B1225
DTC B1225 or DTC indicator A: An Open in the In-car Temperature Sensor Circuit1. Clear the DTC by turning the ignition switch OFF, and then ON (II).
2. Operate the climate control system in several modes.
3. Check for DTCs using the self-diagnostic or HDS.
Is DTC B1225 or A indicated?
YES - Go to step 4.
NO - Intermittent failure, check for loose wires or poor connections on the in-car temperature sensor circuit.
4. Turn the ignition switch OFF.
5. Remove the in-car temperature sensor and test it.
Is the in-car temperature sensor OK?
YES - Go to step 6.
NO - Replace the in-car temperature sensor.
6. Disconnect climate control unit connector A (20P).
7. Check for continuity between the No. 15 terminal of climate control unit connector A (20P) and the No. 2 terminal of the in-car temperature sensor 2P connector.
Is there continuity?
YES - Go to step 8.
NO - Repair open in the wire between the climate control unit and the in-car temperature sensor.
8. Check for continuity between the No. 5 terminal of climate control unit connector A (20P) and the No. 1 terminal of the in-car temperature sensor 2P connector.
Is there continuity?
YES - Check for loose wires or poor connections at climate control unit connector A (20P) 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.