B1228

DTC B1228 or DTC indicator D and AUTO: A Short in the Outside Air Temperature Sensor Circuit

1. Clear the DTC with the HDS.
2. Turn the ignition switch OFF and then ON (II).
3. Do the self-diagnostic with the HDS or climate control unit.
4. Check for DTCs.

Is DTC B1228 or D and AUTO indicated?

YES - Go to step 5.

NO - Intermittent failure.

5. Turn the ignition switch OFF.
6. Remove the outside air temperature sensor, and test it.

Is the outside air temperature sensor OK?

YES - Go to step 7.

NO - Replace the outside air temperature sensor.

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




8. Check for continuity between climate control unit connector A (40P) terminal No. 28 and body ground.

Is there continuity?

YES - Repair short to body ground in the wire between the climate control unit and the outside air temperature sensor.

NO - Go to step 9.




9. Check for continuity between climate control unit connector A (40P) terminals No. 8 and No. 28.

Is there continuity?

YES - Repair short in the wires between the climate control unit and the outside air temperature sensor.

NO - Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.