No Power

The whole house

Power company
Main circuit breaker in or near main electrical panel

A few lights and/or outlets

Tripped circuit breaker
Tripped GFCI or AFCI outlet
Loose wire makeup, loose connection to switch, light fixture, or outlet inside of electrical box

One light

Bad bulb
Bad light switch Troubleshooting Single Pole Light Switch
Bad light fixture Troubleshooting Light Fixtures
Loose wire makeup, loose connection to switch, light fixture, or outlet inside of electrical box

One outlet

GFCI or AFCI outlet
Tripped circuit breaker
Loose wire makeup, loose connection to switch, light fixture, or outlet inside of electrical box
Bad outlet

Sometimes power may be lost to a light fixture, outlet, appliance, or electronics. Other times a circuit breaker, GFCI or AFCI will trip for some unknown reason. In this section we will try to help you understand and fix the problem before calling an electrician.

Flickering Lights and Intermittent Loss of Power

Flickering lights and an intermittent loss of power are usually attributed to a loose wire connection. A loose wire connection can cause the wire to overheat, eventually causing the connection to fail. Sometimes a loose connection will make a crackling noise. A loose wire connection could happen in any of these places:

Wire connection to circuit breaker or neutral bar inside electrical panel.
Loose wire makeup, loose connection to switch, light fixture, or outlet inside of electrical box.
Listening for a crackling noise may help in locating the loose connection.
Loose wire connection on power company transformer or equipment.

Tripped Circuit Breaker

Trips right away (within a few seconds)

A malfunctioning electrical load that draws more current than the rating of the circuit breaker
Too many high wattage appliances on a circuit
Short circuit
Damaged electrical cord

Trips occasionally

A malfunctioning electrical load that draws more current than the rating of the circuit breaker
Too many high wattage appliances on a circuit

Electrical Troubleshooting

Circuit Breaker Trips Frequently

When a properly working circuit breaker trips frequently and there are no malfunctioning loads on the circuit, it means the circuit is overloaded. Using more than one space heater or hair dryer at the same time is a common cause of this problem.

After the circuit breaker trips, test for power at nearby outlets. Any outlet that still has power when a breaker trips is located on a different circuit.
Try moving one of the loads to one of the other outlets that still have power.