J and A/C

DTC Troubleshooting: B1240 (J and A/C)

DTC B1240 or DTC indicator J and A/C ON:

A Problem in the Mode Control Motor Circuit, Linkage, Door, or Motor

1. Clear the DTC with the HDS.

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

3. Do the Self-Diagnostic Function with the HDS or the climate control unit.

4. Check for DTCs.

Is DTC B1240 or J and A/C ON indicated?

YES -

Go to step 5.

NO -

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

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

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

Is the mode control motor OK?

YES -

Go to step 7.

NO -

Replace the mode control motor Mode Control Motor Replacement, or repair the mode control linkage or doors.

7. Disconnect the mode control motor 7P connector.

8. Disconnect climate control unit connector A (28P).

9. Check for continuity between the following terminals of climate control unit connector A (28P) and the mode control motor 7P connector.









Is there continuity?

YES -

Go to step 10.

NO -

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

10. Check for continuity between body ground and climate control unit connector A (28P) terminals No. 7 and No. 8 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 -

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.