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ECM Power Source Circuit [10/2015 - ]: Procedure

  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY) 
    GTY684723Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to No. 1 integration relay)
    1. Remove the No. 1 integration relay from No. 2 engine room relay block.
    2. Measure the voltage according to the value (s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2D-1 - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - NO. 1 INTEGRATION RELAY) 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY) 
    1. Remove the No. 1 integration relay from No. 2 engine room relay block.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2E-16 - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN, IG2 RELAY) 
    1. Inspect the No. 1 integration relay (EFI MAIN, IG2 relay).

      Refer to INSPECTION [10/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 1 INTEGRATION RELAY. Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (ECM - NO. 1 INTEGRATION RELAY) 
    1. Disconnect the A12 ECM connector.
    2. Remove the No. 1 integration relay from No. 2 engine room relay block.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A12-3 (MREL) - 2E-8 Always Below 1 Ω
      A12-7 (+B) - 2F-2 Always Below 1 Ω
      A12-6 (+B2) - 2F-1 Always Below 1 Ω
      A12-3 (MREL) or 2E-8 - Body ground and other terminals Always 10 kΩ or higher
      A12-7 (+B) or 2F-2 - Body ground and other terminals Always 10 kΩ or higher
      A12-6 (+B2) or 2F-1 - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E3 ECM connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E3-1 (E1) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT ECM (IGSW VOLTAGE) 
    GTY611910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (ECM)
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value (s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A12-15 (IGSW) - E3-1 (E1) Engine switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [10/2015 - 09/2017]  , or refer to  REMOVAL [09/2017 - ] 

    Result: 

    NG 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (ECM - NO. 1 INTEGRATION RELAY) 
    1. Disconnect the A12 ECM connector.
    2. Remove the No. 1 integration relay from No. 2 engine room relay block.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A12-15 (IGSW) - 2F-7 Always Below 1 Ω
      A12-15 (IGSW) or 2F-7 - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 1 INTEGRATION RELAY) 
    1. Disconnect the A21 certification ECU (smart key ECU assembly) connector.
    2. Remove the No. 1 integration relay from No. 2 engine room relay block.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A21-9 (IG2D) - 2E-5 Always Below 1 Ω
      A21-9 (IG2D) or 2E-5 - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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