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ECM Power Source Circuit [08/2014 - ]: Procedure

  1. 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
      D27-104 (E1) - Body ground Always Below 1 Ω

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  2

  2. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
      GTY528393Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the power switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A60-28 (IGSW) - Body ground Power switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)

    Result:  NG

    NG 

    See step  7

    Result:  OK

    OK 

    See step  3

  3. INSPECT NO. 2 INTEGRATION RELAY (EFI MAIN RELAY) 
    1. Inspect the No. 2 integration relay (EFI MAIN relay) (See article. Refer to INSPECTION [08/2014 - ] ).

    Result:  NG

    NG 

    REPLACE NO. 2 INTEGRATION RELAY (EFI MAIN RELAY) 

    (See article. Refer to REMOVAL [08/2014 - ] )

    Result:  OK

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY (EFI MAIN RELAY) - ECM) 
    1. Remove the No. 2 integration relay (EFI MAIN relay) from the engine room relay block and junction block assembly.
    2. Disconnect the No. 2 integration relay connector.
    3. Disconnect the ECM connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1B-4 - A60-1 (+B2) Always Below 1 Ω
      1B-4 - A60-2 (+B) Always Below 1 Ω
      1B-2 - A60-6 (MREL) Always Below 1 Ω

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY (EFI MAIN RELAY) - AUXILIARY BATTERY) 
    1. Remove the No. 2 integration relay (EFI MAIN relay) from the engine room relay block and junction block assembly.
    2. Disconnect the No. 2 integration relay connector.
    3. Disconnect the negative (-) auxiliary battery terminal.
    4. Disconnect the positive (+) auxiliary battery terminal.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1C-1 - Positive (+) auxiliary battery terminal Always Below 1 Ω

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY (EFI MAIN RELAY) - BODY GROUND) 
    1. Remove the No. 2 integration relay (EFI MAIN relay) from the engine room relay block and junction block assembly.
    2. Disconnect the No. 2 integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1B-3 - Body ground Always Below 1 Ω

    Result:  OK

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

    (See article. Refer to PROBLEM SYMPTOMS TABLE [08/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  7. INSPECT NO. 2 INTEGRATION RELAY (IG2 RELAY) 
    1. Inspect the No. 2 integration relay (IG2 relay) (See article. Refer to INSPECTION [08/2014 - ] ).

    Result:  NG

    NG 

    REPLACE NO. 2 INTEGRATION RELAY (IG2 RELAY) 

    (See article. Refer to REMOVAL [08/2014 - ] )

    Result:  OK

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY (IG2 RELAY) - ECM) 
    1. Disconnect the ECM connector.
    2. Remove the No. 2 integration relay (IG2 relay) from the engine room relay block and junction block assembly.
    3. Disconnect the No. 2 integration relay connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1A-4 - A60-28 (IGSW) Always Below 1 Ω
      1A-4 or A60-28 (IGSW) - Body ground Always 10 kΩ or higher

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY (IG2 RELAY) - AUXILIARY BATTERY) 
    1. Remove the No. 2 integration relay (IG2 relay) from the engine room relay block and junction block assembly.
    2. Disconnect the No. 2 integration relay connector.
    3. Disconnect the negative (-) auxiliary battery terminal.
    4. Disconnect the positive (+) auxiliary battery terminal.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1C-1 - Positive (+) auxiliary battery terminal Always Below 1 Ω

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY (IG2 RELAY) - BODY GROUND) 
    1. Remove the No. 2 integration relay (IG2 relay) from the engine room relay block and junction block assembly.
    2. Disconnect the No. 2 integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1A-3 - Body ground Always Below 1 Ω

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - NO. 2 INTEGRATION RELAY (IG2 RELAY)) 
    1. Remove the No. 2 integration relay (IG2 relay) from the engine room relay block and junction block assembly.
    2. Disconnect the No. 2 integration relay connector.
    3. Disconnect the power management control ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A20-2 (IG2D) - 1A-2 Always Below 1 Ω

    Result:  OK

    OK 

    CHECK SMART ACCESS SYSTEM WITH PUSH-BUTTON START (FOR START FUNCTION) 

    (See article. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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