Operation CHARM: Car repair manuals for everyone.

B1235

DTC B1235 or DTC indicator L: A Problem in the Air Mix Control Linkage, Door, or Motor

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

Is DTC B1235 or L Indicated?

YES - Go to step 5.

NO - Intermittent failure.

5. Turn the ignition switch to LOCK (0).
6. Disconnect the air mix control motor 7P connector.
7. Disconnect climate control unit connector A (32P).
8. Check for continuity between the following terminals of the climate control unit connector A (32P) and the air mix 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 air mix control motor.

9. Check for continuity between body ground and climate control unit connector A (32P) No. 9 and No. 11 terminals individually.






Is there continuity?

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

NO - Go to step 10.

10. Test the air mix control motor.

Is the air mix control OK?

YES - Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.

NO - Replace the air mix control motor, or repair the air mix control linkage or door.