INSPECTION PROCEDURE 1: Communication with the MUT-II/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 MUT-II/III, the diagnosis line between the A/C-ECU and the diagnosis connector may be defective.POSSIBLE CAUSES
- Damaged the wiring harness or connectors
- Malfunction of the automatic air conditioner control panel (A/C-ECU)
DIAGNOSIS
STEP 2. Check operations of the air conditioner, defogger and outside/inside air selection damper control motor.
Q: Does the air conditioner, defogger or outside/inside air selection damper control motor operate?
YES:
Go to Step 3
.NO: Refer to Inspection procedure 10 "Malfunction of the A/C-ECU power supply system
."Step 4. Check the wiring harness between C-27 A/C-ECU connector (terminal 17 and 18) and C-18 diagnosis connector (terminal 11 and 1).
- Check the input and output lines for open or short circuit.
Q: Is the check result normal?
YES:
Replace the automatic air conditioner control panel (A/C-ECU)NO: Repair the wiring harness.