Operation CHARM: Car repair manuals for everyone.

B1226

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. Operate the climate control system in several modes.
3. Check for DTCs using the HDS or self-diagnostic.

Is DTC B1226 or TR sensor short indicated?

YES - Go to step 4.

NO - Intermittent failure.

4. Turn the ignition switch OFF.
5. Remove the in-car temperature sensor and test it.

Is the in-car temperature sensor OK?

YES - Go to step 6.

NO - Replace the in-car temperature sensor.

6. Disconnect the climate control unit 40P connector.




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

Is there continuity?

YES - Repair short to body ground in the wire between the climate control unit and the in-car temperature sensor.

NO- Go to step 8.




8. Check for continuity between the No. 15 terminal and the No. 33 terminal of the climate control unit 40P connector.

Is there continuity?

YES - Repair 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.