B1240

DTC B1240 or DTC indicator B: A Problem in the Front Mode Control Linkage, Doors, or Motor Circuit

1. Clear the DTC with the HDS.
2. Turn the ignition switch to LOCK (0), and then ON (II).
3. Do the self-diagnostic with the HDS or climate control unit.
4. Check for DTCs.

Is DTC B1240 or B indicated?

YES - Go to step 5.

NO - Intermittent failure, check for loose wires or poor connections on the mode control motor circuit.

5. Turn the ignition switch to LOCK (0).
6. Test the front mode control motor.

Is the front mode control motor OK?

YES - Go to step 7.

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

7. Disconnect the front mode control motor 7P connector.
8. Disconnect climate control unit connector A (40P).
9. Check for continuity between the following terminals of climate control unit connector A (40P) and the front mode control motor 7P connector.






Is there continuity?

YES - Go to step 10.

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

10. Check for continuity between body ground and climate control unit connector A (40P) No. 16 and No. 17 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.