Without Climate Control

DTC Troubleshooting: B1233 (1)

DTC B1233 or DTC indicator 1:

An Open in the Air Mix Control Motor Circuit

1. Clear the DTC with the HDS.

2. Operate the heater-A/C control system in several modes.

3. Check for DTCs using the HDS or the self-diagnostic function.

Is DTC B1233 or 1 indicated?

YES -

Go to step 4.

NO -

Intermittent failure. Check for loose wires or poor connections on the air mix control motor circuit.�

4. Turn the ignition switch to LOCK (0).

5. Disconnect the air mix control motor 7P connector.

6. Disconnect the HVAC control unit 30P connector.

7. Check for continuity between the following terminals of the HVAC control unit 30P connector and the air mix control motor 7P connector.









Is there continuity?

YES -

Go to step 8.

NO -

Repair an open in the wire(s) between the HVAC control unit and the air mix control motor.�

8. Test the air mix control motor Air Mix Control Motor Test (Without Climate Control).

Is the air mix control motor OK?

YES -

Check for loose wires or poor connections at the HVAC control unit 30P connector and the air mix control motor 7P connector. If the connections are good, substitute a known-good HVAC control unit HVAC Control Unit Removal/Installation (Without Climate Control). and recheck. If the symptom/indication goes away, replace the original HVAC control unit HVAC Control Unit Removal/Installation (Without Climate Control).�

NO -

Replace the air mix control motor Air Mix Control Motor Replacement (Without Climate Control).�