B1230

DTC indicator F or DTC B1230: A Short in the Sunlight Sensor Circuit

1. 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 F or B1230 indicated?

YES - Go to step 4.

NO - intermittent failure.

4. Turn the ignition switch OFF.
5. Test the sunlight sensor.

Is the sunlight sensor OK?

YES - Go to step 6.

NO - Replace the sunlight sensor.

6. Disconnect the sunlight sensor 2P connector.
7. Disconnect climate control unit connector A (20P).




8. Check for continuity between the No.17 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 sunlight sensor.

NO - Go to step 9.




9. Check for continuity between the No.17 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 sunlight sensor.

NO - Substitute a known good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.