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Before you begin

Remember the cardinal rule of electrical work: make sure the power is off before you start! Turn off the circuit breaker or remove the fuse before starting. To double check, turn a switch or an appliance on and off. A more reliable way to check the power on an outlet is to buy a test lamp from your local hardware store. The wires of the lamp go into the outlet, and if the lamp lights, the circuit is still powered up. If it doesn’t light, you should be safe.

Organization

It’s probably a good idea to write down each step of the process you go through in checking and fixing the outlets or switches. Include the parts added and removed, the tools used, and the tests performed. It may seem tedious, but it could save you from a major headache later on.

Troubleshooting

If a particular breaker or fuse trips or blows all the time, shutting down power, the problem is probably an overload on that particular circuit. This isn’t much of a problem in newer homes, which are designed to provide consistent current to high-tech appliances like computers and stereo systems. In older homes, however, a circuit with too many appliances or lights on it might be the cause of the problem. Frequently, one heavy-duty appliance will consistently trip the breaker; if you suspect this is the case, try turning on appliances one by one until you find the culprit.

If that doesn’t solve the problem, unplug all the appliances and turn off all the switches on the blown circuit. Then turn the power back on. If the circuit breaks, you know the problem is in the wiring and components.

Turn the power off again, and check each switch and outlet, looking for broken or loose wires and screws. After each replacement, test the circuit again, but don’t forget to turn the power off if you need to perform additional repairs.

After you’ve fixed the wires and screws, try the switches and appliances again. If the circuit breaks when turning one of them on, you have yet another problem.

Test the switch with a continuity tester, a device with a bulb and a probe at one end and an alligator clip on the other. Using a continuity tester is easy: just put the probe on one terminal and attach the clip to the other. If the bulb lights up, the switch is OK and the problem is probably in the appliance. If it doesn’t light up, the reverse is true.

If you’ve gone through all the steps and the problem persists, call an electrician. There’s no reason why you can’t do simple repairs yourself, but more complicated problems call for a higher level of expertise.