B1230

DTC Troubleshooting: B1230 (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 or the climate control unit.

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.

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.

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 Climate Control Unit Removal/Installation.�

NO -

Replace the sunlight sensor Service and Repair.�