B1227

DTC Troubleshooting: B1227 (TAM sensor open)

DTC B1227 or TAM sensor open is indicated:

An Open in the Outside Air Temperature Sensor Circuit

1. Clear the DTC with the HDS.

2. Turn the ignition switch to LOCK (0), and then back to ON (II).

3. Do the self-diagnostic with the HDS or the climate control unit.

4. Check for DTCs.

Is DTC B1227 or TAM sensor open indicated?

YES -

Go to step 5.

NO -

Intermittent failure. Check for loose wires or poor connections on the outside air temperature sensor circuit.

5. Turn the ignition switch to LOCK (0).

6. Remove the outside air temperature sensor Service and Repair and test it Testing and Inspection.

Is the outside air temperature sensor OK?

YES -

With the outside air temperature sensor disconnected, go to step 7.

NO -

Replace the outside air temperature sensor Service and Repair.

7. Disconnect the climate control unit 40P connector.

8. Check for continuity between climate control unit 40P connector terminal No. 16 and outside air temperature sensor 2P connector terminal No. 2.





Is there continuity?

YES -

Go to step 9.

NO -

Repair an open in the wire between the climate control unit and the outside air temperature sensor.

9. Check for continuity between climate control unit 40P connector terminal No. 33 and outside air temperature sensor 2P connector terminal No. 1.





Is there continuity?

YES -

Check for loose wires or poor connections at the climate control unit 40P connector and at the outside air 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 Climate Control Unit Removal/Installation.

NO -

Repair an open in the wire between the climate control unit and the outside air temperature sensor.