Evaporator Temperature Sensor / Switch: Testing and Inspection

On-vehicle inspection

Compressor Controls-Circuit Testing:

1. Remove the glove box.
2. Start the engine and allow it to idle.
3. Turn the A/C switch OFF and set the blower switch to the highest position to operate the blower fan for a few minutes.
4. After a few minutes, turn the blower switch OFF and stop the engine.

Compressor Controls-Circuit Testing:

5. Disconnect the A/C thermostat connector and check for continuity between terminals 1 and 2 of the thermostat.
6. If not as specified, replace the A/C thermostat.

NOTE: The A/C thermostat contacts will be open if the evaporator temperature is below 32.7 ± 1.3° F (0.4 ± 0.7° C).

Inspection

1. Immerse the sensing bulb in a container of ice water.




2. Check continuity between terminals of the thermostat as specified.
3. If not as specified replace the A/C thermostat.