DTC L

DTC indicator L: An Open in the Heater Core Temperature Sensor Circuit.

1. Disconnect the heater core temperature sensor 2P connector.




2. Measure the resistance between the No. 1 and No. 2 terminals of the heater core temperature sensor.

Is the resistance within the specifications shown on the graph?

YES - Go to step 3.

NO - Replace the heater core temperature sensor.

3. Disconnect climate control unit connector B (22P).




4. Check for continuity between the No. 4 terminal of climate control unit connector B (22P) and the No. 2 terminal of the heater core temperature sensor 2P connector.

Is there continuity?

YES - Go to step B.

NO - Repair open in the wire between the climate control unit and the heater core temperature sensor.




5. Check for continuity between the No. 5 terminal of climate control unit connector B (22P) and the No. 1 terminal of the heater core temperature sensor 2P connector.

Is there continuity?

YES - Check for loose wires or poor connections at climate control unit connector B (22P) and at the heater core 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.

NO - Repair open in the wire between the climate control unit and the heater core temperature sensor.