B and AUTO

DTC Troubleshooting: B1226 (B and AUTO)

DTC B1226 or DTC indicator B and AUTO:

A Short in the In-car Temperature Sensor Circuit

1. Clear the DTC by turning the ignition switch to LOCK (0), and then turn to ON (II).

2. Operate the climate control system in several modes.

3. Check for DTCs using the HDS How to Troubleshoot the Climate Control System or self-diagnostic function How to Troubleshoot the Climate Control System.

Is DTC B1226 or B and AUTO indicated?

YES -

Go to step 4.

NO -

Intermittent failure.�

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

5. Remove the in-car temperature sensor In-car Temperature Sensor Replacement and test it In-car Temperature Sensor Test.

Does the in-car temperature sensor test OK?

YES -

Go to step 6.

NO -

Replace the in-car temperature sensor.�

6. Disconnect the front climate control unit 30P connector.

7. Check for continuity between front climate control unit 30P connector terminal No. 18 and body ground.





Is there continuity?

YES -

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

NO -

Go to step 8.

8. Check for continuity between front climate control unit 30P connector terminals No. 18 and No. 29.





Is there continuity?

YES -

Repair a short in the wires between the front climate control unit and the in-car temperature sensor.�

NO -

Substitute a known-good front climate control unit, and recheck. If the symptom/indication goes away, replace the original front climate control unit Front Climate Control Unit Removal/Installation.�