DTC U0073: Control Module Communication Bus OFF; DTC U0100: Lost Communication with ECM / PCM; DTC U0123: Lost Communication with Yaw Rate Sensor Module; DTC U0124: Lost Communication with Lateral Acceleration Sensor Module; DTC U0126: Lost Communication with Steering Angle Sensor Module: Procedure
- CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)
- Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC. Refer to CHECK FOR INTERMITTENT PROBLEMS
.ABS/VSC/TRAC
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 angle sensor 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 HINT:
Perform the above inspection before removing the sensor and connector.
B → See step 3
C → See step 4
A: Go to next step
- Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC. Refer to CHECK FOR INTERMITTENT PROBLEMS
.
- CHECK IF EACH SENSOR AND ECM CONNECTOR IS SECURELY CONNECTED
- Turn the engine switch off.
- 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: Go to next step
- RECONFIRM DTC
- Turn the engine switch off.
- Record the output DTCs (for ABS, VSC system and/or CAN communication system). Refer to DTC CHECK / CLEAR
for ABS and VSC system, or. Refer to DIAGNOSIS SYSTEM
for CAN communication system).
HINT:
If CAN communication system DTCs and the relevant sensor DTCs are output simultaneously, troubleshoot the relevant sensor DTCs (for ABS and/or VSC system) after the CAN communication system returns to normal.
Result
Result Proceed to DTC is not output A DTC (ABS and/or VSC system DTC) is output B DTC (CAN communication system DTC) is output C
B → See step 7
C → See step 6
A → See step 8
- REPAIR OR REPLACE HARNESS OR CONNECTOR
- Turn the engine switch off.
- Repair or replace the harness or connector.
- Check for any momentary interruption between the skid control ECU and each sensor or ECM. Refer to CHECK FOR INTERMITTENT PROBLEMS .
- Check that there are no momentary interruptions.
NEXT: Go to next step
- RECONFIRM DTC
- Turn the engine switch off.
- Clear the DTCs. Refer to DTC CHECK / CLEAR .
- Start the engine.
- Drive the vehicle and turn the steering wheel to the right and left at a speed of 15 km/h (9 mph) or more.
- Check that no CAN communication system DTC is output. Refer to DIAGNOSIS SYSTEM .
- If ABS and/or VSC system DTCs are output, record them.
Result
Result Proceed to DTC is not output A DTC (ABS and/or VSC system DTC) is output B DTC (CAN communication system DTC) is output C HINT:
The CAN communication system must be normal when performing troubleshooting for each sensor DTC (for ABS and/or VSC system).
B → See step 7
C → See step 6
A → END
- INSPECT CAN COMMUNICATION SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING
- REPAIR CIRCUIT INDICATED BY OUTPUT DTC. Refer to DIAGNOSTIC TROUBLE CODE CHART
- CHECK FOR INTERMITTENT PROBLEMS. Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE