Code No. U1003 G and yaw rate sensor bus-off












caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C, Trouble code diagnosis ).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.
  • Do not drop or shock the G and yaw rate sensor.
  • When the G and yaw rate sensor is replaced, always carry out calibration to make ASC-ECU learn the neutral point (Refer to ).
  • When the hydraulic unit (integrated with ASC-ECU) is replaced, always carry out the calibration of the steering wheel sensor, the G and yaw rate sensor and brake fluid pressure sensor (Refer to , and ).

OPERATION
The G and yaw rate sensor outputs the signal to ASC-ECU via the special CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS
This diagnosis code is set when ASC-ECU cannot receive the signal sent from the G and yaw rate sensor.

PROBABLE CAUSES

  • Wiring harness or connector failure for the special CAN bus lines between ASC-ECU and the G and yaw rate sensor
  • G and yaw rate sensor malfunction
  • ASC-ECU malfunction

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnosis
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnosis table ). On completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines

Q. Is the diagnosis code No.U0125 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. Connector check: A-03 ASC-ECU connector, C-30 G and yaw rate sensor connector

Q. Is the check result normal?
Go to Step 4.
Repair the connector, and then go to Step 5.

STEP 4. Wiring harness check between A-03 ASC-ECU connector terminals No.29 and C-30 G and yaw rate sensor connector terminals No.2, and between A-03 ASC-ECU connector terminals No.25 and C-30 G and yaw rate sensor connector terminals No.3.

  • Check for open circuit in communication circuit

Q. Is the check result normal?
Go to Step 5.
Repair the wiring harness, and then go to Step 5.

STEP 5. Check whether the diagnosis code is reset.

Q. Is the diagnosis code No.U0125 set?
Replace the G and yaw rate sensor (Refer to ), and then go to Step 6.
This diagnosis is complete.

STEP 6. Check whether the diagnosis code is reset.

Q. Is the diagnosis code No.U0125 set?
Replace the ASC-ECU (Refer to ), and then go to Step 7.
This diagnosis is complete.

STEP 7. Check whether the diagnosis code is reset.

Q. Is the diagnosis code No.U0125 set?
Return to Step 1.
This diagnosis is complete.