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Unable to Unlock Steering Wheel (Engine cannot Start) [08/2015 - 08/2019]: Procedure

  1. CHECK ENGINE SWITCH (SWITCH CONDITION) 
    1. Check the power source mode change.
      1. When the key is inside the vehicle and the shift lever is in P, check that pressing the engine switch causes the power source mode to change as follows:

        OK

        off → on (ACC) → on (IG) → off

    Result: 

    NG 

    GO TO SMART KEY SYSTEM (FOR START FUNCTION) (PROBLEM SYMPTOMS TABLE) 

    (Refer to PROBLEM SYMPTOMS TABLE [08/2015 - 08/2019] )

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) 
    1. Use the Data List to check if the steering lock command is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Unlock Request Receive Steering lock unlock command reception status/NG or OK NG: Unlock request not received
      OK: Unlock request received
      -

      OK

      The certification ECU receives an unlock request signal within 10 seconds of starting the engine, and OK is displayed on the Techstream screen.

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the F68 steering lock ECU connector.
      GTY703247Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance and voltage according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F68-1 (GND) - Body ground Always Below 1 Ω

      Standard Voltage

      Tester Connection Condition Specified Condition
      F68-7 (B) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Steering Lock ECU)

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. INSPECT STEERING LOCK ECU (IGE VOLTAGE) 
    1. Move the shift lever to P.
      GTY691242Courtesy 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
      F68-3 (IGE) - F68-1 (GND) Steering lock motor operating immediately after turning engine switch from off to on (IG) Below 1 V
      F68-3 (IGE) - F68-1 (GND) Steering lock motor not operating 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Steering Lock ECU)

    Result: 

    OK 

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) 

    (Refer to DISASSEMBLY [08/2015 - 08/2022] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. READ VALUE USING TECHSTREAM (S CODE CHECK) 
    1. Use the Data List to check if the S code certification is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      S Code Check S code certification result/NG or OK OK: S code certification result normal
      NG: S code certification result abnormal
      -

      OK

      OK is displayed on the Techstream.

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  6

  6. READ VALUE USING TECHSTREAM (L CODE CHECK) 
    1. Use the Data List to check if the L code certification is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check L code certification result/NG or OK OK: L code certification result normal
      NG: L code certification result abnormal
      -

      OK

      OK is displayed on the Techstream.

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  7

  7. REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) 
    1. Replace the steering lock actuator assembly (steering lock ECU) (Refer to DISASSEMBLY [08/2015 - 08/2022] ).

    Result: 

    NEXT 

    See step  8

  8. CHECK STEERING LOCK RELEASE OPERATION 
    1. Turn the engine switch on (IG).
    2. Operate the steering wheel and check the steering lock condition.

      OK

      Steering lock is released.

    Result: 

    OK 

    END (STEERING LOCK ECU IS DEFECTIVE) 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU 

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

  9. REPLACE ID CODE BOX 
    1. Replace the ID code box (Refer to REMOVAL [08/2015 - ] ).

    Result: 

    NEXT 

    See step  10

  10. READ VALUE USING TECHSTREAM (S CODE CHECK) 
    1. Use the Data List to check if the S code certification is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      S Code Check S code certification result/NG or OK OK: S code certification result normal
      NG: S code certification result abnormal
      -

      OK

      OK is displayed on the Techstream.

    Result: 

    OK 

    END (ID CODE BOX IS DEFECTIVE) 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU 

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

  11. REPLACE ID CODE BOX 
    1. Replace the ID code box (Refer to REMOVAL [08/2015 - ] ).

    Result: 

    NEXT 

    See step  12

  12. READ VALUE USING TECHSTREAM (L CODE CHECK) 
    1. Use the Data List to check if the L code certification is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check L code certification result/NG or OK OK: L code certification result normal
      NG: L code certification result abnormal
      -

      OK

      OK is displayed on the Techstream.

    Result: 

    OK 

    END (ID CODE BOX IS DEFECTIVE) 

    Result: 

    NG 

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) 

    (Refer to DISASSEMBLY [08/2015 - 08/2022] )