DTC P
DTC B1240 or DTC indicator P: A Problem in the Mode Control Linkage, Doors, or Motor1. Clear the DTC with the HDS.
2. Operate the climate control system in several modes.
3. Check for DTCs using the HDS or self-diagnostic.
Is DTC B1240 or P indicated?
YES - Go to step 4.
NO - Intermittent failure, check for loose wires or poor connections on the mode control motor circuit.
4. Turn the ignition switch OFF.
5. Test the mode control motor.
Is the mode control motor OK?
YES - Go to step 6.
NO - Replace the mode control motor, or repair the mode control linkage or doors.
6. Disconnect the front mode control motor 7P connector.
7. Disconnect the climate control unit 30P connector.
8. Check for continuity between the following terminals of climate control unit 30P connector and the front mode control motor 7P connector.
Is there continuity?
YES - Go to step 9.
NO - Repair open in the wire(s) between the climate control unit and the mode control motor.
9. Check for continuity between body ground and climate control unit 30P connector No. 18 and No. 19 terminals 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.