Code No.U0404: Abnormality in AS&G signal


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 - CAN Bus Diagnostics Table .).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.
  • 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.

OPERATION



DIAGNOSIS CODE SET CONDITION



PROBABLE CAUSES



  • Wiring harness or connector failure of CAN bus line
  • AS&G-ECU malfunction
  • ASC-ECU malfunction

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
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 Diagnostics Table .). On completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines

Q. Is diagnosis code No.U0404 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. ETACS-ECU coding data check
Refer to GROUP 00 - Coding List .

Q. Is the check result normal?
Go to Step 4.
Replace the ETACS-ECU (Refer to GROUP 54A - ETACS-ECU .), and then go to Step 6.

STEP 4. M.U.T.-III other system diagnosis code
Use M.U.T.-III to check whether any diagnosis code related to vehicles information is set or not by the AS&G-ECU.

Q. Is the diagnosis code set?
Troubleshoot for the relevant diagnosis code, and then go to Step 5.
Go to Step 5.

STEP 5. Check whether the diagnosis code is reset.
Erase the diagnosis code.

Q. Is diagnosis code No.U0404 set?
Replace the hydraulic unit (integrated with ASC-ECU) (Refer to .), and then go to Step 6.
This diagnosis is complete.

STEP 6. Check whether the diagnosis code is reset.
Erase the diagnosis code.

Q. Is diagnosis code No.U0404 set?
Return to Step 1.
This diagnosis is complete.