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DTC B2285: Steering Lock Position Signal Circuit Malfunction [11/2019 - 10/2022]: Procedure

  1. CHECK FOR DTC 
    1. Check for DTCs.

      Body Electrical > Smart Access > Trouble Codes 

      HINT: 

      • If the steering cannot be unlocked, the engine switch cannot be turned on (IG) and the engine cannot be started.
      • If LIN communication is not available, the steering cannot be locked or unlocked.

      OK

      LIN communication system DTC B2785 is not output simultaneously.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO DTC B2785. Refer to  DTC B2785: Communication Malfunction between ECUs Connected by LIN [09/2014 - 10/2022] 

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (STEERING UNLOCK SWITCH) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Power Source Control / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Power Source Control > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Steering Unlock Switch State of steering unlock sensor signal output from steering lock ECU (steering lock actuator assembly) OFF or ON OFF: Steering locked
      ON: Steering unlocked
      • When the shift lever is in P and the engine switch is off, if any door is opened or closed, the steering is locked.
      • When the electrical key transmitter sub-assembly is in the cabin and the engine switch is turned on (ACC) or on (IG), the steering unlocks.
      • The engine cannot be started when the steering unlock signal is off.

      Body Electrical > Power Source Control > Data List 

      Tester Display
      Steering Unlock Switch

      Result

      Result Proceed to
      Techstream display does not change A
      Techstream display changes B

    Result: 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - ] 

    Result: 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 

    See step  1

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (GROUND) 

    See step  2

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CONFIRM MODEL 
    1. Choose the model to be inspected.

      Result

      Result Proceed to
      except Lexus Enform Remote Compatible Type A
      for Lexus Enform Remote Compatible Type B

    Result: 

    See step  8

    Result: 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Disconnect the O6 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O6-23 (SLP) - O27-4 (SLP1) Always Below 1 Ω
      O6-23 (SLP) or O27-4 (SLP1) - Body ground Always 10 kΩ or higher
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      O6-23 (SLP) or O27-4 (SLP1) - Body ground Always Below 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    2. Reconnect the O6 certification ECU (smart key ECU assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY500754Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-4 (SLP1) - Body ground Positive (+) tester probe → O27-4 (SLP1)
      Negative (-) tester probe → Body ground
      Steering locked → unlocked* 10 kΩ or higher → Below 1 Ω

      HINT: 

      • *: If any of the doors are opened with the shift lever in P and the engine switch off, the steering will be locked. If the engine switch is turned on (ACC) or on (IG) with the electrical key transmitter sub-assembly in the cabin, the steering will be unlocked.
      • DTC B2285 may be stored due to a malfunction in the steering lock ECU (steering lock actuator assembly). The steering lock position signal and unlock position signal are sent from the steering lock ECU (steering lock actuator assembly) to the certification ECU (smart key ECU assembly) individually.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ] 

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - ] 

  8. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY - DCM) 
    1. Disconnect the O6 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    3. Disconnect the O204 DCM (telematics transceiver) connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O6-23 (SLP) - O27-4 (SLP1) Always Below 1 Ω
      O27-4 (SLP1) - O204-30 (SLPD) Always Below 1 Ω
      O6-23 (SLP) or O27-4 (SLP1) or O204-30 (SLPD) - Body ground Always 10 kΩ or higher
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      O6-23 (SLP) or O27-4 (SLP1) or O204-30 (SLPD) - Body ground Steering locked 11 to 14 V
      Steering unlocked Below 1.5 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    2. Reconnect the O6 certification ECU (smart key ECU assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.
      GTY500752Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-4 (SLP1) - Body ground Positive (+) tester probe → O27-4 (SLP1)
      Negative (-) tester probe → Body ground
      Steering locked → unlocked* 10 kΩ or higher → Below 1 Ω

      HINT: 

      • *: If any of the doors are opened with the shift lever in P and the engine switch off, the steering will be locked. If the engine switch is turned on (ACC) or on (IG) with the electrical key transmitter sub-assembly in the cabin, the steering will be unlocked.
      • DTC B2285 may be stored due to a malfunction in the steering lock ECU (steering lock actuator assembly). The steering lock position signal and unlock position signal are sent from the steering lock ECU (steering lock actuator assembly) to the certification ECU (smart key ECU assembly) individually.
      • Measure the resistance with the certification ECU (smart key ECU assembly) and steering lock ECU (steering lock actuator assembly) connectors connected.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - ] 

    Result: 

    OK 

    See step  10

  10. INSPECT SMART KEY ECU ASSEMBLY 
    1. Disconnect the O204 DCM (telematics transceiver) connector.
    2. Check the push-button start function.
      1. Enter the vehicle while carrying an electrical key transmitter sub-assembly.
      2. Depress the brake pedal with the shift lever in P.
      3. Check that the engine starts when the engine switch is pressed.

      Result

      Result Proceed to
      Engine starts A
      Engine does not start B

    Result: 

    REPLACE DCM (TELEMATICS TRANSCEIVER) 

    Result: 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ]