INSPECTION PROCEDURE 1: Communication with the M.U.T.-III is not possible.




COMMENTS ON TROUBLE SYMPTOM


If communication with all other systems is not possible, there is a high possibility that there is a malfunction of the diagnosis line. If only the A/C system can not communicate with the M.U.T.-III, the A/C-ECU may be defective.

PROBABLE CAUSE


Malfunction of the A/C-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?

Check and repair the power supply circuit system.
Repair the CAN bus line (Refer to GROUP 54C, Troubleshooting ).