Electronic Climate Control
DTC B1228 or DTC indicator D: A Short in the Outside Air Temperature Sensor Circuit1. Clear the DTC with the HDS.
2. Operate the climate control system in several modes.
3. Check for DTCs using the HDS or self-diagnostic.
Is DTC B1228 or D indicated?
YES - Go to step 4.
NO - Intermittent failure.
4. Turn the ignition switch OFF.
5. Remove the outside air temperature sensor and test it.
Is the outside air temperature sensor OK?
YES - Go to step 6.
NO - Replace the outside air temperature sensor.
6. Disconnect the climate control unit 30P connector.
7. Check for continuity between the climate control unit 30P connector terminal No. 9 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 8.
8. Check for continuity between the climate control unit 30P connector terminals No. 9 and No. 22.
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.