Inspect First

There are two main reasons for replacing a light fixture:

• It isn’t working, and you believe it is somehow broken.
• You want to install an updated style or a fixture that will offer more light.

You should do a number of checks before pronouncing a light fixture broken or beyond repair. You already know about checking the switch and the fixture itself for power. In addition, you should look at the following:

• The lamp (light bulb)
• The socket
• The wire connections inside the box

Checking the light bulb is the obvious first course of action—replacing the bulb with one that’s working. If it got jostled around in a storage drawer or even on the way home from the hardware store, there’s always a chance a new bulb isn’t working, so check it in a fixture or lamp you know is working. The next thing to check is the socket. At the bottom of the socket is a small metal tab that makes contact with the bottom of the lamp. Turn the power off and check with your voltage tester by placing one probe on the metal tab and one on the inside of the metal socket. The bulb should not glow. If it does, the power is still on, and you need to shut off the correct circuit. With the correct circuit shut off, test the fixture again with your voltage tester. With the power off, pull the end of the tab up a little bit using the end of a screwdriver. Screw in the lamp, turn on the power, and try the fixture again. These tabs sometimes become depressed or flattened out and don’t form a tight contact with the lamp. Why would the contact suddenly be broken? All it takes is a slight vibration in the fixture from, say, a large truck passing by. If a light bulb that you know is good doesn’t work, you have a problem with the socket. Remove the fixture to test the socket by following these steps:

1. With all glass globes, lampshades, and light bulbs removed, unscrew the fixture from the box by turning the mounting screws counterclockwise.
2. Carefully pull down the fixture and let it rest on top of the ladder. This is critical if it’s a heavy fixture.
3. Disconnect the wires from the terminal screws and take down the fixture.
4. Attach the continuity tester’s clip to the hot wire terminal screw, and place the probe against the metal tab in the socket. If the tester does not glow, the socket needs to be replaced.
5. Attach the continuity tester’s clip to the neutral terminal and the probe to the threaded portion of the socket. Again, if the tester’s bulb does not glow, the socket needs replacement.

Some sockets are permanently attached to the fixture, in which case the entire fixture must be replaced. Others are attached to the fixture with screws and can be removed and replaced. Take your old socket to the hardware, lighting, or electrical-supply store and purchase an identical replacement.
The same vibrations also can cause the wire connections to come loose just enough to lose contact with the fixture.