Test Wall Light Switch

This type of tester has two lead wires that uses the battery voltage of the tester to test a circuit which in this example is the circuit components of a switch.
Test wall light switch. Wave the voltage tester all around the front and sides of the switch without making direct contact. Testing a switch with a continuity tester. Clip the wire of a continuity tester to one of the screw terminals and touch the other terminal with the tester probe. Turn the switch lever on and off.
After that loosen the screws that hold the switch into the electrical box. Test the ground wires in the wall switch with a two lead circuit tester which has a red and a black lead running into black body with a small light. The tester should light up when the switch lever is in the on position but should not light up when the switch lever is off. You will need to take them completely out of the box to free up the switch.
The most common methods for testing a light switch. Test the switch for continuity. Keep the circuit breaker flipped off for this. A continuity tester can be used to test the light switch while the circuit is off or the switch has been removed.