VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:U0073, U0100, U0123, U0126

DTC Code DTC Name
U0073 Control Module Communication Bus OFF
U0100 Lost Communication with ECM / PCM
U0123 Lost Communication with Yaw Rate Sensor Module
U0126 Lost Communication with Steering Angle Sensor Module

DESCRIPTION

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

DTC Code DTC Detection Condition Trouble Area
U0073 The +BS terminal voltage is between 9.6 and 16.5 V and a bus OFF state occurs for 0.1 seconds or more. CAN communication system
U0100 The +BS terminal voltage is between 9.6 and 16.5 V, the vehicle speed is 6 km/h (4 mph) or more, and signals cannot be sent to the ECM for 2.5 seconds or more.

  • CAN communication system

  • Skid control ECU (brake actuator assembly)

  • ECM
U0123 The +BS terminal voltage is between 9.6 and 16.5 V, the vehicle speed is 6 km/h (4 mph) or more, and signals from the yaw rate and acceleration sensor cannot be received for 1.1 seconds or more.

  • CAN communication system

  • Skid control ECU (brake actuator assembly)

  • Yaw rate sensor
U0126 The +BS terminal voltage is between 9.6 and 16.5 V, the vehicle speed is 6 km/h (4 mph) or more, and signals from the steering angle sensor cannot be received for 1.1 seconds or more.

  • CAN communication system

  • Skid control ECU (brake actuator assembly)

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

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 EFI communication open detection/ Error or Normal Normal: Normal Error: Momentary interruption
      Yaw Rate Open Yaw rate sensor open detection/ Error or Normal Normal: Normal Error: Momentary interruption
      Deceleration Open Acceleration sensor open detection / Error or Normal Normal: Normal Error: Momentary interruption
      Steering Open Steering angle sensor open detection/ Error or Normal Normal: Normal Error: Momentary interruption
      Result
      Result Proceed to
      There is a constant interruption. (Error is displayed without interruption.) A
      There are no momentary interruptions. B
      There are momentary interruptions. (Error is displayed intermittently.) C

      Tech Tips

      Perform the above inspection before disconnecting any sensors or connectors.


    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). (See page and Click here).

      Tech Tips

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

      Result
      Result Proceed to
      DTCs are not output. A
      DTCs are output. B
      CAN communication system DTCs are output. C

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    INSPECT 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 that there is no momentary interruption between the skid control ECU (brake actuator assembly) and each sensor or ECM Click here.


    NEXT

  5. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTCs Click here.

    3. Start the engine.

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

    5. Check that no CAN communication system DTCs are output Click here.

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

      Result
      Result Proceed to
      DTCs are not output. A
      DTCs are output. B
      CAN communication system DTCs are output. C

      Tech Tips

      The CAN communication system must be normal when performing troubleshooting for sensor DTCs (for VSC system).


    A

    END

    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    INSPECT CAN COMMUNICATION SYSTEM Click here