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 heater or A/C system can not communicate with the M.U.T.-III, the heater control panel or A/C control panel may be defective.

PROBABLE CAUSE


Malfunction of the heater control panel or A/C control panel

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 ).