Inspection Procedure 1

INSPECTION PROCEDURE 1: Communication between scan tool and AWC-ECU cannot be established

CAUTION:

- If there is any problem in the CAN bus lines, an incorrect trouble symptom may occur. Prior to this diagnosis, always diagnose the CAN bus lines.

- Whenever the ECU is replaced, ensure that the CAN bus lines are normal.

SYMPTOMS

CAN bus line, AWC-ECU power supply circuit, or AWC-ECU may have a problem.

PROBABLE CAUSES

- Wrong M.U.T.-III wiring harness

- The CAN bus line is defective.

- AWC-ECU power supply circuit malfunction

- Malfunction of AWC-ECU

- ECU malfunction of other system

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics.

Use scan tool to perform the CAN bus diagnosis.

Q. Is the check result normal?

YES Check/repair the AWC-ECU power supply circuit. (Refer to Inspection Procedure 2.)
NO Repair the CAN bus lines. CAN Bus Diagnostics Chart).