Open or Short In the Mode Control Motor Circuit

DTC Troubleshooting: B1239 (A)

DTC B1239 or DTC indicator A:

An Open or Short in the Mode Control Motor Circuit

NOTE: If DTC B1239 is detected with HDS, it is not necessary to do step 1.

1. Check the sensor input display mode, and select "mode control motor" according to the table.

NOTE: This indication by segment lit on digital segments is assigned for 2 failure causes that it is necessary to decide which one is a true cause. If there is a failure in the sensor or motor, a value correspondent to the sensor or motor in the Sensor Input Display Mode is displayed as "Er", which serves to specify which is a true cause.

Is sensor value indicated "Er"?

YES -

Go to step 2

NO -

Go to troubleshooting DTC B1225 or DTC indicator A B1225

2. Clear the DTC with the HDS.

3. Turn the ignition switch to LOCK (0), and then back to ON (II).

4. Do the self-diagnostic with the HDS or the climate control unit.

5. Check for DTCs.

Is DTC B1239 or A indicated?

YES -

Go to step 6.

NO -

Intermittent failure. Check for loose wires or poor connections on the mode control motor circuit.

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

7. Test the mode control motor Mode Control Motor Test.

Is the mode control motor OK?

YES -

Go to step 8.

NO -

Replace the mode control motor Mode Control Motor Replacement.

8. Disconnect the mode control motor 7P connector.

9. Disconnect climate control unit connector A (24P).

10. Check for continuity between the following terminals of climate control unit connector A (24P) and the mode control motor 7P connector.









Is there continuity?

YES -

Go to step 11.

NO -

Repair an open in the wire(s) between the climate control unit and the mode control motor.

11. Check for continuity between body ground and climate control unit connector A (24P) terminals No. 1, 2, 3, and 4 individually.





Is there continuity?

YES -

Repair a short to body ground in the wire(s) between the climate control unit and the mode control motor.

NO -

Go to step 12.

12. Check for continuity between the terminals of climate control unit connector A (24P) as follows.





Is there continuity between any of the terminals?

YES -

Repair a short in the wire(s) between climate control unit and mode control motor.

NO -

Go to step 13.

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





Is there any voltage?

YES -

Repair a short to power in the wire(s) between the climate control unit and the mode control motor.

NO -

Check for loose wire or poor connections at climate control unit connector A (24P) and at the mode 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 Climate Control Unit Removal/Installation.