Intermittent failure, check for loose wires or poor connections in the in-car temperature sensor circuit.?
5. Turn the ignition switch to LOCK (0).
6. Remove the humidity/in-car temperature sensor See: Heating and Air Conditioning/Cabin Temperature Sensor / Switch/Service and Repair,
and test it.
Is the in-car temperature sensor OK?
YES -
With the humidity/in-car temperature sensor disconnected, go to step 7.
NO -
Replace the humidity/in-car temperature sensor See: Heating and Air Conditioning/Cabin Temperature Sensor / Switch/Service and Repair.?
7. Disconnect climate control unit connector A (40P).
8. Check for continuity between climate control unit connector A (40P) terminal No. 5 and body ground.
Is there continuity?
YES -
Repair a short to body ground in the wire between the climate control unit and the in-car temperature sensor.?
NO -
Go to step 9.
9. Check for continuity between climate control unit connector A (40P) terminals No. 5 and No. 8.
Is there continuity?
YES -
Repair a short in the wires between the climate control unit and the in-car temperature sensor.?
NO -
Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit See:
Heating and Air Conditioning/Control Assembly/Service and Repair/Climate Control Unit Removal/Installation.?
B and Mode
DTC Troubleshooting: B1240 (B and MODE)
DTC B1240 or DTC indicator B and MODE:
