B1226

DTC Troubleshooting: B1226 (TR sensor short)

DTC B1226 or TR sensor short is indicated:

A Short in the In-Car 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 B1226 or TR sensor short 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 Testing and Inspection.

Is the in-car temperature sensor OK?

YES -

With the in-car temperature sensor disconnected, go to step 7.

NO -

Replace the in-car temperature sensor Service and Repair.

7. Disconnect the climate control unit 40P connector.

8. Check for continuity between body ground and climate control unit 40P connector terminal No. 15.





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 40P connector terminals No. 15 and No. 33.





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 Climate Control Unit Removal/Installation.