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, 3 W-18 W 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.