B1240
DTC B1240 or DTC indicator M: A Problem in the Mode Control Linkage, Doors, or Motor1. Clear the DTC.
2. Turn the ignition switch OFF, and then ON (II).
3. Operate the climate control system in several modes.
4. Check the DTCs.
Is DTC B1240 or M indicated?
YES - Go to step 5.
NO - Intermittent failure.
5. Turn the ignition switch OFF.
6. Test the mode control motor.
Are the mode control motor and linkage OK?
YES - Go to step 7.
NO - Replace the mode control motor, or repair the mode control linkage or doors.
7. Disconnect mode control motor 7P connector.
8. Disconnect climate control unit connector A (22P).
9. Check for continuity between the following terminals of audio-HVAC display panel connector A (22P) and mode control motor 7P connector.
Is there continuity?
YES - Go to step 10.
NO - Repair open in the wire(s) between the audio-HVAC display panel and the mode control motor.
10. Check for continuity between body ground and audio-HVAC display panel connector A (22P) terminals No. 6 and No. 7 individually.
Is there continuity?
YES - Repair short to body ground in the wire(s) between the audio-HVAC display panel and the mode control motor.
NO - Substitute a known-good audio-HVAC display panel, and recheck. If the symptom/indication goes away, replace the original audio-HVAC display panel.