Climate Control
DTC B1235 or DTC indicator K and AUTO: A Problem in the Driver's Air Mix Control Linkage, Door, or Motor1. Clear the DTC by turning the ignition switch to LOCK (0), and then turn to ON (II).
2. Operate the climate control system in several modes.
3. Check for DTCs using the HDS or self-diagnostic.
Is DTC B1235 or K and AUTO indicated?
YES - Go to step 4.
NO - Intermittent failure.
4. Turn the ignition switch to LOCK (0).
5. Test the driver's air mix control motor.
Is the driver's air mix control motor OK?
YES - Go to step 6.
NO - Replace the driver's air mix control motor, or repair the driver's air mix control linkage or door.
6. Disconnect the driver's air mix control motor 7P connector.
7. Disconnect the front climate control unit 30P connector.
8. Check for continuity between the following terminals of the front climate control unit 30P connector and the driver's air mix control motor 7P connector.
Is there continuity?
YES - Go to step 9.
NO - Repair open in the wire(s) between the front climate control unit and the driver's air mix control motor.
9. Check for continuity between body ground and the front climate control unit 30P connector No. 10 and No. 11 terminals individually.
Is there continuity?
YES - Repair short to body ground in the wire(s) between the front climate control unit and the driver's air mix control motor.
NO - Substitute a known-good front climate control unit, and recheck. If the symptom/indication goes away, replace the original front climate control unit.