B and Mode

DTC Troubleshooting: B1240 (B and MODE)

DTC B1240 or DTC indicator B and MODE:

A Problem in the Front Mode Control Linkage, Doors, or Motor Circuit

1. Clear the DTCs 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 B and MODE indicated?

YES -

Go to step 5.

NO -

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

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

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

Is the front mode control motor OK?

YES -

Go to step 7.

NO -

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

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

8. Disconnect climate control unit connector A (40P).

9. Check for continuity between the following terminals of climate control unit connector A (40P) and the front 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 front mode control motor.�

10. Check for continuity between body ground and climate control unit connector A (40P) terminals No. 16 and No. 17 individually.





Is there continuity?

YES -

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