B2997

DTC B2997 or DTC indicator H and AUTO: A Short in the Heater Core Temperature Sensor Circuit

1. Clear the DTC with the HDS.
2. Turn the ignition switch OFF, and then ON (II).
3. Do the self-diagnostic with the HDS or climate control unit.
4. Check for DTCs.

Is DTC B2997 or H and AUTO indicated?

YES - Go to step 5.

NO - Intermittent failure.

5. Turn the ignition switch OFF.
6. Remove the heater core temperature sensor, and test it.

Is the heater core temperature sensor OK?

YES - Go to step 7.

NO - Replace the heater core temperature sensor.

7. Disconnect climate control unit connector A (32P) and B(16P).




8. Check for continuity between body ground and the heater core temperature sensor 2P connector terminals No. 1 and No. 2 individually.

Is there continuity?

YES - Repair short to body ground in the wire(s) between the climate control unit and the heater core temperature sensor.

NO - Go to step 9.




9. Check for continuity between the heater core temperature sensor 2P connector terminals No. 1 and No. 2.

Is there continuity?

YES - Repair short in the wires between the climate control unit and the heater core temperature sensor.

NO - Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.