STEERING LOCK SYSTEM Unable to Unlock Steering Wheel (Engine cannot Start)

DESCRIPTION

The steering lock actuator activates the steering lock motor and moves the lock bar into the steering column to lock the steering wheel.

The steering may not unlock when the lock bar gets stuck in the lock hole of the steering column. In this case, if an engine start operation is performed while shaking the steering wheel in the same manner as is done for a vehicle with a mechanical key, the lock bar will be unlocked. If the certification ECU (smart key ECU assembly), ID code box (immobiliser code ECU) or ECM is replaced, the system needs to be initialized. Otherwise, the steering cannot be unlocked and the engine cannot be started, refer to the Service Bulletin.

Related Data List and Active Test Items
Problem Symptom Data List Item Active Test Item
Unable to unlock steering wheel (Engine cannot start)
-

WIRING DIAGRAM

A01VG84E03

CAUTION / NOTICE / HINT

Note


  • When using the intelligent tester with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the intelligent tester and vehicle begins, or 2) connect the intelligent tester to the vehicle and select "MANUAL" from the initial screen on the intelligent tester, and then select "KEY REGIST" under Model Code.

  • The steering lock system uses LIN communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting Click here.

  • Before replacing the steering lock actuator assembly (steering lock ECU), certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU), refer to the Service Bulletin.

  • Perform either of the following operations to lock/unlock the steering:


    • To unlock the steering, carry the key and turn the engine switch on (ACC) or on (IG) while the shift lever is in P*1 or N*2.

    • To lock the steering, turn the engine switch off with the shift lever in P*1 or N*2, and then open a door.

  • After completing repairs, confirm that the problem does not occur.

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

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

  • When disconnecting the cable from the negative (-) battery terminal, some systems need to be initialized after the cable is reconnected Click here.

  • If the steering lock actuator assembly (steering lock ECU) is replaced, be sure to confirm that the steering is unlocked by turning the steering wheel to the left and right before starting the engine. If the steering is locked for any reason, open and close a door with the engine switch off, and then unlock the steering by pressing the engine switch. This prevents the engine from starting while the steering is locked.


  • *1: for CVT

  • *2: for Multi-Mode Manual Transaxle

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*1 or clutch pedal*2 released causes the power source mode to change as follows:

        OK
        Off → on (ACC) → on (IG) → off

        • *1: for CVT or Multi-Mode Manual Transaxle

        • *2: for Manual Transaxle


    NG
    OK
  2. READ VALUE USING INTELLIGENT TESTER (UNLOCK REQUEST RECEIVE)


    1. Use the Data List to check if the steering lock command is functioning properly.

      Entry & Start
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Unlock Request Receive

      Reception state of steering unlock command signal determined by certification ECU (smart key ECU assembly) and sent to ID code box (immobiliser code ECU) / OK or NG

      Tech Tips


      • 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 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.

      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".

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. Disconnect the F61 steering lock actuator assembly (steering lock ECU) connector.

    2. A01VIH4E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Steering Lock Actuator Assembly (Steering Lock ECU))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F61-1 (GND) - Body ground Always Below 1 Ω

      Note

      If the result is not as specified, check for looseness in the connection which leads to ground.

      Standard Voltage
      Tester Connection Condition Specified Condition
      F61-7 (B) - Body ground Always 11 to 14 V

    NG
    OK
  4. CHECK STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) (IGE VOLTAGE)


    1. Reconnect the F61 steering lock ECU connector.

    2. A01VK32E02
      Text in Illustration
      *a

      Component with harness connected

      (Steering Lock ECU (Steering Lock Actuator Assembly))

      *b Steering lock motor not operating
      *c Steering lock motor operating

      Check the signal waveform according to the condition(s) in the table below.

      Standard Frequency
      Item Content
      Tester Connection F61-3 (IGE) - F61-1 (GND)
      Tool Setting 2 V/DIV., 200 ms./DIV.
      Vehicle Condition Steering lock motor not operating → Steering lock motor operating → Steering lock motor not operating

      Tech Tips


      • 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) while the shift lever is in P*1 or N*2.

        • To lock the steering, turn the engine switch off with the shift lever is in P*1 or N*2, and then open a door.


          • *1: for CVT

          • *2: for Multi-Mode Manual Transaxle

      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    A
    B
    C
  5. READ VALUE USING INTELLIGENT TESTER (S CODE CHECK)


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

      Entry & Start
      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 ID code box (immobiliser code ECU) or certification ECU (smart key ECU assembly) is not registered or the ID code box (immobiliser code ECU) or certification ECU (smart key ECU assembly) is malfunctioning.

      • The steering cannot be locked.

      • The steering cannot be unlocked (the engine cannot be started).

      OK
      OK is displayed on the intelligent tester.

      Tech Tips

      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.


    NG
    OK
  6. READ VALUE USING INTELLIGENT TESTER (L CODE CHECK)


    1. Use the Data List to check if L code certification is functioning properly.

      Entry & Start
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobiliser code ECU) and 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 actuator assembly (steering lock ECU) is not registered or the ID code box (immobiliser code ECU) or steering lock actuator assembly (steering lock ECU) is malfunctioning.

      • The steering cannot be locked.

      • The steering cannot be unlocked (the engine cannot be started).

      OK
      OK is displayed on the intelligent tester.

      Tech Tips

      Reasons for verification failure:


      • The steering lock actuator assembly (steering lock ECU) 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.


    NG
    OK
  7. REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU)


    1. Replace the steering lock actuator assembly (steering lock ECU) with a new one.

      Tech Tips


    2. Perform the registration procedures (Refer to Service Bulletin for registration).

    3. Turn the engine switch on (IG).

    4. Operate the steering wheel and check the steering condition.

      OK
      Steering is unlocked.

    OK
    NG
  8. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)


    1. Replace the ID code box (immobiliser code ECU) with a new one.

    2. Perform the registration procedures (Refer to Service Bulletin for registration).

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

      Entry & Start
      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 ID code box (immobiliser code ECU) or certification ECU (smart key ECU assembly) is not registered or the ID code box (immobiliser code ECU) or certification ECU (smart key ECU assembly) is malfunctioning.

      • The steering cannot be locked.

      • The steering cannot be unlocked (the engine cannot be started).

      OK
      OK is displayed on the intelligent tester.

    OK
    NG
  9. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)


    1. Replace the ID code box (immobiliser code ECU) with a new one.

    2. Perform the registration procedures (Refer to Service Bulletin for registration).

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

      Entry & Start
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobiliser code ECU) and 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 actuator assembly (steering lock ECU) is not registered or the ID code box (immobiliser code ECU) or steering lock actuator assembly (steering lock ECU) is malfunctioning.

      • The steering cannot be locked.

      • The steering cannot be unlocked (the engine cannot be started).

      OK
      OK is displayed on the intelligent tester.
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    A
    B
    C