Testing a light switch this is a question that comes up often and here is the answer.
Voltage meter light switch.
Why a tester may read voltage while the light switch is off.
After doing this turn on and off the light switch and when it is on the reading should be near to zero.
You ll need screwdrivers usually one flat head and one phillips for removing the switch and disconnecting the switch wires.
You also need a non contact voltage tester to check the switch and wires for power before touching them.
Disconnect the two switch wires and spread the bare ends so they don t touch one another photo 1.
If not you could have a bad breaker bad wiring or a bad switch.
This video will show you how to check your light switch and how to replace a.
And for making the test you ll need either a continuity tester or a.
If you read 120 volts the light fixture is good.
Turn the power back on and identify the hot wire with the non contact tester.
You must fix the problem to a point where you have 120 volts at the input to the fixture.
With your multimeter touch all the tester probe to any other screw terminal.
The tester will produce a voltage reading if the switch is good however sometimes you can get false voltage reading which i will explain below.
Touch the voltmeter to the input wires or connections.
Tools for testing light switches.
Nevertheless when the light switch is off the reading shown should be 1 which means no continuity.