B1228

DTC Troubleshooting: B1228 (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 back to ON (II).

3. Do the self-diagnostic function with the HDS or the 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 Outside Air Temperature Sensor Replacement (With Climate Control) and test it Outside Air Temperature Sensor Test (With Climate Control).

Is the outside air temperature sensor OK?

YES -

With the outside air temperature sensor disconnected, go to step 7.

NO -

Replace the outside air temperature sensor Outside Air Temperature Sensor Replacement (With Climate Control).�

7. Disconnect the climate control unit 36P connector.

8. Check for continuity between body ground and climate control unit 36P connector terminal No. 10.





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 36P connector terminals No. 10 and No. 22.





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 Climate Control Unit Removal/Installation.�