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

1. Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC. Refer to CHECK FOR INTERMITTENT PROBLEMS .
   MOMENTARY INTERRUPTION CHECK
   
   

   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.

C → See step   4 

B → See step   3 

A: Go to next step 

1. Turn the engine 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: Go to next step 

1. Turn the engine switch off.
2. 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

C → See step   8 

B → See step   7 

A → See step   6 

1. Turn the engine 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. Refer to CHECK FOR INTERMITTENT PROBLEMS .
4. Check that there are no momentary interruptions.

NEXT: Go to next step 

1. Turn the engine switch off.
2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
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. Refer to DIAGNOSIS SYSTEM .
6. 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).

C → See step   8 

B → See step   7 

A → END