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ECM Power Source Circuit [09/2014 - ]: Procedure

  1. INSPECT SEMICONDUCTOR POWER INTEGRATION ECU (POWER SOURCE) 
    GTY461790Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Semiconductor Pwr Integration ECU)
    1. Disconnect the semiconductor pwr integration ECU connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

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

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - SEMICONDUCTOR PWR INTEGRATION ECU) 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - BODY GROUND) 
    1. Disconnect the semiconductor pwr integration ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2D-14 - Body ground Always Below 1 Ω
      2G-5 - 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 SEMICONDUCTOR POWER INTEGRATION ECU (EFI-MAIN, IG2 RELAY) 
    1. Inspect the semiconductor pwr integration ECU (EFI-MAIN, IG2 relay).

      Refer to INSPECTION [09/2014 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE SEMICONDUCTOR POWER INTEGRATION ECU. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (ECM - SEMICONDUCTOR PWR INTEGRATION ECU) 
    1. Disconnect the ECM connector.
    2. Disconnect the semiconductor pwr integration ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A77-3 (MREL) - 2G-6 Always Below 1 Ω
      A77-7 (+B) - 2G-8 Always Below 1 Ω
      A77-6 (+B2) - 2G-7 Always Below 1 Ω
      A77-3 (MREL) or 2G-6 - Body ground Always 10 kΩ or higher
      A77-7 (+B) or 2G-8 - Body ground Always 10 kΩ or higher
      A77-6 (+B2) or 2G-7 - Body ground 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 ECM connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F4-1 (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) 
    GTY499814Courtesy 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 Condition Specified Condition
      A77-15 (IGSW) - F4-1 (E1) Engine switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    NG 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (ECM - SEMICONDUCTOR PWR INTEGRATION ECU) 
    1. Disconnect the ECM connector.
    2. Disconnect the semiconductor pwr integration ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A77-15 (IGSW) - 2F-4 Always Below 1 Ω
      A77-15 (IGSW) or 2F-4 - Body ground 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 - SEMICONDUCTOR PWR INTEGRATION ECU) 
    1. Disconnect the certification ECU (smart key ECU assembly) connector.
    2. Disconnect the semiconductor pwr integration ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A13-3 (IG1D) - 2E-1 Always Below 1 Ω
      A13-3 (IG1D) or 2E-1 - Body ground 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 [09/2014 - 01/2023]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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