Code No.C1396: Engine-ECU malfunction


caution If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Diagnose the CAN bus lines before the diagnosis codes (Refer to GROUP 54C - CAN Bus Diagnostics Table ).

OPERATION
The hydraulic unit (integrated with ASTC-ECU) communicates with the engine-ECU via the CAN bus line. ASTC-ECU sends the command to the engine-ECU to reduce the engine power at the ASC or ATC operation.

DIAGNOSIS CODE SET CONDITION
This diagnosis code is set when the ASTC-ECU power supply voltage is normal but the engine-ECU is abnormal after the engine is started.

PROBABLE CAUSES
The most likely causes for this diagnosis code to set are:

  • Malfunction of the engine-ECU
  • Damaged wiring harness or connector
  • Malfunction of the hydraulic unit assembly (integrated with ASTC-ECU)

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 2.
Repair the CAN bus line (Refer to GROUP 54C - CAN Bus Diagnostics Table ). Then go to Step 2.

STEP 2. Check whether the diagnosis code is reset.
(1)Turn the ignition switch to the "ON" position.
(2)Erase the diagnosis code.
(3)Turn the ignition switch to the "LOCK" (OFF) position.
(4)Turn the ignition switch to the "ON" position.
(5)Check if the diagnosis code is set.
(6)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is code No.C1396 set?
Check if a diagnosis code is set by the engine-ECU. (Refer to 13A - Inspection Chart for Diagnosis Codes .)Then go to Step 3.
The procedure is complete.

STEP 3. Check whether the diagnosis code is reset.
(1)Turn the ignition switch to the "ON" position.
(2)Erase the diagnosis code.
(3)Turn the ignition switch to the "LOCK" (OFF) position.
(4)Turn the ignition switch to the "ON" position.
(5)Check if the diagnosis code is set.
(6)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is code No.C1396 set?
Replace the hydraulic unit (integrated with ASTC-ECU) (Refer to ). Then go to Step 4.
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunctions ).

STEP 4. Check whether the diagnosis code is reset.
(1)Turn the ignition switch to the "ON" position.
(2)Erase the diagnosis code.
(3)Turn the ignition switch to the "LOCK" (OFF) position.
(4)Turn the ignition switch to the "ON" position.
(5)Check if the diagnosis code is set.
(6)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is code No.C1396 set?
Go to Step 1.
The procedure is complete.