B1220
DTC B1220 or DTC indicator D: A Short in the Recirculation Control Motor Circuit1. Clear the DTC with the HDS.
2. Turn the ignition switch to LOCK (0), and then ON (II).
3. Do the self-diagnostic with the HDS or climate control unit.
4. Check for DTCs.
Is DTC B1220 or D indicated?
YES - Go to step 5.
NO - Intermittent failure.
5. Turn the ignition switch to LOCK (0).
6. Test the recirculation control motor.
Is the recirculation control motor OK?
YES - Go to step 7.
NO - Replace the recirculation control motor.
7. Disconnect the recirculation control motor 7P connector.
8. Disconnect the climate control unit 36P connector.
9. Check for continuity between body ground and the climate control unit 36P connector No. 13 and No. 19 terminals individually.
Is there continuity?
YES - Repair short to body ground in the wire(s) between the climate control unit and the recirculation control motor.
NO - Go to step 10.
10. Check for continuity between the climate control unit 36P connector No. 13 and No. 19 terminals.
Is there continuity?
YES - Repair short in the wires.
NO - Go to step 11.
11. Turn the ignition switch to ON (II), and check the same terminals for voltage to body ground.
Is there any voltage?
YES - Repair short to power in the wire(s) between the climate control unit and the recirculation control motor. This short may also damage the climate control unit. Repair the short to power before replacing the climate control unit.
NO - Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.