Code No. C1394 Steering wheel sensor neutral point not learned


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.

OPERATION
The steering wheel sensor output signal is sent to ASC-ECU via the CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS
ASC-ECU receives information of the steering wheel sensor calibration from the steering wheel sensor. When this information indicates that the calibration is not performed, the ECU sets the diagnosis code.

PROBABLE CAUSES

  • Steering wheel sensor calibration not implemented
  • Malfunction of ASC-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the 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 the diagnosis code No.C1394 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. M.U.T.-III data list
Check the following data list (Refer to ).

  • Item No. 30: SAS calibration flag

Q. Is the check result normal?
Go to Step 4.
Perform calibration of steering wheel sensor (Refer to ). Then go to Step 4.

STEP 4. Diagnosis code recheck
(1)Erase the diagnosis code.
(2)Turn the electric motor switch from "LOCK" (OFF) position to "ON" position.

Q. Is the diagnosis code No.C1394 set?
Replace the hydraulic unit (integrated with ASC-ECU) (Refer to ). Then go to Step 5.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).

STEP 5. Diagnosis code recheck
(1)Erase the diagnosis code.
(2)Turn the electric motor switch from "LOCK" (OFF) position to "ON" position.

Q. Is the diagnosis code No.C1394 set?
Return to Step 1.
This diagnosis is complete.