How can I use a multimeter to test a light switch?

To test a light switch using a multimeter, set the multimeter to the resistance or continuity setting. Turn off the power to the switch, remove the switch cover, and disconnect the wires. Touch one multimeter probe to each terminal on the switch. If the multimeter shows continuity or a low resistance reading, the switch is working properly. If there is no continuity or a high resistance reading, the switch may be faulty and needs to be replaced.