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Home >> Subaru >> 2015 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Steering >> Steering Column >> Steering Lock System >> The Steering Lock Cannot Be Released (Cannot Start The Engine) (With ID Code Box) >> Inspection steps
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Inspection steps

CAUTION:
  • Before performing troubleshooting, check the fuse for this circuit.
  • 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 assembly (Collation ECM), the steering lock actuator assembly (Steering lock ECM) or the ID code box (with ID code box), please check the applicable precautions (Refer to PARTS LOCATION ), and refer to the "Registration manual for immobilizer".
  • After replacing the steering lock actuator assembly (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. Operation check (IG ON)
    1. Operate the push button start switch to check whether it can be placed in the IG ON state.

      Criteria: The ignition can be turned to IG ON.

      NG: Go to "Smart entry & start system (smart entry function)" (Symptom table) (Refer to PROBLEM SYMPTOMS TABLE )

      OK: Go to next step

  2. Reading the SSM3 data (unlock request reception state)
    1. Use the SSM3 to perform smart key computer assembly (Collation ECM) data monitoring.

      SSM3 screen: [Each System Check] →[Keyless Access System] →[Collation ECM]→[Current Data Display & Save]

      ITEM DESCRIPTION

      Item name Description/display range Normal value Remarks
      [Steering lock unlock request reception status] Indicates steering lock unlock request signal reception state.
      Display range: NG/OK (10 s)      		 NG: IG ON, ACC ON or engine start operation not performed
      OK: Within 10 seconds after IG ON, ACC ON or engine start operation
      • The engine cannot be started when the unlock request signal cannot be received.
      • If "OK" is not displayed even if the steering unlock conditions are satisfied, there may be a smart key computer assembly (Collation ECM) malfunction.

      Criteria: An unlock request signal is received within 10 seconds after the engine is started.

      NG: Go to Step  8.

      OK: Go to next step

  3. Inspection of the steering lock actuator assembly (Steering lock ECM)
    1. Measure the resistance between the terminals.

      Resistance

      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

      Inspection terminals Inspection conditions Standard value
      D59-7 (B) - Chassis ground Always 11 to 14 V
      Fig 1: Steering Lock Actuator Assembly (Steering Lock ECM) Connector Terminal Identification
      G10215728Courtesy of SUBARU OF AMERICA, INC.

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  4. Inspection of the steering lock actuator assembly (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
      Fig 2: Steering Lock Actuator Assembly (Steering Lock ECM) Connector Terminal Identification With Waveform
      G10215729Courtesy of SUBARU OF AMERICA, INC.
      NOTE:
      • Lock motor stopped: No operation
      • Lock motor running:
        • Steering unlock:

          The electrical key transmitter sub-assembly (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.

      NG: Go to Step  10.

      OK: Go to next step

  5. Reading the SSM3 data (S code check)
    1. Use the SSM3 to perform smart key computer assembly (Collation ECM) data monitoring.

      SSM3 screen: [Each System Check] →[Keyless Access System] →[Collation ECM] →[Current Data Display & Save]

      ITEM DESCRIPTION

      Item name Description/display range Normal value Remarks
      [S Code Check] Verification results between the collation ECM (smart key ECM assembly) and the ID code box (immobilizer code ECM)/OK or NG. OK: Confirmation results normal NG: Confirmation results abnormal If abnormal:
      • The ID code box (immobilizer code ECM) or the collation ECM (smart key ECM assembly) 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".

      NG: Go to Step  12.

      OK: Go to next step

  6. Reading the SSM3 data (L code check)
    1. Use the SSM3 to perform smart key computer assembly (Collation ECM) data monitoring.

      SSM3 screen: [Each System Check] →[Keyless Access System] →[Collation ECM] →[Current Data Display & Save]

      ITEM DESCRIPTION

      Item name Description/display range Normal value Remarks
      [L Code Check] Display range indicating the collation results between the smart key computer assembly (Collation ECM) and the steering lock actuator assembly (Steering lock ECM). abnormal/normal Abnormal: Collation results abnormal: Collation results normal
      • The smart key computer assembly (Collation ECM) and the steering lock actuator assembly (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 assembly (Steering lock ECM) or smart key computer assembly (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.

      NG: Go to Step  13.

      OK: Go to next step

  7. Replacement of the steering lock actuator assembly (Steering lock ECM)
    1. Replace the steering lock actuator (Steering lock ECM) with a new part. (Refer to DISASSEMBLY  )
    2. Perform registration. (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.

      NG: Go to Step  14.

      OK: Complete (Failure of the steering lock actuator assembly)

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

      Resistance

      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 kΩ or more

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  9. Smart key computer assembly (Collation ECM)
    1. Replace the smart key computer assembly (Collation ECM) with a new part.
    2. Carry out the registration settings. (Refer to the "immobilizer registration manual")
    3. Turn the ignition switch to ON.
    4. Use the SSM3 to perform smart key computer assembly (Collation ECM) data monitoring.

      SSM3 screen: [Each System Check] →[Keyless Access System] →[Collation ECM] →[Current Data Display & Save]

      ITEM DESCRIPTION

      Item name Description/display range Normal value Remarks
      [Steering lock unlock request reception status] Indicates steering lock unlock request signal reception state.
      Display range: NG/OK (10 s)      		 NG: Signal reception without IG ON, ACC ON, or engine start operation (10s): Within 10 seconds after IG ON, ACC ON or engine start operation
      • The engine cannot be started when the unlock request signal cannot be received.
      • If "OK" is not displayed even if the steering unlock conditions are satisfied, there may be a smart key computer assembly (Collation ECM) malfunction.

      Criteria: An unlock request signal is received within 10 seconds after the engine is started.

      NG: Replace the ID code box (immobilizer ECM)

      OK: Complete (Smart key computer assembly (Collation ECM) fault)

  10. Inspect the wiring harness and connector (Smart key computer assembly (Collation ECM) - Steering lock actuator assembly (Steering lock ECM)).
    1. Disconnect the steering lock actuator (Steering lock ECM) connector D59.
    2. Disconnect the smart key computer assembly (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.

      Resistance

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

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  11. Replacement of the steering lock actuator assembly (Steering lock ECM)
    1. Replace the steering lock actuator (Steering lock ECM) with a new part. (Refer to DISASSEMBLY  )
    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.

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

      OK: Complete (Failure of the steering lock actuator assembly)

  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 SSM3 to perform smart key computer assembly (Collation ECM) data monitoring.

      SSM3 screen: [Each System Check] →[Keyless Access System] →[Collation ECM] →[Current Data Display & Save]

      ITEM DESCRIPTION

      Item name Description/display range Normal value Remarks
      [S Code Check] Verification results between the collation ECM (smart key ECM assembly) and the ID code box (immobilizer code ECM)/OK or NG. OK: Confirmation results normal NG: Confirmation results abnormal If abnormal:
      • The ID code box (immobilizer code ECM) or the collation ECM (smart key ECM assembly) 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".

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

      OK: 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 SSM3 to perform smart key computer assembly (Collation ECM) data monitoring.

      SSM3 screen: [Each System Check] →[Keyless Access System] →[Collation ECM] →[Current Data Display & Save]

      ITEM DESCRIPTION

      Item name Description/display range Normal value Remarks
      [L Code Check] Display range indicating the collation results between the smart key computer assembly (Collation ECM) and the steering lock actuator assembly (Steering lock ECM). abnormal/normal Abnormal: Collation results abnormal: Collation results normal
      • The smart key computer assembly (Collation ECM) and the steering lock actuator assembly (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".

      NG: Replace the steering lock actuator assembly (Steering lock ECM) (Refer to DISASSEMBLY  )

      OK: Complete (ID code box (immobilizer ECM) fault)

  14. Replacement of the smart key computer assembly (Collation ECM)
    1. Replace the smart key computer assembly (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 SSM3 to perform smart key computer assembly (Collation ECM) data monitoring.

      SSM3 screen: [Each System Check] →[Keyless Access System] →[Collation ECM] →[Current Data Display & Save]

      ITEM DESCRIPTION

      Item name Description/display range Normal value Remarks
      [L Code Check] Display range indicating the collation results between the smart key computer assembly (Collation ECM) and the steering lock actuator assembly (Steering lock ECM). abnormal/normal Abnormal: Collation results abnormal: Collation results normal
      • The smart key computer assembly (Collation ECM) and the steering lock actuator assembly (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".

      NG: Replace the ID code box (immobilizer ECM)

      OK: Complete (Smart key computer assembly (Collation ECM) fault)

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