Dimmer Switch: Testing and Inspection

INSPECT LIGHT CONTROL RHEOSTAT OPERATION
a. Connect terminals 1 and 3 through a 3.4 W test bulb.
b. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2.
c. Turn the rheostat knob fully counterclockwise, and check that the test bulb goes out.
d. Gradually turn the rheostat knob clockwise, and check that the test bulb brightness changes from dark to bright.
If operation is not as specified, replace the rheostat.