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Power Source Mode does not Change to ON (IG) [12/2019 - 11/2023]: Procedure

  1. CHECK FOR DTC 
    1. Using the GTS, check for certification ECU (smart key ECU assembly) DTCs.

      Body Electrical > Power Source Control > Trouble Codes 

      Body Electrical > Smart Key > Trouble Codes 

      Body Electrical > Starting Control > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      Smart key system (for Start Function) DTCs are output B

    Result: 

    B 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [12/2019 - 10/2021]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2021 - 10/2022]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2022 - 11/2023] 

    Result: 

    A 

    See step  2

  2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY873300Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      H48-17 (IG1D) - Body ground Ignition switch off → Ignition switch ACC 1 V or less → 9 V or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2019 - 11/2023] 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the 4A, 4B, 4E and 4F instrument panel junction block assembly connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H48-17 (IG1D) - 4A-17 Always Below 1 Ω
      4B-3 - Body ground Always Below 1 Ω
      H48-17 (IG1D) or 4A-17 - Other terminals and body ground Always 10 kΩ or higher
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      4F-1 - Body ground Always 11 to 14 V
      4E-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  4

  4. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (IG1-NO. 1, IG1-NO. 2, IG2-NO. 2 RELAY) 
    1. Remove the instrument panel junction block assembly.

      Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023]

    2. Connect all of the instrument panel junction block assembly connectors.
    3. Connect the H48 certification ECU (smart key ECU assembly) connector.
    4. Measure the voltage according to the value(s) in the table below.
      GTY898324Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Instrument Panel Junction Block Assembly)      		 - -

      Standard Voltage

      Tester Connection Condition Specified Condition
      4C-14 - Body ground Ignition switch ON 11 to 14 V
      4D-12 - Body ground Ignition switch ON 11 to 14 V
      4C-15 - Body ground Ignition switch ON 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ] 

    Result: 

    NG 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [12/2019 - 10/2022]  , or refer to  REMOVAL [10/2022 - 11/2023] 

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