F and Auto

DTC Troubleshooting: B1230 or Indicator F and AUTO

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

1. Clear the DTC with the HDS.

2. Turn the ignition switch to LOCK (0), and then to ON (II).

3. Do the self-diagnostic function with the HDS Initial Inspection and Diagnostic Overview or climate control unit. Initial Inspection and Diagnostic Overview

4. Check for DTCs.

Is DTC B1230 or F and AUTO indicated?
YES - Go to step 5.

NO - Intermittent failure. Check for loose wires or poor connections on the sunlight sensor circuit.


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

6. Disconnect the sunlight sensor 5P connector (with automatic lighting) or 2P connector (without automatic lighting).

7. Disconnect climate control unit connectors A (28P) and B (12P).

8. Check for continuity between climate control unit connector A (28P) terminal No. 25 and body ground.

Is there continuity?
YES - Repair a 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 climate control unit connector A (28P) terminal No. 25 and climate control unit connector B (12P) terminal No. 10.

Is there continuity?
YES - Repair a short in the wires between the climate control unit and the sunlight sensor.

NO - Go to step 10.






10. Reconnect the sunlight sensor 5P connector (with automatic lighting) or 2P connector (without automatic lighting).

11. Reconnect climate control unit connectors A (28P) and B (12P).

12. Test the sunlight sensor. Sunlight Sensor Test

Is the sunlight sensor OK?
YES - Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.

NO - Replace the sunlight sensor. Service and Repair