VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:U0073, U0100, U0124, U0126

DTC Code DTC Name
U0073 Control Module Communication Bus OFF
U0100 Lost Communication with ECM / PCM
U0124 Lost Communication with Lateral Acceleration Sensor Module
U0126 Lost Communication with Steering Angle Sensor Module

DESCRIPTION

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

DTC No. DTC Detection Condition Trouble Area
U0073

Either of the following is detected:


  1. A bus OFF state occurs once or more within 0.1 seconds, 10 times in succession. (Sent signals cannot be received.)

  2. When the +BS 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.

  3. When the +BS terminal voltage is between 10 and 17.4 V, the following occurs 10 times in succession within 60 seconds.


    • 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 +BS terminal voltage is between 10 and 17.4 V, and the vehicle speed is 15 km/h (9 mph) or more, data cannot be received from the ECM for 2 seconds or more.

  • CAN communication system

  • Skid control ECU (Brake actuator assembly)

  • ECM
U0124

Either of the following is detected:


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

  2. When the +BS terminal voltage is between 10 and 17.4 V, the following occurs 10 times in succession within 60 seconds.


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

  • CAN communication system

  • Skid control ECU (Brake actuator assembly)

  • Acceleration sensor (Airbag sensor assembly)
U0126

Either of the following is detected:


  1. When the +BS 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 +BS 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

  • Skid control ECU (Brake actuator assembly)

  • Steering angle sensor (Spiral with sensor cable sub-assembly)

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)


    1. Using the GTS, 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 ECM communication open detection / Error or Normal Normal Error: Momentary interruption
      Yaw Rate Open Yaw rate sensor open detection / Error or Normal Normal Error: Momentary interruption
      Deceleration Open Acceleration sensor open detection / Error or Normal Normal Error: Momentary interruption
      Steering Open Steering angle sensor open detection / Error or Normal Normal Error: Momentary interruption
      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 VSC system and/or CAN communication system) Click here for VSC system, or Click here for CAN communication system).

      Tech Tips

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

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

    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    USE SIMULATION METHOD TO CHECK Click here

    A

    CHECK CAN COMMUNICATION SYSTEM 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 DTCs Click here.

    3. Turn the ignition switch off.

    4. Start the engine.

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

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

    7. If VSC system DTCs are output, record them Click here.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (relating to 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 VSC system).


    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    CHECK CAN COMMUNICATION SYSTEM Click here

    A

    END