Dimmer Switch: Testing and Inspection

INSPECT LIGHT CONTROL RHEOSTAT
a. Turn the rheostat knob OFF, and check that there is no continuity between terminals. (Rheostat knob turned to fully counterclockwise.)
b. Gradually, turn the rheostat knob from the dark side to bright side, and check that the resistance decreases from 10 to 0 ohm (Rheostat knob turned to clockwise.)
If operation is not as specified, replace the rheostat.