B1225

DTC B1225 or DTC indicator A and AUTO: An Open in the In-car Temperature Sensor Circuit

1. Clear the DTC with the HDS.
2. Turn the ignition switch OFF, and then ON (II).
3. Do the self-diagnostic with the HDS or climate control unit.
4. Check for DTCs.

Is DTC B1225 or A and AUTO indicated?

YES - Go to step 5.

NO - Intermittent failure, check for loose wires or poor connections on the in-car temperature sensor circuit.

5. Turn the ignition switch OFF.
6. Remove the in-car temperature sensor and test it.

Is the in-car temperature sensor OK?

YES - Go to step 7.

NO - Replace the in-car temperature sensor.

7. Disconnect the climate control unit connector B (16P).




8. Check for continuity between the climate control unit connector B (16P) terminal No. 14 and the in-car temperature sensor 2P connector terminal No. 1.

Is there continuity?

YES - Go to step 9.

NO - Repair open in the wire between the climate control unit and the in-car temperature sensor.




9. Check for continuity between climate control unit connector B (16P) terminal No. 4 and the in-car temperature sensor 2P connector terminal No. 2.

Is there continuity?

YES - Check for loose wires or poor connections at the climate control unit connector B (16P) and at the in-car temperature sensor 2P 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.

NO - Repair open in the wire between the climate control unit and the in-car temperature sensor.