Manufacturer Code Charts: 4

DTC Troubleshooting: B1239 (4)

DTC B1239 or DTC indicator 4:

An Open or Short in the Front Mode Control Motor Circuit

1. Clear the DTC by turning the ignition switch to LOCK (0), and then turn to ON (II).

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

3. Check for DTCs using the HDS How to Troubleshoot the Heating and A/C Systems or self-diagnostic function How to Troubleshoot the Heating and A/C Systems.

Is DTC B1239 or 4 indicated?

YES -

Go to step 4.

NO -

Intermittent failure, check for loose wires or poor connections on the front mode control motor circuit.�

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

5. Test the front mode control motor Front Mode Control Motor Test.

Is the front mode control motor OK?

YES -

Go to step 6.

NO -

Replace the front mode control motor Front Mode Control Motor Replacement.�

6. Disconnect the front mode control motor 7P connector.

7. Disconnect A/C control panel connector A (22P).

8. Check for continuity between the following terminals of A/C control panel connector A (22P) and the front mode control motor 7P connector.









Is there continuity?

YES -

Go to step 9.

NO -

Repair an open in the wire(s) between the A/C control panel and the front mode control motor.�

9. Check for continuity between body ground and A/C control panel connector A (22P) terminals No. 3, 15, 16, 17, and 18 individually.





Is there continuity?

YES -

Repair a short to body ground in the wire(s) between the A/C control panel and the front mode control motor.�

NO -

Go to step 10.

10. Check for continuity between terminals of A/C control panel connector A (22P) as follows.





Is there continuity between any of the terminals?

YES -

Repair a short in the wires.�

NO -

Go to step 11.

11. Turn the ignition switch to ON (II), and measure the same terminals for voltage to body ground.





Is there any voltage?

YES -

Repair a short to power in the wire(s) between the A/C control panel and the front mode control motor. This short may also damage the A/C control panel. Repair the short to power before replacing the A/C control panel.�

NO -

Check for loose wire or poor connections at A/C control panel connector A (22P) and at the front mode control motor 7P connector. If the connections are good, substitute a known-good A/C control panel, and recheck. If the symptom/indication goes away, replace the original A/C control panel A/C Control Panel Removal/Installation.�