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DTC B2285: Steering Lock Position Signal Circuit Malfunction [07/2015 - ]: Procedure

  1. CHECK FOR DTC (LIN COMMUNICATION SYSTEM) 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR [07/2015 - ]

      OK

      LIN communication system DTC B2785 is not output simultaneously.

      HINT: 

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

    Result:  NG

    NG 

    GO TO DTC B2785 

    Refer to DTC B2785: Communication Malfunction between ECUs Connected by LIN [07/2015 - ]

    Result:  OK

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power 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.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Steering Unlock Switch State of steering unlock sensor signal output from steering lock actuator assembly/ON or OFF ON: Steering unlocked
      OFF: Steering locked
      • When the shift lever is in P and the power 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 power switch is turned on (ACC) or on (IG), the steering unlocks.
      • The hybrid control system cannot be started when the steering unlock sensor signal is OFF.

      Result

      Result Proceed to
      Data List display does not change A
      Data List display changes B

    Result:  B

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    Refer to DISASSEMBLY [07/2015 - ]

    Result:  A

    See step  3

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 

    See step  1

    Result:  NG

    NG 

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

    Result:  OK

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (GROUND) 

    See step  2

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    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:  B

    See step  8

    Result:  A

    See step  6

  6. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Disconnect the H57 certification ECU (Smart key ECU assembly) connector.
    2. Disconnect the H18 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
      H57-26 (SLP) - H18-4 (SLP1) Always Below 1 Ω
      H57-26 (SLP) or H18-4 (SLP1) - Body ground Always 10 kΩ or higher

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  7

  7. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Measure the resistance according to the value(s) in the table below.
      GTY638890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      Positive (+) tester probe → H18-4 (SLP1)
      Negative (-) tester probe → Body ground
      Steering locked* 10 kΩ or higher
      Steering unlocked* Below 1 Ω

      HINT: 

      • *: If any of the doors are opened then closed with the shift lever in P and the power switch off, the steering will be locked. If the power switch is then turned on (ACC) or on (IG), 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.
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

    Result:  OK

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    Refer to REMOVAL [07/2015 - ]

    Result:  NG

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    Refer to DISASSEMBLY [07/2015 - ]

  8. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STEERING LOCK ECU - DCM) 
    1. Disconnect the H57 certification ECU (Smart key ECU assembly) connector.
    2. Disconnect the H18 steering lock ECU (steering lock actuator assembly) connector.
    3. Disconnect the H101 DCM (telematics transceiver) connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H57-26 (SLP) - H18-4 (SLP1) Always Below 1 Ω
      H18-4 (SLP1) - H101-29 (SLPD) Always Below 1 Ω
      H57-26 (SLP) or H18-4 (SLP1) or H101-29 (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
      H57-26 (SLP) or H18-4 (SLP1) or H101-29 (SLPD) - Body ground Always Below 1 V

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  9

  9. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Disconnect the H101 DCM (telematics transceiver) connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY678629Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      Positive (+) tester probe → H18-4 (SLP1)
      Negative (-) tester probe → Body ground
      Steering locked* 10 kΩ or higher
      Steering unlocked* Below 1 Ω

      HINT: 

      • *: If any of the doors are opened then closed with the shift lever in P and the power switch off, the steering will be locked. If the power switch is then turned on (ACC) or on (IG), 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.
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

    Result:  NG

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    Refer to DISASSEMBLY [07/2015 - ]

    Result:  OK

    OK 

    See step  10

  10. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Disconnect the H101 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 power switch is pressed.

      OK

      Engine starts.

      HINT: 

      Check the steering lock ECU (steering lock actuator assembly) and certification ECU (Smart key ECU assembly) connectors connected.

    Result:  OK

    OK 

    REPLACE DCM (TELEMATICS TRANSCEIVER) 

    Result:  NG

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    Refer to REMOVAL [07/2015 - ]