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 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 Sunlight Sensor Test.

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.�