How to Troubleshoot Electrical Problems

All those electrical devices in your house require an unbroken supply of power from your utility company. Here are the basic tests you may need to conduct if you run into an interruption in power or an appliance stops working.

Difficulty:

Moderate

Instructions

Things You'll Need

• Neon Tester
• Tape
• Continuity Tester
• Screwdriver

Reset a circuit breaker

1. When a circuit breaker trips, it moves about midway between the full-on and full-off positions, and it will move back and forth a little when you wiggle it.

2. To reset a tripped breaker, push it to the full-off position (opposite all the other breakers in its column), then to the full-on position, and then let go immediately.

3. If it trips again or does not stay in the On position, push it to the full-off position and tape it over until you've resolved whatever's causing it to trip.

Test a live receptacle

1. Plug the two probes of a continuity tester into the two vertical slots. If there is power, the tester will glow. Test both halves. Some receptacles are powered by two separate circuits.

2. Alternatively, plug a neon tester into the receptacle.

3. It analyzes the wiring, and its lights identify the problem.

Test for power at an open outlet box

1. Shut off power to the circuit at the service panel. Remove the outlet cover and remove the device (a switch or receptacle), or bend out the connected wires and keep the ends apart.

2. Test a device by probing each terminal screw with one lead from a neon tester and probing a metal outlet box or bare grounding wire with the other lead.

3. Test connected wires by removing the wire nut enough to expose bare wire, then probing that wire and either a metal outlet box or the bare grounding wire. Repeat the process for every wire connection.

Test a device for continuity

1. Make sure the wire or device isn't live. Use a neon tester on wiring, or unplug or disconnect a device.

2. Clip one lead onto one terminal of a switch, for example. Probe the other terminal. The tester should light with the switch in the On position and, just as important, should not light in the Off position.

3. Probe the other terminal. The tester should light with the switch in the On position and, just as important, should not light in the Off position.

Tips & Warnings

• Test a continuity tester's battery and bulb by touching the probe and clip together momentarily. The bulb should light.

• A circuit breaker may have a red indicator that signals it has been tripped.

• If a breaker tripped due to a tool or machinery overload, make sure you've switched off or unplugged that tool before restoring power.

• Never use a continuity tester until you have verified that there's no current in the line.

• If you know of or suspect an unresolved problem that has caused the breaker to trip, do not attempt to reset it until you've investigated and corrected the situation.