B1228
DTC B1228 or DTC indicator D: A Short in the Outside Air Temperature Sensor Circuit1. Clear the DTC by turning the ignition switch OFF, and then ON (II).
2. Operate the climate control system in several modes.
3. Check for DTCs using the self-diagnostic or HDS.
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.
Does the outside air temperature sensor test OK?
YES - Go to step 6.
NO - Replace the outside air temperature sensor.
6. Disconnect climate control unit connector A (20P).
7. Check for continuity between the No. 16 terminal of climate control unit connector A (20P) 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 No. 16 terminal and the No. 5 terminal of climate control unit connector A (20P).
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.