Without Climate Control

DTC Troubleshooting: B1228 (10)

DTC B1228 or DTC indicator 10:

A Short in the Outside Air Temperature Sensor Circuit

1. Clear the DTC with the HDS.

2. Operate the heater-A/C control system in several modes.

3. Check for DTCs using the HDS or the self-diagnostic function.

Is DTC B1228 or 10 indicated?

YES -

Go to step 4.

NO -

Intermittent failure. Check for loose wires or poor connections on the outside air temperature sensor circuit.�

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

5. 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 -

With the outside air temperature sensor disconnected, go to step 6.

NO -

Replace the outside air temperature sensor Service and Repair.�

6. Disconnect the HVAC control unit 30P connector.

7. Check for continuity between body ground and the HVAC control unit 30P connector terminal No. 8.





Is there continuity?

YES -

Repair a short to body ground in the wire between the HVAC control unit and the outside air temperature sensor.�

NO -

Go to step 8.

8. Check for continuity between HVAC control unit 30P connector terminals No. 8 and No. 20.





Is there continuity?

YES -

Repair a short in the wire(s) between the HVAC control unit and the outside air temperature sensor.�

NO -

Substitute a known-good HVAC control unit HVAC Control Unit Removal/Installation (Without Climate Control), and recheck. If the symptom/indication goes away, replace the original HVAC control unit HVAC Control Unit Removal/Installation (Without Climate Control).�