" xlink:label="loc_us-gaapMalpracticeInsuranceCoverageFloor" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapMalpracticeInsuranceCoverageFloor" order="31" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AmountOfWorkingCapitalDeficit" xlink:label="loc_solarmaxAmountOfWorkingCapitalDeficit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxAmountOfWorkingCapitalDeficit" order="32" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/DisaggregationOfRevenueDetails" xlink:title="995492 - Disclosure - Disaggregation of Revenue (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CashCashEquivalentsAndRestrictedCashDetails" xlink:title="995493 - Disclosure - Cash, Cash Equivalents and Restricted Cash (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicDistributionAxis" xlink:label="loc_us-gaapGeographicDistributionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapGeographicDistributionAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicDistributionDomain" xlink:label="loc_us-gaapGeographicDistributionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapGeographicDistributionAxis" xlink:to="loc_us-gaapGeographicDistributionDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicDistributionDomain" xlink:label="loc_us-gaapGeographicDistributionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapGeographicDistributionAxis" xlink:to="loc_us-gaapGeographicDistributionDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_UsCountryMember" xlink:label="loc_solarmaxUsCountryMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapGeographicDistributionDomain" xlink:to="loc_solarmaxUsCountryMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CNMember" xlink:label="loc_solarmaxCNMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapGeographicDistributionDomain" xlink:to="loc_solarmaxCNMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFDICInsuredAmount" xlink:label="loc_us-gaapCashFDICInsuredAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCashFDICInsuredAmount" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashUninsuredAmount" xlink:label="loc_us-gaapCashUninsuredAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCashUninsuredAmount" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashEquivalents" xlink:label="loc_us-gaapRestrictedCashEquivalents" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRestrictedCashEquivalents" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashAndCashEquivalents" xlink:label="loc_us-gaapRestrictedCashAndCashEquivalents" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRestrictedCashAndCashEquivalents" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LesscashAndCashEquivalents" xlink:label="loc_solarmaxLesscashAndCashEquivalents" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLesscashAndCashEquivalents" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCash" xlink:label="loc_us-gaapRestrictedCash" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRestrictedCash" order="6" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccountsReceivableNetDetails" xlink:title="995494 - Disclosure - Accounts Receivable, Net (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccountsReceivableNetDetailsNarrative" xlink:title="995495 - Disclosure - Accounts Receivable, Net (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SGIPMember" xlink:label="loc_solarmaxSGIPMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxSGIPMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LongfellowMember" xlink:label="loc_solarmaxLongfellowMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxLongfellowMember" order="1012" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableAllowanceForCreditLossExcludingAccruedInterestNoncurrent" xlink:label="loc_us-gaapAccountsReceivableAllowanceForCreditLossExcludingAccruedInterestNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableAllowanceForCreditLossExcludingAccruedInterestNoncurrent" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccountsReceivableRelatedParty" xlink:label="loc_solarmaxAccountsReceivableRelatedParty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxAccountsReceivableRelatedParty" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableNetCurrent" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/HeldToMaturityDebtInvestmentsDetailsNarrative" xlink:title="995496 - Disclosure - Held to Maturity Debt Investments (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicDistributionAxis" xlink:label="loc_us-gaapGeographicDistributionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapGeographicDistributionAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicDistributionDomain" xlink:label="loc_us-gaapGeographicDistributionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapGeographicDistributionAxis" xlink:to="loc_us-gaapGeographicDistributionDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicDistributionDomain" xlink:label="loc_us-gaapGeographicDistributionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapGeographicDistributionAxis" xlink:to="loc_us-gaapGeographicDistributionDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CNMember" xlink:label="loc_solarmaxCNMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapGeographicDistributionDomain" xlink:to="loc_solarmaxCNMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermInvestments" xlink:label="loc_us-gaapShortTermInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapShortTermInvestments" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInNotesPayableCurrent" xlink:label="loc_us-gaapIncreaseDecreaseInNotesPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncreaseDecreaseInNotesPayableCurrent" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentMaturityDateDescription" xlink:label="loc_us-gaapDebtInstrumentMaturityDateDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentMaturityDateDescription" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DescriptionForPromissoryNoteDue" xlink:label="loc_solarmaxDescriptionForPromissoryNoteDue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDescriptionForPromissoryNoteDue" order="4" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/ReceivableFromSpicNetDetailsNarrative" xlink:title="995497 - Disclosure - Receivable from SPIC, Net (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/LargeScaleEpcContractsDetailsNarrative" xlink:title="995498 - Disclosure - Large-scale EPC Contracts (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LongfellowBESSLLCMember" xlink:label="loc_solarmaxLongfellowBESSLLCMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxLongfellowBESSLLCMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_NaguaboMember" xlink:label="loc_solarmaxNaguaboMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxNaguaboMember" order="1012" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_YabucoaMember" xlink:label="loc_solarmaxYabucoaMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxYabucoaMember" order="1013" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_NavbootMember" xlink:label="loc_solarmaxNavbootMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxNavbootMember" order="1014" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractualObligation" xlink:label="loc_us-gaapContractualObligation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapContractualObligation" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommodityContractAssetNoncurrent" xlink:label="loc_us-gaapCommodityContractAssetNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommodityContractAssetNoncurrent" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerIncludingAssessedTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRevenueFromContractWithCustomerIncludingAssessedTax" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNet" xlink:label="loc_us-gaapAccountsReceivableNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableNet" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepositContractsAssets" xlink:label="loc_us-gaapDepositContractsAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDepositContractsAssets" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AmountOfFinancingComponentRevenues" xlink:label="loc_solarmaxAmountOfFinancingComponentRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxAmountOfFinancingComponentRevenues" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EquityMethodInvestmentOwnMembershipPercentage" xlink:label="loc_solarmaxEquityMethodInvestmentOwnMembershipPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxEquityMethodInvestmentOwnMembershipPercentage" order="7" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_StockholdersOwnershipPercentage" xlink:label="loc_solarmaxStockholdersOwnershipPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxStockholdersOwnershipPercentage" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaapCostOfRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCostOfRevenue" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCostOfOperatingRevenue" xlink:label="loc_us-gaapOtherCostOfOperatingRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherCostOfOperatingRevenue" order="10" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RelatedPartyTransactionAmountsOfTransactionRevenue" xlink:label="loc_solarmaxRelatedPartyTransactionAmountsOfTransactionRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxRelatedPartyTransactionAmountsOfTransactionRevenue" order="11" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RevenuesExpectedToGenerateFromContract" xlink:label="loc_solarmaxRevenuesExpectedToGenerateFromContract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxRevenuesExpectedToGenerateFromContract" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherInventory" xlink:label="loc_us-gaapOtherInventory" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherInventory" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryForLongTermContractsOrPrograms" xlink:label="loc_us-gaapInventoryForLongTermContractsOrPrograms" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInventoryForLongTermContractsOrPrograms" order="14" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BilledContractPriceReceivables" xlink:label="loc_solarmaxBilledContractPriceReceivables" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxBilledContractPriceReceivables" order="15" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DescriptionOfContractOfConsideration" xlink:label="loc_solarmaxDescriptionOfContractOfConsideration" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDescriptionOfContractOfConsideration" order="16" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CustomerLoansReceivableDetails" xlink:title="995499 - Disclosure - Customer Loans Receivable (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaapFinancialInstrumentAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFinancialInstrumentAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InternalCreditAssessmentAxis" xlink:label="loc_us-gaapInternalCreditAssessmentAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapInternalCreditAssessmentAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InternalCreditAssessmentDomain" xlink:label="loc_us-gaapInternalCreditAssessmentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapInternalCreditAssessmentAxis" xlink:to="loc_us-gaapInternalCreditAssessmentDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InternalCreditAssessmentDomain" xlink:label="loc_us-gaapInternalCreditAssessmentDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapInternalCreditAssessmentAxis" xlink:to="loc_us-gaapInternalCreditAssessmentDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_YearOfOriginationTwoZeoTwoThreeMember" xlink:label="loc_solarmaxYearOfOriginationTwoZeoTwoThreeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxYearOfOriginationTwoZeoTwoThreeMember" order="1041" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrimeMember" xlink:label="loc_us-gaapPrimeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapInternalCreditAssessmentDomain" xlink:to="loc_us-gaapPrimeMember" order="1042" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_NearPrimeMember" xlink:label="loc_solarmaxNearPrimeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapInternalCreditAssessmentDomain" xlink:to="loc_solarmaxNearPrimeMember" order="1043" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SubPrimeMember" xlink:label="loc_solarmaxSubPrimeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapInternalCreditAssessmentDomain" xlink:to="loc_solarmaxSubPrimeMember" order="1044" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BusinessEntityMember" xlink:label="loc_solarmaxBusinessEntityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapInternalCreditAssessmentDomain" xlink:to="loc_solarmaxBusinessEntityMember" order="1045" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_YearOfOriginationTwoZeoTwoTwoMember" xlink:label="loc_solarmaxYearOfOriginationTwoZeoTwoTwoMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxYearOfOriginationTwoZeoTwoTwoMember" order="1046" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_YearOfOriginationTwoZeoTwoOneMember" xlink:label="loc_solarmaxYearOfOriginationTwoZeoTwoOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxYearOfOriginationTwoZeoTwoOneMember" order="1047" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_YearOfOriginationPriorMember" xlink:label="loc_solarmaxYearOfOriginationPriorMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxYearOfOriginationPriorMember" order="1048" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_YearOfOriginationMember" xlink:label="loc_solarmaxYearOfOriginationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxYearOfOriginationMember" order="1049" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesPercent" xlink:label="loc_us-gaapFinancingReceivableModificationToTotalFinancingReceivablesPercent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapFinancingReceivableModificationToTotalFinancingReceivablesPercent" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_FicoScoreSixeightzeroAndGreater" xlink:label="loc_solarmaxFicoScoreSixeightzeroAndGreater" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxFicoScoreSixeightzeroAndGreater" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_NearprimeficoScoresixtwentytosixsevennine" xlink:label="loc_solarmaxNearprimeficoScoresixtwentytosixsevennine" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxNearprimeficoScoresixtwentytosixsevennine" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SubprimeficoscoreLessThansixtwenty" xlink:label="loc_solarmaxSubprimeficoscoreLessThansixtwenty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxSubprimeficoscoreLessThansixtwenty" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BusinessentityficoNotAvailable" xlink:label="loc_solarmaxBusinessentityficoNotAvailable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxBusinessentityficoNotAvailable" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReceivablesFromCustomers" xlink:label="loc_us-gaapReceivablesFromCustomers" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapReceivablesFromCustomers" order="6" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CustomerLoansReceivableDetails1" xlink:title="995500 - Disclosure - Customer Loans Receivable (Details 1)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CustomerLoansReceivableDetails2" xlink:title="995501 - Disclosure - Customer Loans Receivable (Details 2)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CustomerLoansReceivableDetails3" xlink:title="995502 - Disclosure - Customer Loans Receivable (Details 3)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CustomerLoansReceivableDetailsNarrative" xlink:title="995503 - Disclosure - Customer Loans Receivable (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_TopMember" xlink:label="loc_solarmaxTopMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxTopMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BottomMember" xlink:label="loc_solarmaxBottomMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxBottomMember" order="1012" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="loc_us-gaapDebtInstrumentInterestRateEffectivePercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateEffectivePercentage" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRefundableFeesRevenueRecognized1" xlink:label="loc_us-gaapCustomerRefundableFeesRevenueRecognized1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCustomerRefundableFeesRevenueRecognized1" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateDuringPeriod" xlink:label="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LoanPortfolioPercentage" xlink:label="loc_solarmaxLoanPortfolioPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLoanPortfolioPercentage" order="4" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InventoriesNetDetails" xlink:title="995504 - Disclosure - Inventories, Net (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InventoriesNetDetails1" xlink:title="995505 - Disclosure - Inventories, Net (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis" xlink:label="loc_us-gaapLongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapLongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermPurchaseCommitmentCategoryOfItemPurchasedDomain" xlink:label="loc_us-gaapLongTermPurchaseCommitmentCategoryOfItemPurchasedDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapLongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis" xlink:to="loc_us-gaapLongTermPurchaseCommitmentCategoryOfItemPurchasedDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermPurchaseCommitmentCategoryOfItemPurchasedDomain" xlink:label="loc_us-gaapLongTermPurchaseCommitmentCategoryOfItemPurchasedDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapLongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis" xlink:to="loc_us-gaapLongTermPurchaseCommitmentCategoryOfItemPurchasedDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LEDLightsMember" xlink:label="loc_solarmaxLEDLightsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLongTermPurchaseCommitmentCategoryOfItemPurchasedDomain" xlink:to="loc_solarmaxLEDLightsMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ComponentsMember" xlink:label="loc_solarmaxComponentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLongTermPurchaseCommitmentCategoryOfItemPurchasedDomain" xlink:to="loc_solarmaxComponentsMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryGross" xlink:label="loc_us-gaapInventoryGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInventoryGross" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryValuationReserves" xlink:label="loc_us-gaapInventoryValuationReserves" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInventoryValuationReserves" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInventoryNet" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNetDetails" xlink:title="995506 - Disclosure - Other Receivables and Current Assets, Net (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/OtherReceivablesAndCurrentAssetsNetDetailsNarrative" xlink:title="995507 - Disclosure - Other Receivables and Current Assets, Net (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LongfellowProjectMember" xlink:label="loc_solarmaxLongfellowProjectMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxLongfellowProjectMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfDebt" xlink:label="loc_us-gaapRepaymentsOfDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRepaymentsOfDebt" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MaterialsSuppliesAndOther" xlink:label="loc_us-gaapMaterialsSuppliesAndOther" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapMaterialsSuppliesAndOther" order="2" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/PropertyAndEquipmentNetDetails" xlink:title="995508 - Disclosure - Property and Equipment, Net (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralAxis" xlink:label="loc_us-gaapCollateralAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapCollateralAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralDomain" xlink:label="loc_us-gaapCollateralDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapCollateralAxis" xlink:to="loc_us-gaapCollateralDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralDomain" xlink:label="loc_us-gaapCollateralDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapCollateralAxis" xlink:to="loc_us-gaapCollateralDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AutomobilesMember" xlink:label="loc_us-gaapAutomobilesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapCollateralDomain" xlink:to="loc_us-gaapAutomobilesMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="loc_us-gaapFurnitureAndFixturesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapFurnitureAndFixturesMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SolarSystemsLeasedToCustomersMember" xlink:label="loc_solarmaxSolarSystemsLeasedToCustomersMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_solarmaxSolarSystemsLeasedToCustomersMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="loc_us-gaapLeaseholdImprovementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapLeaseholdImprovementsMember" order="1024" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaapPropertyPlantAndEquipmentGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentGross" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/PropertyAndEquipmentNetDetailsNarrative" xlink:title="995509 - Disclosure - Property and Equipment, Net (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails" xlink:title="995510 - Disclosure - Investments in Unconsolidated Companies (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentTypeAxis" xlink:label="loc_us-gaapInvestmentTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapInvestmentTypeAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="loc_us-gaapInvestmentTypeCategorizationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapInvestmentTypeAxis" xlink:to="loc_us-gaapInvestmentTypeCategorizationMember" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="loc_us-gaapInvestmentTypeCategorizationMember_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapInvestmentTypeAxis" xlink:to="loc_us-gaapInvestmentTypeCategorizationMember_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_YilongTwoMember" xlink:label="loc_solarmaxYilongTwoMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapInvestmentTypeCategorizationMember" xlink:to="loc_solarmaxYilongTwoMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_XingrenMember" xlink:label="loc_solarmaxXingrenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapInvestmentTypeCategorizationMember" xlink:to="loc_solarmaxXingrenMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AnchaMember" xlink:label="loc_solarmaxAnchaMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapInvestmentTypeCategorizationMember" xlink:to="loc_solarmaxAnchaMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Investments" xlink:label="loc_us-gaapInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInvestments" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetInvestmentIncome" xlink:label="loc_us-gaapNetInvestmentIncome" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetInvestmentIncome" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EffectOfExchangeRate" xlink:label="loc_solarmaxEffectOfExchangeRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxEffectOfExchangeRate" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails1" xlink:title="995511 - Disclosure - Investments in Unconsolidated Companies (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaapFairValueByAssetClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFairValueByAssetClassAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFairValueByAssetClassAxis" xlink:to="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFairValueByAssetClassAxis" xlink:to="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EquityMethodNoncontrollingInvestmentsMember" xlink:label="loc_solarmaxEquityMethodNoncontrollingInvestmentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="loc_solarmaxEquityMethodNoncontrollingInvestmentsMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaapAssetsCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssetsCurrent" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_FinancialNoncurrentAssets" xlink:label="loc_solarmaxFinancialNoncurrentAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxFinancialNoncurrentAssets" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssets" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaapLiabilitiesCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesCurrent" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesNoncurrent" xlink:label="loc_us-gaapLiabilitiesNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesNoncurrent" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MembersCapital" xlink:label="loc_us-gaapMembersCapital" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapMembersCapital" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquity" order="7" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails2" xlink:title="995512 - Disclosure - Investments in Unconsolidated Companies (Details 2)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaapFairValueByAssetClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFairValueByAssetClassAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFairValueByAssetClassAxis" xlink:to="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFairValueByAssetClassAxis" xlink:to="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EquityMethodNoncontrollingInvestmentsMember" xlink:label="loc_solarmaxEquityMethodNoncontrollingInvestmentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="loc_solarmaxEquityMethodNoncontrollingInvestmentsMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRevenues" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaapGrossProfit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapGrossProfit" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetails3" xlink:title="995513 - Disclosure - Investments in Unconsolidated Companies (Details 3)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LongfellowMember" xlink:label="loc_solarmaxLongfellowMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxLongfellowMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNet" xlink:label="loc_us-gaapAccountsReceivableNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableNet" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNet" xlink:label="loc_us-gaapContractWithCustomerAssetNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapContractWithCustomerAssetNet" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNetOfAllowancesCustomerAdvancesAndProgressBillings" xlink:label="loc_us-gaapInventoryNetOfAllowancesCustomerAdvancesAndProgressBillings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInventoryNetOfAllowancesCustomerAdvancesAndProgressBillings" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssets" xlink:label="loc_us-gaapOtherAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherAssets" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_VariableInterestsEntityMaximumExposureToLoss" xlink:label="loc_solarmaxVariableInterestsEntityMaximumExposureToLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxVariableInterestsEntityMaximumExposureToLoss" order="5" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/InvestmentsInUnconsolidatedCompaniesDetailsNarrative" xlink:title="995514 - Disclosure - Investments in Unconsolidated Companies (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_PRCMember" xlink:label="loc_solarmaxPRCMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_solarmaxPRCMember" order="1041" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LongfellowBESSLLCMember" xlink:label="loc_solarmaxLongfellowBESSLLCMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxLongfellowBESSLLCMember" order="1042" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LLCAgreementMember" xlink:label="loc_solarmaxLLCAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxLLCAgreementMember" order="1043" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EPCContractMember" xlink:label="loc_solarmaxEPCContractMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxEPCContractMember" order="1044" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_VIEMember" xlink:label="loc_solarmaxVIEMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxVIEMember" order="1045" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EntitiesMember" xlink:label="loc_solarmaxEntitiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_solarmaxEntitiesMember" order="1046" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNet" xlink:label="loc_us-gaapAccountsReceivableNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableNet" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNet" xlink:label="loc_us-gaapContractWithCustomerAssetNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapContractWithCustomerAssetNet" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_VariableInterestsEntityMaximumExposureToLoss" xlink:label="loc_solarmaxVariableInterestsEntityMaximumExposureToLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxVariableInterestsEntityMaximumExposureToLoss" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_InvestmentOwnershipPercentage" xlink:label="loc_solarmaxInvestmentOwnershipPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxInvestmentOwnershipPercentage" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractualObligation" xlink:label="loc_us-gaapContractualObligation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapContractualObligation" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ContingentOnTaxEquityTransactionPaid" xlink:label="loc_solarmaxContingentOnTaxEquityTransactionPaid" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxContingentOnTaxEquityTransactionPaid" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ContractWithCustomerRemainingPerformanceObligation" xlink:label="loc_solarmaxContractWithCustomerRemainingPerformanceObligation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxContractWithCustomerRemainingPerformanceObligation" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNetOfAllowancesCustomerAdvancesAndProgressBillings" xlink:label="loc_us-gaapInventoryNetOfAllowancesCustomerAdvancesAndProgressBillings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInventoryNetOfAllowancesCustomerAdvancesAndProgressBillings" order="8" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_NonControllingInterestEquityMethodInvestmentOwnershipPercentage" xlink:label="loc_solarmaxNonControllingInterestEquityMethodInvestmentOwnershipPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxNonControllingInterestEquityMethodInvestmentOwnershipPercentage" order="9" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_MinorityInterestsOwnershipPercentageByParent" xlink:label="loc_solarmaxMinorityInterestsOwnershipPercentageByParent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxMinorityInterestsOwnershipPercentageByParent" order="10" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_InvestmentNotRecognizedDueToUnpaidContribution" xlink:label="loc_solarmaxInvestmentNotRecognizedDueToUnpaidContribution" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxInvestmentNotRecognizedDueToUnpaidContribution" order="11" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CapitalCommitmentUnfundedAmount" xlink:label="loc_solarmaxCapitalCommitmentUnfundedAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxCapitalCommitmentUnfundedAmount" order="12" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EquityInterestTransferredToTheCustomerEquityOwnershipPercentage" xlink:label="loc_solarmaxEquityInterestTransferredToTheCustomerEquityOwnershipPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxEquityInterestTransferredToTheCustomerEquityOwnershipPercentage" order="13" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/FinancingArrangementsDetails" xlink:title="995515 - Disclosure - Financing Arrangements (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaapFinancialInstrumentAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFinancialInstrumentAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleDebtSecuritiesMember" xlink:label="loc_us-gaapConvertibleDebtSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_us-gaapConvertibleDebtSecuritiesMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EBFiveMember" xlink:label="loc_solarmaxEBFiveMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_solarmaxEBFiveMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLongTermDebt" xlink:label="loc_us-gaapOtherLongTermDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLongTermDebt" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtIssuanceCostsLineOfCreditArrangementsGross" xlink:label="loc_us-gaapDebtIssuanceCostsLineOfCreditArrangementsGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtIssuanceCostsLineOfCreditArrangementsGross" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLongTermDebtCurrent" xlink:label="loc_us-gaapOtherLongTermDebtCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLongTermDebtCurrent" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLongTermDebtNoncurrent" xlink:label="loc_us-gaapOtherLongTermDebtNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLongTermDebtNoncurrent" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayable" xlink:label="loc_us-gaapConvertibleNotesPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapConvertibleNotesPayable" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LoansPayable" xlink:label="loc_us-gaapLoansPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLoansPayable" order="6" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/FinancingArrangementsDetails1" xlink:title="995516 - Disclosure - Financing Arrangements (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EBFiveMember" xlink:label="loc_solarmaxEBFiveMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_solarmaxEBFiveMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CleanEnergyFundingIILPMember" xlink:label="loc_solarmaxCleanEnergyFundingIILPMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxCleanEnergyFundingIILPMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CleanEnergyFundingLPMember" xlink:label="loc_solarmaxCleanEnergyFundingLPMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxCleanEnergyFundingLPMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LoansPayable" xlink:label="loc_us-gaapLoansPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLoansPayable" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LoansPayableCurrent" xlink:label="loc_us-gaapLoansPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLoansPayableCurrent" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermLoansPayable" xlink:label="loc_us-gaapLongTermLoansPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermLoansPayable" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/FinancingArrangementsDetails2" xlink:title="995517 - Disclosure - Financing Arrangements (Details 2)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EBFiveMember" xlink:label="loc_solarmaxEBFiveMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_solarmaxEBFiveMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_FinancialArrangementTotalMember" xlink:label="loc_solarmaxFinancialArrangementTotalMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxFinancialArrangementTotalMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CovertibleNotesMember" xlink:label="loc_solarmaxCovertibleNotesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxCovertibleNotesMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:label="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:label="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:label="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:label="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:label="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearsSix" xlink:label="loc_solarmaxLongTermDebtMaturitiesRepaymentsOfPrincipalInYearsSix" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLongTermDebtMaturitiesRepaymentsOfPrincipalInYearsSix" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaapLongTermDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermDebt" order="7" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/FinancingArrangementsDetailsNarrative" xlink:title="995518 - Disclosure - Financing Arrangements (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_TopMember" xlink:label="loc_solarmaxTopMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxTopMember" order="1031" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BottomMember" xlink:label="loc_solarmaxBottomMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxBottomMember" order="1032" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EBFiveMember" xlink:label="loc_solarmaxEBFiveMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_solarmaxEBFiveMember" order="1033" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CleanEnergyFundingIILPMember" xlink:label="loc_solarmaxCleanEnergyFundingIILPMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxCleanEnergyFundingIILPMember" order="1034" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CleanEnergyFundingLPMember" xlink:label="loc_solarmaxCleanEnergyFundingLPMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxCleanEnergyFundingLPMember" order="1035" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CovertibleNotesMember" xlink:label="loc_solarmaxCovertibleNotesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxCovertibleNotesMember" order="1036" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EventOfDefaultOnConvertibleNotesMember" xlink:label="loc_solarmaxEventOfDefaultOnConvertibleNotesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxEventOfDefaultOnConvertibleNotesMember" order="1037" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaapGainsLossesOnExtinguishmentOfDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapGainsLossesOnExtinguishmentOfDebt" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DebtConversionOriginalDebtAmount" xlink:label="loc_solarmaxDebtConversionOriginalDebtAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDebtConversionOriginalDebtAmount" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionConvertedInstrumentAmount1" xlink:label="loc_us-gaapDebtConversionConvertedInstrumentAmount1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtConversionConvertedInstrumentAmount1" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAnnualPrincipalPayment" xlink:label="loc_us-gaapDebtInstrumentAnnualPrincipalPayment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentAnnualPrincipalPayment" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ConvertibleDebtInstrumentInterestRate" xlink:label="loc_solarmaxConvertibleDebtInstrumentInterestRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxConvertibleDebtInstrumentInterestRate" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EventInterestOnDebtDescription" xlink:label="loc_solarmaxEventInterestOnDebtDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxEventInterestOnDebtDescription" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepositLiabilitiesAccruedInterest" xlink:label="loc_us-gaapDepositLiabilitiesAccruedInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDepositLiabilitiesAccruedInterest" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLoansPayable" xlink:label="loc_us-gaapOtherLoansPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLoansPayable" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaapDebtInstrumentInterestRateStatedPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateStatedPercentage" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockConvertibleConversionPrice" xlink:label="loc_us-gaapPreferredStockConvertibleConversionPrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPreferredStockConvertibleConversionPrice" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromLoans" xlink:label="loc_us-gaapProceedsFromLoans" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProceedsFromLoans" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaapInterestExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInterestExpense" order="12" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_InterestExpensesRelatedParty" xlink:label="loc_solarmaxInterestExpensesRelatedParty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxInterestExpensesRelatedParty" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentInterestRate" xlink:label="loc_us-gaapInvestmentInterestRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInvestmentInterestRate" order="14" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccruedExpensesAndOtherPayablesDetails" xlink:title="995519 - Disclosure - Accrued Expenses and Other Payables (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaapFinancialInstrumentAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFinancialInstrumentAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFinancialInstrumentAxis" xlink:to="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccruedWarrantyLiabilityMember" xlink:label="loc_solarmaxAccruedWarrantyLiabilityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxAccruedWarrantyLiabilityMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccruedChinaLegalJudgmentForFarmlAndOccupationTaxMember" xlink:label="loc_solarmaxAccruedChinaLegalJudgmentForFarmlAndOccupationTaxMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxAccruedChinaLegalJudgmentForFarmlAndOccupationTaxMember" order="1012" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CustomerDepositsMember" xlink:label="loc_solarmaxCustomerDepositsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxCustomerDepositsMember" order="1013" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccruedOperatingAndProjectPayablesMember" xlink:label="loc_solarmaxAccruedOperatingAndProjectPayablesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxAccruedOperatingAndProjectPayablesMember" order="1014" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_PayableToUononeMember" xlink:label="loc_solarmaxPayableToUononeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxPayableToUononeMember" order="1015" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccruedCompensationExpensesMember" xlink:label="loc_solarmaxAccruedCompensationExpensesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxAccruedCompensationExpensesMember" order="1016" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RetainagePayableToVendorsMember" xlink:label="loc_solarmaxRetainagePayableToVendorsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxRetainagePayableToVendorsMember" order="1017" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_PreacquisitionLiabilityMember" xlink:label="loc_solarmaxPreacquisitionLiabilityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxPreacquisitionLiabilityMember" order="1018" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_VATTaxesPayableMember" xlink:label="loc_solarmaxVATTaxesPayableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxVATTaxesPayableMember" order="1019" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_IncomeTaxesPayableMember" xlink:label="loc_solarmaxIncomeTaxesPayableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxIncomeTaxesPayableMember" order="1020" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RefundableVendorBidDepositsMember" xlink:label="loc_solarmaxRefundableVendorBidDepositsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapTransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="loc_solarmaxRefundableVendorBidDepositsMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAccountsPayableAndAccruedLiabilities" xlink:label="loc_us-gaapOtherAccountsPayableAndAccruedLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherAccountsPayableAndAccruedLiabilities" order="1" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccruedExpensesAndOtherPayablesDetails1" xlink:title="995520 - Disclosure - Accrued Expenses and Other Payables (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByLiabilityClassAxis" xlink:label="loc_us-gaapFairValueByLiabilityClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFairValueByLiabilityClassAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="loc_us-gaapFairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFairValueByLiabilityClassAxis" xlink:to="loc_us-gaapFairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="loc_us-gaapFairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFairValueByLiabilityClassAxis" xlink:to="loc_us-gaapFairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_WarrantyLiabilityMember" xlink:label="loc_solarmaxWarrantyLiabilityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:to="loc_solarmaxWarrantyLiabilityMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilities" xlink:label="loc_us-gaapOtherLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLiabilities" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ProvisionForWarrantyLiability" xlink:label="loc_solarmaxProvisionForWarrantyLiability" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxProvisionForWarrantyLiability" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ExpendituresAndAdjustments" xlink:label="loc_solarmaxExpendituresAndAdjustments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxExpendituresAndAdjustments" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EffectOfExchangeRate" xlink:label="loc_solarmaxEffectOfExchangeRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxEffectOfExchangeRate" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AccruedExpensesAndOtherPayablesCurrent" xlink:label="loc_solarmaxAccruedExpensesAndOtherPayablesCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxAccruedExpensesAndOtherPayablesCurrent" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_NonCurrentOtherLiabilities" xlink:label="loc_solarmaxNonCurrentOtherLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxNonCurrentOtherLiabilities" order="7" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AccruedExpensesAndOtherPayablesDetailsNarrative" xlink:title="995521 - Disclosure - Accrued Expenses and Other Payables (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ChiefExecutiveOfficerMember" xlink:label="loc_srtChiefExecutiveOfficerMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_srtChiefExecutiveOfficerMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeBenefitsAndShareBasedCompensation" xlink:label="loc_us-gaapEmployeeBenefitsAndShareBasedCompensation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapEmployeeBenefitsAndShareBasedCompensation" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PartnersCapitalAccountUnitBasedCompensation" xlink:label="loc_us-gaapPartnersCapitalAccountUnitBasedCompensation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPartnersCapitalAccountUnitBasedCompensation" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OccupationTaxesAccruedFarmlandOccupationTax" xlink:label="loc_solarmaxOccupationTaxesAccruedFarmlandOccupationTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxOccupationTaxesAccruedFarmlandOccupationTax" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/ConcentrationsDetailsNarrative" xlink:title="995522 - Disclosure - Concentrations (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MajorCustomersAxis" xlink:label="loc_srtMajorCustomersAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtMajorCustomersAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srtNameOfMajorCustomerDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtMajorCustomersAxis" xlink:to="loc_srtNameOfMajorCustomerDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srtNameOfMajorCustomerDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtMajorCustomersAxis" xlink:to="loc_srtNameOfMajorCustomerDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaapConcentrationRiskByBenchmarkAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapConcentrationRiskByBenchmarkAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OneMajorCustomersMember" xlink:label="loc_solarmaxOneMajorCustomersMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_solarmaxOneMajorCustomersMember" order="1041" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableMember" xlink:label="loc_us-gaapAccountsReceivableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_us-gaapAccountsReceivableMember" order="1042" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ContractAssetsMember" xlink:label="loc_solarmaxContractAssetsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_solarmaxContractAssetsMember" order="1043" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SupplierAMember" xlink:label="loc_solarmaxSupplierAMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_solarmaxSupplierAMember" order="1044" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SupplierBMember" xlink:label="loc_solarmaxSupplierBMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_solarmaxSupplierBMember" order="1045" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SupplierBOneMember" xlink:label="loc_solarmaxSupplierBOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_solarmaxSupplierBOneMember" order="1046" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SupplierAOneMember" xlink:label="loc_solarmaxSupplierAOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_solarmaxSupplierAOneMember" order="1047" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SupplierCMember" xlink:label="loc_solarmaxSupplierCMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_solarmaxSupplierCMember" order="1048" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_MajorCustomersMember" xlink:label="loc_solarmaxMajorCustomersMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_solarmaxMajorCustomersMember" order="1049" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsPayableCurrent" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RevenuesAndAccountsReceivablesDescription" xlink:label="loc_solarmaxRevenuesAndAccountsReceivablesDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxRevenuesAndAccountsReceivablesDescription" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForRepurchaseOfWarrants" xlink:label="loc_us-gaapPaymentsForRepurchaseOfWarrants" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPaymentsForRepurchaseOfWarrants" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_PaymentsForRepurchaseOfWarrant" xlink:label="loc_solarmaxPaymentsForRepurchaseOfWarrant" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxPaymentsForRepurchaseOfWarrant" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableInterestBearingInterestRate" xlink:label="loc_us-gaapAccountsPayableInterestBearingInterestRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsPayableInterestBearingInterestRate" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent" xlink:label="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ThirdPartyArrangementConcentrationRiskPercentage" xlink:label="loc_solarmaxThirdPartyArrangementConcentrationRiskPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxThirdPartyArrangementConcentrationRiskPercentage" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" xlink:label="loc_us-gaapConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" order="8" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/AcquisitionContingenciesAndOtherPayableToUononeGroupDetailsNarrative" xlink:title="995523 - Disclosure - Acquisition Contingencies and Other Payable to Uonone Group (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaapAwardTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapAwardTypeAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapAwardTypeAxis" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapAwardTypeAxis" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_MayTwelveTwoThousandSixteenMember" xlink:label="loc_solarmaxMayTwelveTwoThousandSixteenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_solarmaxMayTwelveTwoThousandSixteenMember" order="1031" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_UononeGroupMember" xlink:label="loc_solarmaxUononeGroupMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_solarmaxUononeGroupMember" order="1032" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentOfNotesReceivableFromRelatedParties" xlink:label="loc_us-gaapRepaymentOfNotesReceivableFromRelatedParties" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRepaymentOfNotesReceivableFromRelatedParties" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RelatedPartyTransactionsPayablesCurrent" xlink:label="loc_solarmaxRelatedPartyTransactionsPayablesCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxRelatedPartyTransactionsPayablesCurrent" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DescriptionOfPayment" xlink:label="loc_solarmaxDescriptionOfPayment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDescriptionOfPayment" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingenciesDetails" xlink:title="995524 - Disclosure - Commitments and Contingencies (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingenciesDetails1" xlink:title="995525 - Disclosure - Commitments and Contingencies (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OfficesWarehouseFacilitiesAndEquipmentMember" xlink:label="loc_solarmaxOfficesWarehouseFacilitiesAndEquipmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_solarmaxOfficesWarehouseFacilitiesAndEquipmentMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearTwo" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearTwo" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearThree" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearThree" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearFour" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearFour" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" xlink:label="loc_solarmaxLesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDue" order="7" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingenciesDetails2" xlink:title="995526 - Disclosure - Commitments and Contingencies (Details 2)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OperatingLeaseLiabilitiesMember" xlink:label="loc_solarmaxOperatingLeaseLiabilitiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxOperatingLeaseLiabilitiesMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearTwo" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearTwo" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearThree" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearThree" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearFour" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDueYearFour" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" xlink:label="loc_solarmaxLesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityPaymentsDue" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="loc_us-gaapLesseeOperatingLeaseLiabilityUndiscountedExcessAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLesseeOperatingLeaseLiabilityUndiscountedExcessAmount" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiability" xlink:label="loc_us-gaapOperatingLeaseLiability" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLeaseLiability" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLeaseLiabilityCurrent" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLeaseLiabilityNoncurrent" order="11" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingenciesDetails3" xlink:title="995527 - Disclosure - Commitments and Contingencies (Details 3)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingenciesDetails4" xlink:title="995528 - Disclosure - Commitments and Contingencies (Details 4)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:title="995529 - Disclosure - Commitments and Contingencies (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EmploymentAgreementsMember" xlink:label="loc_solarmaxEmploymentAgreementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="loc_solarmaxEmploymentAgreementsMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ChiefExecutiveOfficersMember" xlink:label="loc_solarmaxChiefExecutiveOfficersMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_solarmaxChiefExecutiveOfficersMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesPayments1" xlink:label="loc_us-gaapAccrualForEnvironmentalLossContingenciesPayments1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccrualForEnvironmentalLossContingenciesPayments1" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecurityDepositLiability" xlink:label="loc_us-gaapSecurityDepositLiability" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSecurityDepositLiability" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted" xlink:label="loc_us-gaapPurchaseCommitmentRemainingMinimumAmountCommitted" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPurchaseCommitmentRemainingMinimumAmountCommitted" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssets" xlink:label="loc_us-gaapPrepaidExpenseAndOtherAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPrepaidExpenseAndOtherAssets" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeasePayments" xlink:label="loc_us-gaapOperatingLeasePayments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLeasePayments" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_AnnualBaseRentDescription" xlink:label="loc_solarmaxAnnualBaseRentDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxAnnualBaseRentDescription" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OperatingLeaseDiscountRate" xlink:label="loc_solarmaxOperatingLeaseDiscountRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxOperatingLeaseDiscountRate" order="7" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OperatingLeasesRentExpensesNet" xlink:label="loc_solarmaxOperatingLeasesRentExpensesNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxOperatingLeasesRentExpensesNet" order="8" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OperatingLeaseTermOfContractDescription" xlink:label="loc_solarmaxOperatingLeaseTermOfContractDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxOperatingLeaseTermOfContractDescription" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalariesAndWages" xlink:label="loc_us-gaapSalariesAndWages" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSalariesAndWages" order="10" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_MultiemployerPlansEmployeesIncreaseDecreasePercentageSalaries" xlink:label="loc_solarmaxMultiemployerPlansEmployeesIncreaseDecreasePercentageSalaries" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxMultiemployerPlansEmployeesIncreaseDecreasePercentageSalaries" order="11" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DescriptionOfRevenues" xlink:label="loc_solarmaxDescriptionOfRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDescriptionOfRevenues" order="12" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/StockholdersEquityDeficitDetails" xlink:title="995530 - Disclosure - Stockholders Equity (Deficit) (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/StockholdersEquityDeficitDetailsNarrative" xlink:title="995531 - Disclosure - Stockholders Equity (Deficit) (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaapSubsidiarySaleOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapSubsidiarySaleOfStockAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaapSaleOfStockNameOfTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapSubsidiarySaleOfStockAxis" xlink:to="loc_us-gaapSaleOfStockNameOfTransactionDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaapSaleOfStockNameOfTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapSubsidiarySaleOfStockAxis" xlink:to="loc_us-gaapSaleOfStockNameOfTransactionDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrivatePlacementMember" xlink:label="loc_us-gaapPrivatePlacementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSaleOfStockNameOfTransactionDomain" xlink:to="loc_us-gaapPrivatePlacementMember" order="1031" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ReverseStockSplitMember" xlink:label="loc_solarmaxReverseStockSplitMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_solarmaxReverseStockSplitMember" order="1032" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="loc_us-gaapSaleOfStockConsiderationReceivedOnTransaction" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSaleOfStockConsiderationReceivedOnTransaction" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConversionOfStockDescription" xlink:label="loc_us-gaapConversionOfStockDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapConversionOfStockDescription" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ReverseSplitCommonStockOutstandingSharesDescription" xlink:label="loc_solarmaxReverseSplitCommonStockOutstandingSharesDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxReverseSplitCommonStockOutstandingSharesDescription" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityReverseStockSplit" xlink:label="loc_us-gaapStockholdersEquityReverseStockSplit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquityReverseStockSplit" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ExtentedPeriodOfGrantedOptions" xlink:label="loc_solarmaxExtentedPeriodOfGrantedOptions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxExtentedPeriodOfGrantedOptions" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharePrice" xlink:label="loc_us-gaapSharePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharePrice" order="7" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_PurchasePriceDescription" xlink:label="loc_solarmaxPurchasePriceDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxPurchasePriceDescription" order="8" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/IncomeTaxesDetails" xlink:title="995532 - Disclosure - Income Taxes (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/IncomeTaxesDetailsNarrative" xlink:title="995533 - Disclosure - Income Taxes (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/NetIncomeLossPerShareDetails" xlink:title="995534 - Disclosure - Net Income (Loss) Per Share (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/NetIncomeLossPerShareDetailsNarrative" xlink:title="995535 - Disclosure - Net Income (Loss) Per Share (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/SegmentReportingDetails" xlink:title="995536 - Disclosure - Segment Reporting (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsConsolidationItemsAxis" xlink:label="loc_us-gaapSubsegmentsConsolidationItemsAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapSubsegmentsConsolidationItemsAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsConsolidationItemsDomain" xlink:label="loc_us-gaapSubsegmentsConsolidationItemsDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapSubsegmentsConsolidationItemsAxis" xlink:to="loc_us-gaapSubsegmentsConsolidationItemsDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsConsolidationItemsDomain" xlink:label="loc_us-gaapSubsegmentsConsolidationItemsDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapSubsegmentsConsolidationItemsAxis" xlink:to="loc_us-gaapSubsegmentsConsolidationItemsDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportableSubsegmentsMember" xlink:label="loc_us-gaapReportableSubsegmentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSubsegmentsConsolidationItemsDomain" xlink:to="loc_us-gaapReportableSubsegmentsMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LongTermEpcBessContractsRevenue" xlink:label="loc_solarmaxLongTermEpcBessContractsRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLongTermEpcBessContractsRevenue" order="1" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SolarEnergySystemsRevenue" xlink:label="loc_solarmaxSolarEnergySystemsRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxSolarEnergySystemsRevenue" order="2" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_BatteryOnlySalesRevenue" xlink:label="loc_solarmaxBatteryOnlySalesRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxBatteryOnlySalesRevenue" order="3" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_LedOperationsRevenue" xlink:label="loc_solarmaxLedOperationsRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxLedOperationsRevenue" order="4" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_TotalSegmentRevenue" xlink:label="loc_solarmaxTotalSegmentRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxTotalSegmentRevenue" order="5" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_FinanceRevenues" xlink:label="loc_solarmaxFinanceRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxFinanceRevenues" order="6" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OtherNonCoreRevenue" xlink:label="loc_solarmaxOtherNonCoreRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxOtherNonCoreRevenue" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRevenues" order="8" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_DirectAndIndirectCostsOperatingExpenses" xlink:label="loc_solarmaxDirectAndIndirectCostsOperatingExpenses" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxDirectAndIndirectCostsOperatingExpenses" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LegalFees" xlink:label="loc_us-gaapLegalFees" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLegalFees" order="10" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_SubcontractorsCosts" xlink:label="loc_solarmaxSubcontractorsCosts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxSubcontractorsCosts" order="11" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_CommissionsAndLenderFees" xlink:label="loc_solarmaxCommissionsAndLenderFees" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxCommissionsAndLenderFees" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeBenefitsAndShareBasedCompensation" xlink:label="loc_us-gaapEmployeeBenefitsAndShareBasedCompensation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapEmployeeBenefitsAndShareBasedCompensation" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseCost" xlink:label="loc_us-gaapOperatingLeaseCost" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLeaseCost" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralInsuranceExpense" xlink:label="loc_us-gaapGeneralInsuranceExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapGeneralInsuranceExpense" order="15" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaapSellingAndMarketingExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSellingAndMarketingExpense" order="16" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProfessionalAndContractServicesExpense" xlink:label="loc_us-gaapProfessionalAndContractServicesExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProfessionalAndContractServicesExpense" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaapOperatingExpenses" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingExpenses" order="18" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OtherCorporateOverheadExpense" xlink:label="loc_solarmaxOtherCorporateOverheadExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxOtherCorporateOverheadExpense" order="19" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ProvisionForVariousReserves" xlink:label="loc_solarmaxProvisionForVariousReserves" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxProvisionForVariousReserves" order="20" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaapInterestExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInterestExpense" order="21" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_OtherGainsAndIncome" xlink:label="loc_solarmaxOtherGainsAndIncome" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxOtherGainsAndIncome" order="22" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_ChinaOtherExpenses" xlink:label="loc_solarmaxChinaOtherExpenses" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxChinaOtherExpenses" order="23" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_EliminationAdjustment" xlink:label="loc_solarmaxEliminationAdjustment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxEliminationAdjustment" order="24" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" order="25" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://solarmax.com/role/SubsequentEventsDetailsNarrative" xlink:title="995537 - Disclosure - Subsequent Events (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeAxis" xlink:label="loc_us-gaapShortTermDebtTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapShortTermDebtTypeAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapShortTermDebtTypeAxis" xlink:to="loc_us-gaapShortTermDebtTypeDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapShortTermDebtTypeAxis" xlink:to="loc_us-gaapShortTermDebtTypeDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaapSubsequentEventTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapSubsequentEventTypeAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaapSubsequentEventTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapSubsequentEventTypeAxis" xlink:to="loc_us-gaapSubsequentEventTypeDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaapSubsequentEventTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapSubsequentEventTypeAxis" xlink:to="loc_us-gaapSubsequentEventTypeDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableMember" xlink:label="loc_us-gaapConvertibleNotesPayableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtTypeDomain" xlink:to="loc_us-gaapConvertibleNotesPayableMember" order="1031" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaapSubsequentEventMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSubsequentEventTypeDomain" xlink:to="loc_us-gaapSubsequentEventMember" order="1032" />
    <link:loc xlink:type="locator" xlink:href="solarmax-20260630.xsd#solarmax_RelatedPartiesPrincipalAmount" xlink:label="loc_solarmaxRelatedPartiesPrincipalAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_solarmaxRelatedPartiesPrincipalAmount" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentIssuedPrincipal" xlink:label="loc_us-gaapDebtInstrumentIssuedPrincipal" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentIssuedPrincipal" order="2" />
  </link:definitionLink>
</link:linkbase>
