A

DTC Troubleshooting: B1225 or Indicator A

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

1. Clear the DTC with the HDS.

2. Operate the climate control system in several modes.

3. Check for DTCs using the HDS or the self-diagnostic function.

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 to LOCK (0).

5. Remove the in-car temperature sensor, Service and Repair and test it. In-Car Temperature Sensor Test (With Climate Control)

Is the in-car temperature sensor OK?
YES - Go to step 6.

NO - Replace the in-car temperature sensor. Service and Repair


6. Disconnect the climate control unit 30P connector.

7. Check for continuity between climate control unit 30P connector terminal No. 8 and the in-car temperature sensor 2P connector terminal No. 1.

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 climate control unit 30P connector terminal No. 22 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 30P connector and the in-car temperature sensor 2P connector. If the connections are good, substitute a known-good climate control unit, Climate Control Unit Removal/Installation (With Climate Control) 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.