VEHICLE STABILITY CONTROL SYSTEM(for TMC Made), Diagnostic DTC:U0073, U0100, U0124, U0126, U0142

DTC Code DTC Name
U0073 Control Module Communication Bus OFF
U0100 Lost Communication with ECM
U0124 Lost Communication with Lateral Acceleration Sensor Module
U0126 Lost Communication with Steering Angle Sensor Module
U0142 Lost Communication with Main Body ECU

DESCRIPTION

The skid control ECU (brake actuator assembly) receives the signals from the ECM, steering angle sensor (spiral cable sub-assembly), and yaw rate sensor (airbag sensor assembly) via the CAN communication system.

DTC No. DTC Detection Condition Trouble Area
U0073

When any of the following is detected:


  1. When the IG1 terminal voltage is between 10 and 17.4 V, after the output of data from the skid control ECU (brake actuator assembly) is completed, the sending continues for 5 seconds or more.

  2. The condition that bus OFF state occurs once or more within 0.1 seconds occurs 10 times in succession. (Sent signals cannot be received.)

  3. When the IG1 terminal voltage is between 10 and 17.4 V, a delay in receiving data from the yaw rate sensor and steering angle sensor continues for 1 second or more.

  4. When the IG1 terminal voltage is between 10 and 17.4 V, the following occurs 10 times in succession.


    • The condition that a delay in receiving data from the yaw rate sensor and steering angle sensor occurs more than once within 5 seconds.

 CAN communication system
U0100 When the IG1 terminal voltage is between 10 and 17.4 V, and the vehicle speed 15 km/h (9 mph) or more, data cannot be received to the ECM for 2 seconds or more. CAN communication system
U0124

When either of the following is detected:


  1. When the IG1 terminal voltage is between 10 and 17.4 V, and the vehicle speed 7 km/h or more, data from the acceleration sensor cannot be received for 1 second or more.

  2. When the IG1 terminal voltage is between 10 and 17.4 V, the following occurs 10 times in succession.


    • The condition that data from the deceleration sensor cannot be received occurs once or more within 5 seconds.

 CAN communication system
U0126

When either of the following is detected:


  1. When the IG1 terminal voltage is between 10 and 17.4 V, data from the steering angle sensor cannot be received for 1 second or more.

  2. When the IG1 terminal voltage is between 10 and 17.4 V, the following occurs 10 times in succession.


    • The condition that data from the steering angle sensor cannot be received occurs once or more within 5 seconds.

 CAN communication system
U0142 No communication with main body ECU

CAN communication system

Main body ECU

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)


    1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to a DTC Click here.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      EFI Communication Open EFI communication open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      Yaw Rate Open Yaw rate sensor open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      Steering Open Steering sensor open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      Body ECU Communication Open Body ECU open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      Result
      Result Proceed to
      There is a constant open circuit A
      There are no momentary interruptions B
      There are momentary interruptions C

      Tech Tips

      Perform the above inspection before removing the sensor and connector.


    B

    RECONFIRM DTC Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    A

  2. CHECK IF EACH SENSOR AND ECM CONNECTOR IS SECURELY CONNECTED


    1. Turn the ignition switch off.

    2. Check if each sensor or ECM connector is securely connected.

      OK
      Each connector is securely connected.

    NG

    CONNECT CONNECTOR TO EACH SENSOR OR ECM CORRECTLY

    OK

  3. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Record the output DTCs (for ABS, VSC, and CAN communication) Click here.

      Tech Tips

      If the CAN communication system DTC and the relevant sensor DTCs are output simultaneously, troubleshoot the relevant sensor DTCs (for ABS and VSC) after the CAN communication system returns to normal.

      Result
      Result Proceed to
      DTC (relating to CAN communication system) is output A
      DTC (relating to ABS and/or VSC system) is output B
      DTC is not output C

    A

    CHECK CAN COMMUNICATION SYSTEM Click here

    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Turn the ignition switch off.

    2. Repair or replace the harness or connector.

    3. Check for any momentary interruption between the skid control ECU (brake actuator assembly) and each sensor or ECM Click here.

    4. Check that there is no momentary interruption.


    NEXT

  5. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTC Click here.

    3. Start the engine.

    4. Drive the vehicle and turn the steering wheel to the right and left at a speed of 15 km/h (9 mph) or more.

    5. Check that no CAN communication system DTC is output Click here.

    6. If ABS and VSC DTCs are output, record them.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (relating to ABS and/or VSC system) B
      DTC is output (relating to CAN communication system) C

      Tech Tips

      The CAN communication system must be normal when repairing each sensor DTC (for ABS and VSC).


    A

    END

    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    CHECK CAN COMMUNICATION SYSTEM Click here