Operation CHARM: Car repair manuals for everyone.

DTC I

DTC B1233 or DTC indicator I: An Open in the Driver's Air Mix Control Motor Circuit

1. 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 B1233 or I indicated?

YES - Go to step 4.

NO - Intermittent failure, check for loose wires or poor connections on the driver's air mix control motor circuits

4. Turn the ignition switch OFF.
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.

6. Disconnect the driver's air mix control motor 7P connector.
7. Disconnect the climate control unit 30P connector.
8. Check for continuity between the following terminals of the climate control unit 30P connector and the driver's air mix control motor 7P connector.






Is there continuity?

YES - Check for loose wires or poor connections at the climate control unit 30P connector and at the driver's air mix control motor 7P connector. If the connections are good, substitute a known-good climate control unit and recheck. If the symptom/indication goes away, replace the original climate control unit.

NO - Repair open in the wires between the climate control unit and the driver's air mix control motor.