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

DTC Code DTC Name
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, ID code box 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.

WIRING DIAGRAM

C202123E22

INSPECTION PROCEDURE

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.

  • 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.

    • To lock the steering, turn the engine switch off with the shift lever in P, 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 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.

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

Tip:
Table 1. Related Data List and Active Test Items

Problem Symptom

Data List Item

Active Test Item

Unable to unlock steering wheel (Engine cannot start)

-

Click here

PROCEDURE

  1. CHECK DTC (ALL)

    1. Using the intelligent tester, confirm the output of DTCs for all systems.

      OK

      No DTCs are output.

      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.

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

        Click here

      Result

      Result

      OK

      NG

    Body Electrical > Entry&Start > Trouble Codes

    NG

    GO TO DTC CHART

    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 released causes the power source mode to change as follows:

        OK

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

        Result

        Result

        OK

        NG
    NG

    GO TO ENTRY AND START SYSTEM (FOR START FUNCTION) (PROBLEM SYMPTOMS TABLE)

    Click here

    OK

  3. READ VALUE USING INTELLIGENT TESTER (UNLOCK REQUEST RECEIVE)

    1. Use the Data List to check if the steering lock command 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 command signal determined by certification ECU and sent to ID code box

      • HINT:

      • The reception state is maintained for 10 seconds.

      NG or OK

      OK: Within 10 seconds of turning engine switch on (IG) or on (ACC) or starting engine

      NG: Except above

      When 10 seconds or more elapse after the signal is received, the item changes to "NG".

      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

      OK

      NG
    NG

    READ VALUE USING INTELLIGENT TESTER (S CODE CHECK)Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - BATTERY AND BODY GROUND)

    1. Disconnect the G23 steering lock ECU connector.

    2. C202099C01

      *a

      Front view of wire harness connector

      (to Steering Lock ECU)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      G23-1 (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

      G23-7 (B) - Body ground

      Always

      11 to 14 V

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT STEERING LOCK ECU (IGE VOLTAGE)

    1. Reconnect the G23 steering lock ECU connector.

    2. C222662C01

      *a

      Component with harness connected

      (Steering Lock ECU)

      *b

      Steering lock motor not operating

      *c

      Steering lock motor operating

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

      Table 2. Standard Frequency

      Item

      Content

      Tester Connection

      G23-3 (IGE) - G23-1 (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
      Tip:

      • 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.

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

      Result

      Result

      OK

      NG
    OK

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU)

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. READ VALUE USING INTELLIGENT TESTER (S CODE CHECK)

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

      Body Electrical > Entry&Start > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      S Code Check

      Verification result between certification ECU and ID code box

      NG or OK

      OK: Verification result normal

      NG: Verification result abnormal

      -

      OK

      OK is displayed on the intelligent tester.

      Tip:

      Reasons for verification failure:

      • The certification ECU or ID code box 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

      Result

      OK

      NG
    NG

    REPLACE CERTIFICATION ECUClick here

    OK

  7. READ VALUE USING INTELLIGENT TESTER (L CODE CHECK)

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

      Body Electrical > Entry&Start > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      L Code Check

      Verification result between ID code box and steering lock actuator assembly

      NG or OK

      OK: Verification result normal

      NG: Verification result abnormal

      -

      OK

      OK is displayed on the intelligent tester.

      Tip:

      Reasons for verification failure:

      • The steering lock ECU or ID code box 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

      Result

      OK

      NG
    NG

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU)Click here

    OK

  8. REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU)

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

      Click here

    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.

      Result

      Result

      OK

      NG
    OK

    END

    NG

    REPLACE CERTIFICATION ECU

  9. REPLACE CERTIFICATION ECU

    1. Replace the certification 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.

      Body Electrical > Entry&Start > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      S Code Check

      Verification result between certification ECU and ID code box

      NG or OK

      OK: Verification result normal

      NG: Verification result abnormal

      -

      OK

      OK is displayed on the intelligent tester.

      Result

      Result

      OK

      NG
    OK

    END

    NG

    REPLACE ID CODE BOX

  10. REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU)

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

      Click here

    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.

      Body Electrical > Entry&Start > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      L Code Check

      Verification result between ID code box and steering lock actuator assembly

      NG or OK

      OK: Verification result normal

      NG: Verification result abnormal

      -

      OK

      OK is displayed on the intelligent tester.

      Result

      Result

      OK

      NG
    OK

    END

    NG

    REPLACE ID CODE BOX