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

DESCRIPTION

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

The steering may not unlock when the lock bar gets stuck in the lock hole of the steering column. In this case, if the engine switch is turned on (IG) 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.

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

A012JV4E03

CAUTION / NOTICE / HINT

Note


  • When using the GTS with the vehicle engine switch off, connect the GTS to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry & Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

  • 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) with the shift lever 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.

  • 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

  • After performing repairs, confirm that the problem does not recur.

  • 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 procedure.

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

  • 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 ECU (steering lock actuator assembly) 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. This function prevents the engine from starting while the steering is locked. 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.


  • *1: for CVT

  • *2: for Multi-Mode Manual Transaxle

PROCEDURE


  1. CHECK DTC (ALL)

    Tech Tips

    Click here

    Result
    Proceed to
    OK
    NG

    NG

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

    OK

  2. 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

        • *2: for Multi-Mode Manual Transaxle

      Result
      Proceed to
      OK
      NG

    NG

    GO TO ENTRY AND START SYSTEM (for Start Function) (PROBLEM SYMPTOMS TABLE) Click here

    OK

  3. READ VALUE USING GTS (UNLOCK REQUEST RECEIVE)


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


      Body Electrical > Entry&Start > 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) and sent to ID code box (immobiliser code ECU)

      Tech Tips


      • 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: 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 > Entry&Start > 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
      Result Proceed to
      OK (for CVT) A
      OK (for Multi-Mode Manual Transaxle or Manual Transaxle) B
      NG C

    B

    GO TO STEP 5 Click here

    C

    READ VALUE USING GTS (S CODE CHECK) Click here

    A

  4. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


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

      A012KACC33
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 - -
      Standard Voltage
      Tester Connection Condition Specified Condition
      E35-25 (P) - E33-11 (E) Shift lever in P 9 V or higher
      E35-25 (P) - E33-11 (E) Shift lever not in P 1.5 V or less
      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (SHIFT LOCK CONTROL ECU (SHIFT LOCK CONTROL UNIT ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. Disconnect the E37 steering lock ECU connector.

    2. A012GB5C22
      *a

      Front view of wire harness connector

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E37-1 (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
      E37-7 (B) - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Reconnect the E37 steering lock ECU connector.

    2. A012GWRC15
      *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 E37-3 (IGE) - E37-1 (GND)
      Tool Setting 2 V/DIV., 200 ms./DIV.
      Vehicle Condition Steering lock motor not operating → Operating → 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) with the shift lever 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.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  7. CHECK HARNESS AND CONNECTOR (SHIFT LOCK CONTROL ECU (SHIFT LOCK CONTROL UNIT ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))


    1. Disconnect the E3 shift lock control ECU (shift lock control unit assembly) connector.

    2. Disconnect the E35 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E3-3 (P2) - E35-25 (P) Always Below 1 Ω
      E3-3 (P2) - Body ground Always 10 kΩ or higher
      E35-25 (P) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. INSPECT SHIFT LOCK CONTROL ECU (SHIFT LOCK CONTROL UNIT ASSEMBLY)


    1. Reconnect the E3 shift lock control ECU (shift lock control unit assembly) connector.

    2. A012GY4C03
      *a

      Component with harness connected

      (Shift Lock Control ECU (Shift Lock Control Unit Assembly))

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      E3-3 (P2) - Body ground Shift lever in P 9 V or higher
      E3-3 (P2) - Body ground Shift lever not in P 1.5 V or less
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    NG

    GO TO SHIFT LEVER (INSPECTION) Click here

  9. READ VALUE USING GTS (S CODE CHECK)

    Tech Tips

    Click here

    Result
    Proceed to
    OK
    NG

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

  10. READ VALUE USING GTS (L CODE CHECK)

    Tech Tips

    Click here

    Result
    Proceed to
    OK
    NG

    NG

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY Click here

    OK

  11. REPLACE STEERING LOCK ACTUATOR ASSEMBLY

    Tech Tips

    Click here

    Result
    Proceed to
    OK
    NG

    OK

    END

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

  12. REPLACE STEERING LOCK ACTUATOR ASSEMBLY

    Tech Tips

    Click here

    Result
    Proceed to
    OK
    NG

    OK

    END

    NG

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

  13. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    Tech Tips

    Click here

    Result
    Proceed to
    OK
    NG

    OK

    END

    NG

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)