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Home >> Toyota >> 2017 >> Corolla L >> Repair and Diagnosis (Single Page) >> Transmission >> Automatic Trans >> Continuously Variable Transaxle - Diagnostic Codes (3 Of 3) & Circuit Tests (Model Code: ZRE172) >> Continuously Variable Transaxle System >> DTC U0129: Lost Communication with Brake System Control Module [08/2016 - ] >> Procedure
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DTC U0129: Lost Communication with Brake System Control Module [08/2016 - ]: Procedure

  1. CLEAR DTC AND PERFORM ROAD TEST 
    1. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs 

      HINT: 

      Write down the currently output DTCs before clearing them.

    2. Start the engine and drive the vehicle at a low speed.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    See step  2

  2. CHECK DTC OUTPUT (DTC U0129) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

      Powertrain > Engine and ECT > Trouble Codes 

    5. Read the DTCs using the Techstream.

      Result

      Result Proceed to
      DTC U0129 is not output A
      DTC U0129 is output B

    Result:  1

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [08/2013 - ] 

    Result:  2

    GO TO CAN COMMUNICATION SYSTEM 

    w/o Central Gateway ECU: Refer to DIAGNOSIS SYSTEM [08/2016 - 08/2017] , DIAGNOSIS SYSTEM [08/2017 - ]

    w/ Central Gateway ECU: Refer to DIAGNOSIS SYSTEM [08/2016 - ]