D and Auto

DTC Troubleshooting: B1228 or Indicator D and AUTO

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 to LOCK (0), and then to ON (II).

3. Do the self-diagnostic function with the HDS Initial Inspection and Diagnostic Overview or climate control unit. Initial Inspection and Diagnostic Overview

4. Check for DTCs.

Is DTC B1228 or D and AUTO indicated?
YES - Go to step 5.

NO - Intermittent failure. Check for loose wires or poor connections on the outside air temperature sensor circuit.


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

6. Remove the outside air temperature sensor, Service and Repair and test it. Outside Air Temperature Sensor Test

Is the outside air temperature sensor OK?
YES - Go to step 7.

NO - Replace the outside air temperature sensor.


7. Disconnect climate control unit connectors A (28P) and B (12P).

8. Check for continuity between climate control unit connector A (28P) terminal No. 24 and body ground.

Is there continuity?
YES - Repair a 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 (28P) terminal No. 24 and climate control unit connector B (12P) terminal No. 10.

Is there continuity?
YES - Repair a 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.