VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:U0073, U0100, U0123, U0124, 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
U0124 Lost Communication with Lateral Acceleration Sensor Module
U0126 Lost Communication with Steering Angle Sensor Module

DESCRIPTION

The skid control ECU receives the signals from the ECM, steering angle sensor, and yaw rate and acceleration sensor via the CAN communication system.

DTC Code 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 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 and acceleration 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 and acceleration sensor and steering angle sensor occurs more than once within 5 seconds.

 CAN communication system
U0100

When either of the following is detected:


  1. 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 sent to the ECM for 2 seconds or more.

  2. 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

(Skid control ECU to ECM)
U0123

When either of the following is detected:


  1. When the IG1 terminal voltage is between 10 and 17.4 V, data from the yaw rate 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 yaw rate sensor cannot be received occurs once or more within 5 seconds.

CAN communication system

(Skid control ECU to yaw rate and acceleration sensor)
U0124

When either of the following is detected:


  1. When the IG1 terminal voltage is between 10 and 17.4 V, 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 acceleration sensor cannot be received occurs once or more within 5 seconds.

CAN communication system

(Skid control ECU to yaw rate and acceleration sensor)
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

(Skid control ECU to steering angle sensor)

INSPECTION PROCEDURE

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

      		 -
      Result
      Result Proceed to
      There are momentary interruptions A
      There are no momentary interruptions B
      There is a constant open circuit 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 output (relating to CAN communication system) A
      DTC output (relating to ABS and/or VSC system) B
      DTC not output C

    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) 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 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 output (relating to CAN communication system) A
      DTC output (relating to ABS and/or VSC system) B
      DTC not output C

      Tech Tips

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


    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    C

    END

    A

    CHECK CAN COMMUNICATION SYSTEM Click here