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Unable to Unlock Steering Wheel (Engine cannot Start) [09/2014 - 01/2023]: 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 with the brake pedal released causes the power source mode to change as follows:

        OK

        Off → On (ACC) → On (IG) → Off

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) (PROBLEM SYMPTOMS TABLE). Refer to  PROBLEM SYMPTOMS TABLE [09/2014 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK INDICATOR 
    1. With the engine switch on (IG), check that Steering Lock active is displayed on the multi-information display in the combination meter assembly.

      Result

      Result Proceed to
      Steering Lock active is displayed. A
      Steering Lock active is not displayed. B

    Result: 

    B 

    See step  4

    Result: 

    A 

    See step  3

  3. CHECK STEERING UNLOCK 
    1. Turn the steering wheel left and right, and then press the engine switch.
    2. Check that the steering is unlocked.

      Result

      Result Proceed to
      The steering is unlocked. A
      The steering is not unlocked. B

    Result: 

    A 

    END 

    Result: 

    B 

    See step  4

  4. CHECK FOR DTC 
    1. Using the Techstream, check if the certification ECU (smart key ECU assembly) DTC is output.

      Body Electrical > Smart Access > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output. A
      DTCs are output. B

    Result: 

    B 

    GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC 

    Result: 

    A 

    See step  5

  5. READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) 
    1. Use the Data List to check if the steering lock request is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Unlock Request Receive Reception state of steering unlock request signal by certification ECU (smart key ECU assembly) sent to ID code box (immobiliser code ECU)
      HINT: 
      • The reception state is maintained for 10 seconds.
      • When 10 seconds or more have elapsed after receiving the signal, the item changes to "NG".
      		 OK or NG OK: Unlock request received within 10 seconds of turning engine switch on (IG) or on (ACC) or starting engine
      NG: Except above
      • If the unlock signal has not been received, the engine cannot be started.
      • If this item does not change to "OK" even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Unlock Request Receive

      OK

      Within 10 seconds of turning the engine switch on (ACC) or on (IG) or starting the engine, the Data List item changes to "OK".

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  14

    Result: 

    OK 

    See step  6

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

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      S Code Check Verification result between certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When a malfunction is present:
      • The ID code for the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is not registered or the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      S Code Check

      OK

      OK is displayed on the Techstream.

      HINT: 

      Reasons for verification failure:

      • The certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • There is a problem with the communication between ECUs.
      • An ECU is replaced, but is not registered.
      • An ECU is replaced with an ECU which has a code already stored in it.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  7

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

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobiliser code ECU) and steering lock ECU (steering lock actuator assembly) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When a malfunction is present:
      • The ID code for the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is not registered or the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      L Code Check

      OK

      OK is displayed on the Techstream.

      HINT: 

      Reasons for verification failure:

      • The steering lock ECU (steering lock actuator assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • There is a problem with the communication between ECUs.
      • An ECU is replaced, but is not registered.
      • An ECU is replaced with an ECU which has a code already stored in it.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  8

  8. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Measure the resistance and voltage according to the value(s) in the table below.
      GTY510565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-1 (GND) - Body ground Always Below 1 Ω
      NOTE:

      If the result is not as specified, check for looseness in the ground cable connection.

      Standard Voltage

      Tester Connection Condition Specified Condition
      O27-7 (B) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (GROUND) 
    1. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY505493Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-1 (GND) - Body ground Always Below 1 Ω
      NOTE:

      If the result is not as specified, check for looseness in the ground cable connection.

    3. Check the signal waveform according to the condition(s) in the table below.
      GTY504133Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))
      *b Steering Lock Motor not Operating
      *c Steering Lock Motor Operating

      Standard Frequency

      Item Content
      Tester Connection O27-3 (IGE) - O27-1 (GND)
      Tool Setting 2 V/DIV., 200 ms./DIV.
      Vehicle Condition Steering lock motor not operating → Operating → Not operating

      HINT: 

      • When taking measurements when the lock motor is stopped, it is not necessary to perform any operations.
      • In order to take measurements when the lock motor is operating, perform either of the following operations:
        • To unlock the steering, carry the key and turn the engine switch on (ACC) or on (IG).
        • To lock the steering, turn the engine switch off with the shift lever in P, and then open a door.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - 03/2019]  , or refer to  DISASSEMBLY [03/2019 - 01/2023] 

    Result: 

    NG 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    2. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    3. Disconnect the O6 certification ECU (smart key ECU assembly) connector.
    4. Check for deformation and corrosion of the connector case and terminals.

      OK

      There is no deformation or corrosion of the connector case or terminals.

    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-3 (IGE) - O6-24 (SLR+) Always Below 1 Ω
      O27-3 (IGE) or O6-24 (SLR+) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  11

  11. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    2. Reconnect the O6 certification ECU (smart key ECU assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY510551Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      O27-3 (IGE) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ] 

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - 03/2019]  , or refer to  DISASSEMBLY [03/2019 - 01/2023] 

  12. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Replace the steering lock ECU (steering lock actuator assembly) with a new one.

      Refer to DISASSEMBLY [09/2014 - 03/2019] , or refer to DISASSEMBLY [03/2019 - 01/2023]

    2. Perform registration.

      Refer to REGISTRATION [09/2014 - 03/2019] , or refer to REGISTRATION [03/2019 - 09/2020] , or refer to REGISTRATION [09/2020 - 01/2023]

    3. Turn the engine switch on (IG).
    4. Use the Data List to check if L code certification is functioning properly again.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobiliser code ECU) and steering lock ECU (steering lock actuator assembly) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When a malfunction is present:
      • The ID code for the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is not registered or the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      L Code Check

      OK

      OK is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [09/2014 - ] 

  13. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one.

      Refer to REMOVAL [09/2014 - ]

    2. Perform registration.

      Refer to REGISTRATION [09/2014 - 03/2019] , or refer to REGISTRATION [03/2019 - 09/2020] , or refer to REGISTRATION [09/2020 - 01/2023]

    3. Use the Data List to check if S code certification is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      S Code Check Verification result between certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When a malfunction is present:
      • The ID code for the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is not registered or the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      S Code Check

      OK

      OK is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [09/2014 - ] 

  14. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY520372Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      O27-4 (SLP1) - Body ground Steering locked 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  17

    Result: 

    OK 

    See step  15

  15. READ VALUE USING TECHSTREAM (STEERING UNLOCK) 
    1. Check that the steering is locked.
    2. Read the Data List according to the display on the Techstream.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Steering Unlock State of whether steering lock ECU (steering lock actuator assembly) determined steering is unlocked Set or Unset Set: Steering unlocked
      Unset: Steering locked      		 If this item displays "Unset", the steering does not unlock (engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      Steering Unlock

      OK

      Set is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - 03/2019]  , or refer to  DISASSEMBLY [03/2019 - 01/2023] 

    Result: 

    OK 

    See step  16

  16. READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one.

      Refer to REMOVAL [09/2014 - ]

    2. Perform registration.

      Refer to REGISTRATION [09/2014 - 03/2019] , or refer to REGISTRATION [03/2019 - 09/2020] , or refer to REGISTRATION [09/2020 - 01/2023]

    3. Turn the engine switch on (IG).
    4. Use the Data List to check if the steering lock request is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Unlock Request Receive Reception state of steering unlock request signal by certification ECU (smart key ECU assembly) sent to ID code box (immobiliser code ECU)
      HINT: 
      • The reception state is maintained for 10 seconds.
      • When 10 seconds or more have elapsed after receiving the signal, the item changes to "NG".
      		 OK or NG OK: Unlock request received within 10 seconds of turning engine switch on (IG) or on (ACC) or starting engine
      NG: Except above
      • If the unlock signal has not been received, the engine cannot be started.
      • If this item does not change to "OK" even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Unlock Request Receive

      OK

      Within 10 seconds of turning the engine switch on (ACC) or on (IG) or starting the engine, the Data List item changes to "OK".

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [09/2014 - ] 

  17. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    2. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    3. Disconnect the O6 certification ECU (smart key ECU assembly) connector.
    4. Check for deformation and corrosion of the connector case and terminals.

      OK

      There is no deformation or corrosion of the connector case or terminals.

    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-4 (SLP1) - O6-23 (SLP) Always Below 1 Ω
      O27-4 (SLP1) or O6-23 (SLP) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  18

  18. READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) 
    1. Replace the steering lock ECU (steering lock actuator assembly) with a new one.

      Refer to DISASSEMBLY [09/2014 - 03/2019] , or refer to DISASSEMBLY [03/2019 - 01/2023]

    2. Perform registration.

      Refer to REGISTRATION [09/2014 - 03/2019] , or refer to REGISTRATION [03/2019 - 09/2020] , or refer to REGISTRATION [09/2020 - 01/2023]

    3. Turn the engine switch on (IG).
    4. Use the Data List to check if the steering lock request is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Unlock Request Receive Reception state of steering unlock request signal by certification ECU (smart key ECU assembly) sent to ID code box (immobiliser code ECU)
      HINT: 
      • The reception state is maintained for 10 seconds.
      • When 10 seconds or more have elapsed after receiving the signal, the item changes to "NG".
      		 OK or NG OK: Unlock request received within 10 seconds of turning engine switch on (IG) or on (ACC) or starting engine
      NG: Except above
      • If the unlock signal has not been received, the engine cannot be started.
      • If this item does not change to "OK" even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Unlock Request Receive

      OK

      Within 10 seconds of turning the engine switch on (ACC) or on (IG) or starting the engine, the Data List item changes to "OK".

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ] 

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