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Evaporator Temperature Sensor / Switch: Testing and Inspection

A/C Thermostat Test





Connect battery power to terminal C and ground terminal B, and connect a test light between terminals A and C.

NOTE: Use a 12 V, 3W - 18W test light.

Dip the A/C thermostat into a cup filled with ice water, and check the test light.

The light should go OFF at 37°F (3°C) or less, and should come ON at 39°F (4°C) or more.

If the light doesn't come on and go off as specified, replace the A/C thermostat.