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

  1. CHECK FOR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Smart Access, Power Source Control / Trouble Codes.
    5. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2019 - ]

      Result

      Result Proceed to
      DTCs are not output A
      Smart access system with push-button start (for Start Function) DTCs are output B

    Result: 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2019 - 08/2021]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2021 - 08/2022]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2022 - ] 

    Result: 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (DRIVER SIDE JUNCTION BLOCK ASSEMBLY - POWER SUPPLY) 
    1. Disconnect the driver side junction block assembly connector.
      GTY955685Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Driver Side Junction Block Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      5K-1 - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT DRIVER SIDE JUNCTION BLOCK ASSEMBLY 
    GTY956199Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component without harness connected
    (Driver Side Junction Block Assembly)
    - -
    1. Remove the driver side junction block assembly.

      Refer to REMOVAL [08/2019 - ]

    2. Remove the main body ECU (multiplex network body ECU) from the driver side junction block assembly.
    3. Connect a positive (+) lead from the battery to terminal 5A-23.
    4. Connect a negative (-) lead from the battery to terminal 5D-1
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      5K-1 - 5A-49 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2019 - 08/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2020 - 08/2021]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2021 - 08/2022]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2022 - ] 

    Result: 

    NG 

    REPLACE DRIVER SIDE JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [08/2019 - ]