E and AUTO

DTC Troubleshooting: B1229 (E and AUTO)

DTC B1229 or DTC indicator E and AUTO:

An Open in the Sunlight Sensor Circuit

1. Clear the DTC with the HDS.

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

3. Do the Self-Diagnostic Function with the HDS or the climate control unit.

4. Check for DTCs.

Is DTC B1229 or E 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 sunlight sensor 5P connector terminal No. 4.





Is there continuity?

YES -

Go to step 9.

NO -

Repair an open in the wire between the climate control unit and the sunlight sensor.

9. Check for continuity between climate control unit connector B (12P) terminal No. 10 and sunlight sensor 5P connector terminal No. 2.





Is there continuity?

YES -

Go to step 10.

NO -

Repair an open in the wire between the climate control unit and the sunlight sensor.

10. Reconnect the sunlight sensor 5P connector.

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

12. Test the sunlight sensor Testing and Inspection.

Is the sunlight sensor OK?

YES -

Check for loose wires or poor connections at climate control unit connector and at the sunlight sensor 5P connector. If the connections are good, 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.