DTC Troubleshooting: B1225 or Indicator A and AUTODTC 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 to LOCK (0), and then to ON (II).
3.
Do the self-diagnostic with the HDS
Initial Inspection and Diagnostic Overview or climate control unit.
Initial Inspection and Diagnostic Overview 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 to LOCK (0).
6.
Remove the in-car temperature sensor
Service and Repair and test it.
In-Car Temperature Sensor Test Is the in-car temperature sensor OK?
YES - Go to step 7.
NO - Replace the in-car temperature sensor.
7.
Disconnect climate control unit connector B (16P).
8.
Check for continuity between the climate control unit connector B (16P) No. 14 terminal and the in-car temperature sensor 2P connector No. 1 terminal.
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) No. 4 terminal and the in-car temperature sensor 2P connector No. 2 terminal.
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.
