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Power Source Mode does not Change to ON (IG) [08/2015 - 08/2019]: Procedure

  1. CHECK DTC (ALL) 

    See step  1

    Result: 

    NG 

    GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2015 - 08/2019] 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (BATTERY - POWER MANAGEMENT CONTROL ECU) 
    1. Disconnect the G39 power management control ECU connector.
      GTY649614Courtesy 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
      G39-1 (AM22) - Body ground Always 9.5 to 14 V
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE 

    Result: 

    OK 

    See step  3

  3. INSPECT NO. 1 INTEGRATION RELAY (IG2 RELAY) 
    1. Remove the No. 1 integration relay.
    2. Inspect No. 1 integration relay (Refer to ON-VEHICLE INSPECTION [08/2015 - ] ).

    Result: 

    NG 

    REPLACE NO. 1 INTEGRATION RELAY 

    Result: 

    OK 

    See step  4

  4. INSPECT DRIVER SIDE JUNCTION BLOCK ASSEMBLY (IG1 NO. 1, IG1 NO. 2 AND IG1 NO. 3 RELAYS) 
    1. Disconnect the 2A and 2D driver side junction block assembly connectors.
      GTY634788Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2A-52 - 2D-4 20°C (68°F) 50.63 to 123.75 Ω
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Driver Side Junction Block Assembly)

    Result: 

    NG 

    REPLACE MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY) 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - DRIVER SIDE JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the G39 power management control ECU connector.
    2. Disconnect the 2A driver side junction block assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G39-20 (IG1D) - 2A-52 Always Below 1 Ω
      G39-20 (IG1D) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (DRIVER SIDE JUNCTION BLOCK ASSEMBLY - BODY GROUND) 
    1. Disconnect the 2D driver side junction block assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2D-4 - Body ground Always Below 1 Ω

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - NO. 1 INTEGRATION RELAY) 
    1. Disconnect the G38 power management control ECU connector.
    2. Disconnect the 1A No. 1 integration relay connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G38-8 (IG2D) - 1A-1 Always Below 1 Ω
      G38-8 (IG2D) - 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 (NO. 1 INTEGRATION RELAY - BODY GROUND) 
    1. Disconnect the 1A No. 1 integration relay connector.
    2. 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 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK POWER MANAGEMENT CONTROL ECU 

    See step  3

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2019] )

    Result: 

    NG 

    REPLACE POWER MANAGEMENT CONTROL ECU 

    (Refer to REMOVAL [08/2015 - 08/2019] )

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