Heater Core Case: Testing and Inspection

INSPECTION

1. CHECK EVAPORATOR FINS FOR BLOCKAGE
If the fins are clogged, clean them with compressed air.

NOTE: Never use water to clean the evaporator.

2. CHECK FITTINGS FOR CRACKS OR SCRATCHES
Repair as necessary.

3. INSPECT EVAPORATOR TEMPERATURE SENSOR




a. Place the sensor in cold water, and while changing the temperature of water, measure resistance at the connector and at the same time, measure temperature of water with a thermometer.




b. Compare the 2 readings on the chart.
If resistance is not as specified, replace the thermistor.