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ECM Power Source Circuit [09/2015 - ]: Procedure

  1. INSPECT INTEGRATION RELAY (POWER SOURCE) 
    1. Disconnect the integration relay connector.
      GTY612147Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      1M-1 - Body ground Always 11 to 14 V

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - INTEGRATION RELAY) 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - BODY GROUND) 
    1. Disconnect the integration relay connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1Q-4 - Body ground Always Below 1 Ω

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT INTEGRATION RELAY (IG2 MAIN, EFI MAIN NO. 1) 
    1. Inspect the integration relay (IG2 MAIN) (Refer to PROCEDURE - Step 2 ).
    2. Inspect the integration relay (EFI MAIN NO. 1) (Refer to PROCEDURE - Step 2 ).

    Result: 

    NG 

    REPLACE INTEGRATION RELAY 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - ECM) 
    1. Disconnect the ECM connector.
    2. Disconnect the integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A38-6 (MREL) - 1Q-8 Always Below 1 Ω
      A38-2 (+B) - 1Q-11 Always Below 1 Ω
      A38-3 (+B2) - 1Q-11 Always Below 1 Ω
      A38-6 (MREL) or 1Q-8 - Body ground Always 10 kΩ or higher
      A38-2 (+B) or 1Q-11 - Body ground Always 10 kΩ or higher
      A38-3 (+B2) or 1Q-11 - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the ECM connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C53-81 (E1) - Body ground Always Below 1 Ω

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connectors.
      GTY646655Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A38-4 (IGSW) - Body ground Engine switch on (IG) 11 to 14 V

    Result: 

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [09/2015 - ] )

    Result: 

    NG 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - ECM) 
    1. Disconnect the ECM connector.
    2. Disconnect the integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A38-4 (IGSW) - 1N-7 Always Below 1 Ω
      A38-4 (IGSW) or 1N-7 - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (SMART KEY ECU ASSEMBLY - NO. 2 INTEGRATION RELAY) 
    1. Disconnect the smart key ECU assembly connector.
    2. Disconnect the integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E149-3 (IG1D) - 1P-2 Always Below 1 Ω
      E149-3 (IG1D) or 1P-2 - Body ground Always 10 kΩ or higher

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2015 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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