Operation CHARM: Car repair manuals for everyone.

DTC M

DTC indicator M: A Problem in the Front Mode Control Linkage, Doors, or Motor

1. Test the front mode control motor.

Is the front mode control motor OK?

YES - Go to step 2.

NO - Replace the front mode control motor, or repair the linkage and doors.

2. Disconnect the front mode control motor 7P connector.
3. Disconnect climate control unit connector B (30P).
4. Check for continuity between the following terminals of climate control unit connector B (30P) and the front mode control motor 7P connector.






Is there continuity?

YES - Go to step 5.

NO - Repair open in the wire(s) between the climate control unit and the front mode control motor.

5. Check for continuity between body ground and climate control unit connector B (30P) terminals No.8 and No.9 individually.






Is there continuity?

YES - Repair short to body ground in the wire(s) between the climate control unit and the front mode control motor.

NO - Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.