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ECM Power Source Circuit [07/2015 - ]: 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
      D24-16 (E1) - Body ground Always Below 1 Ω

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  2

  2. CHECK TERMINAL VOLTAGE (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
      GTY674283Courtesy 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
      A22-37 (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  6

    Result:  OK

    OK 

    See step  3

  3. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN RELAY) 
    1. Inspect the No. 1 integration relay (EFI MAIN relay). Refer to INSPECTION [07/2015 - ]

    Result:  NG

    NG 

    REPLACE NO. 1 INTEGRATION RELAY (EFI MAIN RELAY) 

    Refer to REMOVAL [07/2015 - ]

    Result:  OK

    OK 

    See step  4

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      1C-9 - A22-2 (+B) Always Below 1 Ω
      1C-10 - A22-3 (+B2) Always Below 1 Ω
      1C-7 - A22-46 (MREL) Always Below 1 Ω
      1C-9 or A22-2 (+B) - Body ground Always 10 kΩ or higher
      1C-10 or A22-3 (+B2) - Body ground Always 10 kΩ or higher
      1C-7 or A22-46 (MREL) - Body ground Always 10 kΩ or higher

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  5

  5. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY) 
    1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
      GTY673969Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1B-1 - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 1 Integration Relay)

    Result:  OK

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

    Refer to PROBLEM SYMPTOMS TABLE [07/2015 - 08/2016] Refer to PROBLEM SYMPTOMS TABLE [08/2016 - ]

    Result:  NG

    NG 

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

  6. INSPECT NO. 1 INTEGRATION RELAY (IG2 RELAY) 
    1. Inspect the No. 1 integration relay (IG2 relay). Refer to INSPECTION [07/2015 - ]

    Result:  NG

    NG 

    REPLACE NO. 1 INTEGRATION RELAY (IG2 RELAY) 

    Refer to REMOVAL [07/2015 - ]

    Result:  OK

    OK 

    See step  7

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      1C-1 - A22-37 (IGSW) Always Below 1 Ω
      1C-1 or A22-37 (IGSW) - Body ground Always 10 kΩ or higher

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  8

  8. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY) 
    1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.
      GTY555735Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1D-3 - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 1 Integration Relay)

    Result:  NG

    NG 

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

    Result:  OK

    OK 

    See step  9

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

      Standard Resistance

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

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  10

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A70-9 (IG2D) - 1C-8 Always Below 1 Ω
      A70-9 (IG2D) or 1C-8 - Body ground Always 10 kΩ or higher

    Result:  OK

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2015 - ]

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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