Code No.U0431: ETACS CAN data abnormal


caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be stored. Prior to this diagnosis, diagnose the CAN bus lines.
  • Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
  • When the ETACS-ECU is replaced, chassis number writing and coding must be performed. If the ETACS-ECU stores diagnosis code No. B1761 "VIN not registered" or No. B222C "Coding imcomplete", you must write the correct VIN to the ECU and then code the ECU. Refer to the "M.U.T.-III operation manual" and perform coding. (Refer to GROUP 54A - ETACS-ECU .)

OPERATION


4WD-ECU communicates with the ETACS-ECU via the CAN bus lines.

DIAGNOSIS CODE SET CONDITION


This diagnosis code will be stored when the ETACS-ECU sends an abnormal signal.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics.
Use M.U.T.-III to perform the CAN bus diagnosis.

Q. Is the check result normal?
Go to Step 2
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting ). Then go to Step 6.

STEP 2. M.U.T.-III diagnosis code.
Check if diagnosis code No.U1195 is stored (Refer to ).

Q. Is the diagnosis code stored?
Perform the relevant troubleshooting.
Go to Step 3

STEP 3. M.U.T.-III other system diagnosis code.
Check the ETACS diagnosis code (Refer to GROUP 54A - Troubleshooting ).

Q. Is the diagnosis code stored?
Perform the relevant troubleshooting.
Go to Step 4

STEP 4. M.U.T.-III data list.
Check the ETACS data list below (Refer to GROUP 54A - ETACS ).

  • Item No.252: Ambient temperature sensor
  • Item No.254: IG voltage

Q. Is the check result normal?
Go to Step 5
Replace the ETACS-ECU. (Refer to GROUP 54A - ETACS-ECU .) Then go to Step 5.

STEP 5. Check whether the diagnosis code is stored again.

Q. Is diagnosis code No.U0431 stored?
Replace the 4WD-ECU (Refer to ). Then go to Step 6.
Intermittent malfunction. (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

STEP 6. Check whether the diagnosis code is stored again.

Q. Is diagnosis code No.U0431 stored?
Return to Step 1.
This diagnosis is complete.