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Unable to Lock Steering Wheel [09/2014 - ]: Procedure

  1. CHECK DTC (ALL) 
    1. Using the Techstream, confirm the output of DTCs for all systems.

      OK

      No DTCs are output.

      NOTE:
      • When using the Techstream with the engine switch off to troubleshoot:

        Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins.

      • Make sure that no DTCs are output. If any DTCs are output, proceed to Diagnostic Trouble Code Chart.

    Result: 

    NG 

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

    Result: 

    OK 

    See step  2

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

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Lock Request Receive Reception state of steering lock request signal by certification ECU (smart key ECU assembly) and sent to ID code box (immobiliser code ECU) / OK or NG
      HINT: 
      • The reception state is maintained for 10 seconds.
      • When 10 seconds or more elapse after receiving the signal, the item changes to "NG".
      		 OK: Within 10 seconds of opening any door with engine switch off and shift lever in P
      NG: Except above      		 If this item does not change to "OK" even though the steering lock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      OK

      The certification ECU (smart key ECU assembly) receives a lock request signal within 10 seconds of turning the engine switch from on (IG) to off and opening a door with the shift lever in P, and OK is displayed on the Techstream screen.

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. INSPECT STEERING LOCK ECU (MOTOR ACTIVATION COMMAND SIGNAL) 

    See step  1

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 

    See step  4

    Result: 

    OK 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    (Refer to DISASSEMBLY [09/2014 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. READ VALUE USING TECHSTREAM (DOOR COURTESY) 
    1. Using the Techstream, check the following main body ECU Data List item by opening and closing the driver door to confirm the state of the front door courtesy light switch assembly.
      MAIN BODY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      FL Door Courtesy SW Front door courtesy light switch assembly LH / ON or OFF OFF: Front door LH closed
      ON: Front door LH open      		 If this item does not change according to the actual state of the driver door, there is a malfunction in the door courtesy light switch or a related part.

      OK

      The Data List item changes in accordance with the opening and closing of the driver door.

    Result: 

    NG 

    GO TO LIGHTING SYSTEM (DOOR COURTESY SWITCH CIRCUIT) 

    (Refer to Door Courtesy Switch Circuit [09/2014 - 10/2015] or refer to Door Courtesy Switch Circuit [10/2015 - ] )

    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.
      SMART ACCESS

      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 NG is displayed:
      • 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).

      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: 

    NG 

    See step  9

    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.
      SMART ACCESS

      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 NG is displayed:
      • 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).

      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: 

    NG 

    See step  10

    Result: 

    OK 

    See step  8

  8. 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 - ] ).
    2. Perform registration procedures (Refer to REGISTRATION [09/2014 - 10/2015] or refer to REGISTRATION [10/2015 - ] ).
    3. Turn the engine switch on (IG).
    4. Turn the steering wheel and check the steering condition.

      OK

      Steering is unlocked.

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL [09/2014 - ] )

  9. 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 procedures (Refer to REGISTRATION [09/2014 - 10/2015] or refer to REGISTRATION [10/2015 - ] ).
    3. Use the Data List to check if S code certification is functioning properly again.
      SMART ACCESS

      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 NG is displayed:
      • 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).

      OK

      OK is displayed on the Techstream.

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [09/2014 - ] )

  10. 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 - ] ).
    2. Perform registration procedures (Refer to REGISTRATION [09/2014 - 10/2015] or refer to REGISTRATION [10/2015 - ] ).
    3. Use the Data List to check if L code certification is functioning properly again.
      SMART ACCESS

      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).

      OK

      OK is displayed on the Techstream.

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [09/2014 - ] )

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