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Home >> Subaru >> 2019 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Steering >> Steering Column >> Steering Lock System >> The Steering Lock Does Not Operate (With ID Code Box) >> Inspection steps
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Inspection steps

CAUTION:
  • The steering lock system is equipped with functions that use multiplex communication. Firstly, please follow the directions in "How to troubleshoot" and then perform troubleshooting after confirming that there is no malfunction in the communication system.
  • After repair is completed, confirm that trouble symptoms do not reoccur.
  • Confirm that no diagnostic codes are output. (If diagnostic codes are output, firstly perform a diagnostic code flow chart check.)
  • When replacing the smart key computer ASSY (Collation ECM), the steering lock actuator ASSY (Steering lock ECM) or the ID code box (with ID code box), please check the applicable precautions (Refer to PRECAUTIONS ), and refer to the "Registration manual for immobilizer".
  • After replacing the steering lock actuator ASSY (Steering lock ECM), before starting the engine be sure to turn the steering mechanism to the left and right to confirm that the steering is not locked. If the steering is locked, perform the steering lock procedure (open and close any door when the vehicle is in the IG OFF state) and then unlock the steering (press the push button start switch). With the steering being locked, the engine cannot be started.
  1. Reading the SSM4 data (unlock request reception state)
    1. Use the SSM4 to perform smart key computer ASSY (Collation ECM) data monitoring.
      PART NAME DESCRIPTION

      Item name Description/display range Normal value Remarks
      [Steering lock lock request reception status] Indicates the lock request signal reception state. Display range: OK (10s)/NG OK: When a lock request is received within 10 seconds after any one of the doors is opened while the shifter is in the P position (Transmission A/T) and the vehicle ignition is turned to IG OFF. NG: Other than above If "OK" is not displayed even if the steering lock conditions are satisfied, there may be a smart key computer ASSY (Collation ECM) malfunction.

      Criteria: After changing from IG ON to IG OFF, a lock request signal is received within 10 seconds after any of the doors are opened.

    OK: Go to next step

    NG: Go to Step  7.

  2. Inspection of the steering lock actuator ASSY (Steering lock ECM)
    1. Measure the resistance between the terminals.
      STANDARD VALUE RESISTANCE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      D59-1 (GND) - Chassis ground Always Less than 1 Ω
      CAUTION: If defective, check for ground point looseness. (2) Measure the voltage between the terminals.
      VOLTAGE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      D59-7 (B) - Chassis ground Always 11 to 14 V
      G12591274Courtesy of SUBARU OF AMERICA, INC.

    OK: Go to next step

    NG: Repair or replacement of wiring harness or connector

  3. Inspection of the steering lock actuator ASSY (Steering lock ECM)
    1. Use an oscilloscope to check the waveform between the terminals.
      Item Contents
      Inspection terminals D59-3 (SLR+) - D59-1 (GND)
      Equipment setting 2 V/DIV, 200 ms/DIV
      Inspection conditions Steering lock actuator motor stopped →Steering lock actuator motor running →Steering lock actuator motor stopped
      G12591275Courtesy of SUBARU OF AMERICA, INC.
      NOTE:
      • Lock motor stopped: No operation
      • Lock motor running:
        • Steering unlock:

          The electrical key transmitter SUB-ASSY (Electronic key) is being carried and the vehicle is set to ACC ON or IG ON.

        • Steering lock:

          The door is opened while the shifter is in the P position (Transmission A/T) and the vehicle is set to IG OFF and ACC OFF.

    OK: Go to next step

    NG: Go to Step  10.

  4. Reading the SSM4 data (S code check)
    1. Use the SSM4 to perform smart key computer ASSY (Collation ECM) data monitoring.
      PART NAME DESCRIPTION

      Item name Description/display range Normal value Remarks
      [S Code Check] Verification results between the collation ECM (smart key ECM ASSY) and the ID code box (immobilizer code ECM)/OK or NG. OK: Confirmation results normal NG: Confirmation results abnormal Confirmation results abnormal If abnormal:
      • The ID code box (immobilizer code ECM) or the collation ECM (smart key ECM ASSY) ID codes are not registered, or they are malfunctioning.
      • The steering is not locked.
      • The steering is not unlocked. (The engine cannot be started.)

      Criteria: [S code check] is "OK".

    OK: Go to next step

    NG: Go to Step  12.

  5. Reading the SSM4 data (L code check)
    1. Use the SSM4 to perform smart key computer ASSY (Collation ECM) data monitoring.
      PART NAME DESCRIPTION

      Item name Description/display range Normal value Remarks
      [L Code Check] Indicates the collation results between the smart key computer ASSY (Collation ECM) and the steering lock actuator ASSY (Steering lock ECM).
      Display range: abnormal/normal
      Abnormal: Collation results abnormal
      OK: Collation results normal
      • The smart key computer ASSY (Collation ECM) and the steering lock actuator ASSY (Steering lock ECM) are unable to perform L code registration.
      • Steering lock cannot be performed.
      • Steering unlock cannot be performed. (The engine cannot be started.)

      Criteria: [L code check] is "OK".

      NOTE: Collation fault causes
      • Steering lock actuator ASSY (Steering lock ECM) or smart key computer ASSY (Collation ECM) fault.
      • Communication malfunction between both ECMs.
      • One of the ECMs was replaced and is not yet registered.
      • When replaced with an ECM with a code that has already been written.

    OK: Go to next step

    NG: Go to Step  13.

  6. Replace the steering lock actuator ASSY (Steering lock ECM)
    1. Replace the steering lock actuator (Steering lock ECM) with a new part. (Refer to ASSEMBLY )
    2. Perform registration. (Refer to the "Registration manual for immobilizer")
    3. Turn the ignition switch to ON.
    4. Operate the steering wheel to check the steering lock state.

    Criteria: The steering lock is released.

    OK: Go to next step

    NG: Go to Step  14.

    Complete (Failure of the steering lock actuator ASSY)

  7. Reading the SSM4 data (driver's door courtesy switch)
    1. Use the SSM4 to perform main body ECM (network gateway computer) data monitoring.
      PART NAME DESCRIPTION

      Item name Description/display range Normal value Remarks
      The driver's door courtesy switch State of the driver's door courtesy light switch. Display range: Closed/Open [Close]: Driver's door is closed. [Open]: Driver's door is opened. -

      Criteria: The data monitoring trend changes as the driver's door is opened and closed.

    OK: Go to next step

    NG: Carrying out main body ECM fault diagnosis (Refer to ECM TERMINAL ARRANGEMENT )

  8. Inspection of the smart key computer ASSY (Collation ECM)
    1. Disconnect the smart key computer ASSY (Collation ECM) connector D41.
    2. Disconnect the brake actuator ASSY (skid control computer) connector A5.
    3. Measure the resistance between the terminals.
      STANDARD VALUE RESISTANCE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      D41-27 (SPD) - A5-2 (SPD) Always Less than 1 Ω
      D41-27 (SPD) - A5-2 (SPD) - Chassis ground Always 10 k Ωor more

    OK: Go to next step

    NG: Repair or replacement of wiring harness or connector

  9. Smart key computer ASSY (Collation ECM)
    1. Replace the smart key computer ASSY (Collation ECM) with a new part.
    2. Perform registration. (Refer to the "Registration manual for immobilizer")
    3. Turn the ignition switch to ON.
    4. Use the SSM4 to perform smart key computer ASSY (Collation ECM) data monitoring.
      PART NAME DESCRIPTION

      Item name Description/display range Normal value Remarks
      [Steering lock lock request reception status] Indicates the lock request signal reception state. Display range: NG/OK (10 s) OK: When a lock request is received within 10 seconds after any one of the doors is opened while the shifter is in the P position (Transmission A/T) and the vehicle ignition is turned to IG OFF. NG: Other than above If "OK" is not displayed even if the steering lock conditions are satisfied, there may be a smart key computer ASSY (Collation ECM) malfunction.

      Criteria: After changing from IG ON to IG OFF, a lock request signal is received within 10 seconds after any of the doors are opened.

    OK

    NG: Replace the ID code box (immobilizer ECM)

    Complete (Smart key computer ASSY (Collation ECM) fault)

  10. Inspect the wiring harness and connector (Smart key computer ASSY (Collation ECM) - Steering lock actuator ASSY (Steering lock ECM)).
    1. Disconnect the steering lock actuator (Steering lock ECM) connector D59.
    2. Disconnect the smart key computer ASSY (Collation ECM) connector D41.
    3. Confirm that there is no deformation or corrosion on the connector case and terminal.

      Criteria: There is no deformation or corrosion on the connector case and terminal.

    4. Measure the resistance between the terminals.
      STANDARD VALUE RESISTANCE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      D41-29 (SLR+) - D59-3(SLR+) Always Less than 1 Ω
      D59-3 (SLR+) - Chassis ground Always 10 k Ωor more

    OK: Go to next step

    NG: Repair or replacement of wiring harness or connector

  11. Replacement of the steering lock actuator ASSY (Steering lock ECM)
    1. Replace the steering lock actuator ASSY (Steering lock ECM) with a new part. (Refer to ASSEMBLY )
    2. Perform registration. (Refer to the "Registration manual for immobilizer")
    3. Turn the ignition switch to ON.
    4. Operate the steering wheel to check the steering lock state.

      Criteria: The steering lock is released.

    OK: Go to next step

    NG: Replacement of the smart key computer ASSY (Collation ECM)

    Complete (Failure of the steering lock actuator ASSY)

  12. Replace the ID code box (immobilizer ECM)
    1. Replace the ID code box (immobilizer ECM) with a new part.
    2. Perform registration. (Refer to the "Registration manual for immobilizer").
    3. Turn the ignition switch to ON.
    4. Use the SSM4 to perform smart key computer ASSY (Collation ECM) data monitoring.
      PART NAME DESCRIPTION

      Item name Description/display range Normal value Remarks
      [S Code Check] Verification results between the collation ECM (smart key ECM ASSY) and the ID code box (immobilizer code ECM)/OK or NG. OK: Confirmation results normal NG: Confirmation results abnormal Confirmation results abnormal If abnormal:
      • The ID code box (immobilizer code ECM) or the collation ECM (smart key ECM ASSY) ID codes are not registered, or they are malfunctioning.
      • The steering is not locked.
      • The steering is not unlocked. (The engine cannot be started.)

      Criteria: [S code check] is "OK".

    OK: Go to next step

    NG: Replacement of the smart key computer ASSY (Collation ECM)

    Complete (ID code box (immobilizer ECM) fault)

  13. Replace the ID code box (immobilizer ECM)
    1. Replace the ID code box (immobilizer ECM) with a new part.
    2. Perform registration. (Refer to the "Registration manual for immobilizer").
    3. Turn the ignition switch to ON.
    4. Use the SSM4 to perform smart key computer ASSY (Collation ECM) data monitoring.
      PART NAME DESCRIPTION

      Item name Description/display range Normal value Remarks
      [L Code Check] Display range indicating the collation results between the smart key computer ASSY (Collation ECM) and the steering lock actuator ASSY (Steering lock ECM). abnormal/normal Abnormal: Collation results abnormal: Collation results normal
      • The smart key computer ASSY (Collation ECM) and the steering lock actuator ASSY (Steering lock ECM) are unable to perform L code registration.
      • Steering lock cannot be performed.
      • Steering unlock cannot be performed. (The engine cannot be started).

      Criteria: [L code check] is "OK".

    OK: Go to next step

    NG: Replacement of the steering lock actuator ASSY (Steering lock ECM) (Refer to ASSEMBLY )

    Complete (ID code box (immobilizer ECM) fault)

  14. Replacement of the smart key computer ASSY (Collation ECM)
    1. Replace the smart key computer ASSY (Collation ECM) with a new part.
    2. Perform registration. (Refer to the "Registration manual for immobilizer").
    3. Turn the ignition switch to ON.
    4. Operate the steering wheel to check the steering lock state.

    Criteria: The steering lock is released.

    OK: Go to next step

    NG: Replace the ID code box (immobilizer ECM)

    Complete (Smart key computer ASSY (Collation ECM) fault)