LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Scion >> 2016 >> iM Automatic CVT Trans >> Repair and Diagnosis (Single Page) >> Transmission >> Automatic Trans >> CVT System - Diagnostic Codes & Circuit Tests >> Continuously Variable Transaxle System >> DTC U0129: Lost Communication with Brake System Control Module [06/2015 - ] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC U0129: Lost Communication with Brake System Control Module [06/2015 - ]: Procedure

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

      Powertrain > Engine and ECT > Clear DTCs 

      HINT: 

      Write down any 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 [06/2015 - ] 

    Result:  2

    GO TO CAN COMMUNICATION SYSTEM. Refer to  DIAGNOSIS SYSTEM [06/2015 - ]