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Home >> Lexus >> 2020 >> LS 500 Base, AWD >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> Seat Belt System - Diagnostic Codes & Circuit Tests >> Seat Belt System >> DTC U0075-88: Control Module Communication Bus "C" Off Bus Off; DTC U0129-87: Lost Communication With Brake System Control Module Missing Message; DTC U0140-87: Lost Communication with Body Control Module Missing Message; DTC U0151-87: Lost Communication with Restraints Control Module Missing Message; DTC U1104-87: Lost Communication with Driving Support ECU Missing Message [12/2017 - 10/2020] >> Procedure
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DTC U0075-88: Control Module Communication Bus "C" Off Bus Off; DTC U0129-87: Lost Communication With Brake System Control Module Missing Message; DTC U0140-87: Lost Communication with Body Control Module Missing Message; DTC U0151-87: Lost Communication with Restraints Control Module Missing Message; DTC U1104-87: Lost Communication with Driving Support ECU Missing Message [12/2017 - 10/2020]: Procedure

  1. CLEAR DTCS 
    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 / Seat Belt Control / Clear DTCs.

      Body Electrical > Seat Belt Control > Clear DTCs 

    5. Check for DTCs by following the prompts on the Techstream screen.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. CHECK FOR DTC 
    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 / Seat Belt Control / Trouble Codes.
    5. Check for DTCs and note any DTCs that are output.

      Body Electrical > Seat Belt Control > Trouble Codes 

      OK

      DTC U0075-88, U0129-87, U0140-87 U0151-87 and U1104-87 are not output

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 09/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2018 - 10/2020] 

    Result: 

    NG 

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING). Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 09/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2018 - 10/2020]