To test a circuit breaker using a multimeter, remove the circuit breaker box cover and turn the switch on. Using the multimeter's red prong, touch the screw that connects to the breaker. Touch the grounded box using the black prong. If there's no voltage reading, then the breaker is faulty.
- Take safety precautions
Switch off or unplug all electrical appliances in the area fed by the suspect circuit breaker. Manually test the breaker by flipping it back and forth. If it doesn't stay on the "on" position, the breaker is faulty and needs replacing.
- Remove the breaker box cover, and turn on the switch
Using a screwdriver, remove all the screws that hold the cover in place. Remove the cover to reveil the wires that supply power to the breaker. Turn the circuit breaker's switch to the "on" position.
- Test the breaker
Turn on your multimeter and set it to read voltage. Use the multimeter's red prong to touch the screw that connects the breaker to a black wire. Touch the multimeter black prong to the grounded box. Check the multimeter for a reading or a light indicator. If there is a voltage reading of either 120 or 220 volts, then the circuit breaker is okay. If there is no reading, then no power is reaching the breaker and it needs to be replaced.