Repair Topics

Knowing how to install a light fixture can be useful and save money. Many light fixtures are relatively easy to install, there are just few steps and some precautions to take.

For related information see the articles, 'Troubleshooting Residential Wiring' and 'Basic House Wiring'. These articles have other resources related to electrical light wiring.

Removing the Old Light Fixture

wiring-lights-pic4Before removing a light fixture you want to turn off the power to the light. Don't just turn off the switch. With the switch off you will still have hot wires in the boxes. Tag the breaker so that no on turns it on.

It is possible to have wires from more than one circuit running through a box. Use a not contact voltage tester to make sure everything is off before you touch any of the wires.

On some fixtures you will have to remove the globe and the light bulbs to get at the base plate. Most lights are held in place by a couple of screws. For fixtures with a globe and base plate, they will likely be phillips head screws. Fixtures with and open frame work and exposed fasteners will have a matching cap screw.

Loosen the screws and allow the light to hang by the wires. This is where you might consider taking a picture. Got a photographic memory? Great, don't bother with the picture. For the rest of us mortals a picture could be a life saver later.

Check one more time to make sure the power is off before you unhook the wires. Use a tester to do this. A non contact tester is the best. Satisfied that the power is off? Now you can unhook the wires, save the wire nuts, just in case.

Installing the New Light

Installing a light fixture is not a difficult task. Be honest, how much time did you spend deciding on the which fixture to buy? It is quite possible that you will have far less time invested in the actual installation of the light fixture.

wiring-lights-pic5At this point, you should have already removed the old fixture. Now comes the hard part. you will need to look at the instruction for assembling your new fixture. Your new fixture will likely come with a new mounting bracket and a screw kit. Locate all of the parts and you are ready to begin.

Subject to what you read in the instruction, installing a light fixture will likely proceed in the following order: (1) Install the mounting bracket to the box. (2) Hook up the wires for the base plate. (3) Install the base plate. (4) Install the trim and/or globes. (5) Install the bulbs. Assemble the fixture per the instructions. Be careful, the parts are usually fairly delicate. If you have to force something, you are probably doing it wrong.

For the wiring, hook the black up to the hot leg from the switch. The white wire from the light will hook up to the neutral, usually the white wire. Most new lights also come with a ground wire. This hooks up to the bare ground wire.

There are lots of different sizes and styles of lights. You will need to take a look at the directions when you assemble the fixture. You may need some help with medium to large fixtures. Especially when you are trying to hold it up and connect the wires.

wiring-lights-pic3Wiring layouts for lights can vary from house to house. Wiring lights for residential homes is fairly straightforward. Lights use a standard 15 or 20 amp 120 volt circuit. Lights can also be fed by circuits that have other things on them such as outlets.

The power for the light can be in the box for the switch or at the light. When the power is at the switch you will generally hook the hot wire to one side of the switch and the hot wire for the switch leg to the other side. You can use a tester to see which one hot.

The white wire coming back from the light will get hooked to the white neutral from the power feed. The ground wire will always hook to the ground and to the switch if it has a ground lug.

When the power is in the light box, wiring lights is a little different. The white wire in the switch leg is going to be used as a hot traveler to the switch (or coming back from the switch). Some electricians will put black tape on the white when it is used like this. The white or black wire coming back from the switch will be hooked to the black or hot for the light. The white or neutral for the light will be hooked to the white/neutral for the power supply. The switch leg will always interrupt the hot power supply. The switch should always be between the power supply and the light.

Wiring lights in a retrofit situation is usually fairly easy. You hook the wires to the new light the same way they were hooked to the old one. Here's a trick, take a digital picture of the wiring before you take the old light down.

wiring-lights-pic1Wiring lights in your home is needed if your fixtures quit working properly. Light sockets, ballasts and other components may wear out. Replacing the defective fixture with a new one may seem like the course of wisdom. New fixtures can be inexpensive and easy to obtain.

OK admit it, you really didn't like that light fixture anyway. Or was it your spouse, 'that light is ugly, let's get a new one'. For whatever reason you want to install a light. What are the concerns? Is it hard? This is something you can do.

For related electrical problems you want to see the articles 'How To Wire a Light Switch', 'Residential House Wiring', 'Ceiling Fan Troubleshooting' and 'Wiring Three Way Switches'. These articles provide additional information and instructions on what to do.

This article will help you decide if this is something you want to attempt. Check out the evaluation sections and see how hard it is. How much could you save if you do it yourself?

Wiring Lights - Information

What Can You Save? - There are no absolutes here. The size and complexity of the fixture matters. A chandelier or ceiling fan is more work that a hall light. Let's say around $75. Could be $50 or it could be $150. You also have to consider the hassle of finding someone and getting them to come out.

How Hard Could It Be? - Wiring lights is not that hard. Sometimes the fixtures have a lot of pieces. Big fixtures can be heavy. These repairs will have a Difficulty Level of: A Bit of Work. These repairs require a Skill Level of: Handyman. For and explanation of the terms in this section, see 'How to Use This Site'.

Check the Simple Things! - Check to bulbs. New bulbs right out of the package can be bad. Did you check the breaker? Loose wires would be the next easy thing. Remember to shut the power off before you mess with the wires.

What Can Go Wrong? - Light fixtures can be quite reasonable to purchase. They can also be quite expensive. Get some help with complex, heavy fixtures. Dropping them will likely ruin it. This is an electrical item, you can get hurt. Shut the power off, tag the breaker and double check the box with a tester.

Troubleshooting Light Fixture Problems


What are the light fixture problems that can be fixed? You are allowed to buy a light new light fixture if you want to. But, is the old one really beyond hope. Don't blame the poor old light fixture if it is just a little worn out. As always, start with the simplest things and then move to the harder ones.

Did you check the bulb? 'Of course I did, dummy', you're saying about now. Try another one, I nearly pulled what little hair I have left for close to an hour once, because a brand new bulb in a package was bad. Did you check the breaker? Make sure it is not tripped.

The next thing to do would be to check for loose connections, both on the fixture and inside the box. Turn the power off first. Tighten any think that seems to be loose. Turn the power back on with the fixture hanging. Check it with a non-contact tester. Do you have power to the fixture? No power to the box? You have a different problem.

Check the switch, do you have power there? With the switch on, still no power to the light? Yes, the switch could be bad. The article 'Wiring a Light Switch', has more information on this subject.

No power anywhere? This is bad, tracing circuits and tracking down basic wiring problems in a home is beyond the scope of this article. See the article 'Basic House Wiring', for some additional insight.

WARNING!! Make Sure the Power is OFF!!! BEFORE You Work on Electrical Devices!!!

Troubleshooting Light Wiring Problems

Wiring Diagrams

There are several ways that light switches can be hooked up inside of the back boxes. For a homeowner, it can be a little daunting to figure out which wire is going to what. Wiring diagrams can help, see the article 'Light Wiring Diagrams' for the available diagrams.

Installing Light Fixtures

When you decide to replace a fixture, you will first need to remove the old one. After you get the old fixture removed, you will need to install the new one. See the article 'Installing a Light Fixture' for information and instructions on what to do with your light fixtures.

Issues With Light Switches

There are different types of light switches that you might have in your home. There are, of course, different problems with each type. See 'Wiring Single Pole Switches' for simple switch problems, 'Wiring Three Way Switches' for lights that have more than one switch that controls them, and 'Wiring Dimmer Switches' for adjustable switches.


How hard a wiring lights project is depends mostly on the fixture you select. Some fixtures are a little hard to get together. I hate to say it, but you probably had to look at the instructions. The wiring is fairly simple.

No question, you probably spent the most time trying to decide which fixture to buy. After that ordeal, putting up the light seemed easy. We hope that your project was successful and you have moved onto more interesting things.

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wiring-a-three-way-switch-pic3Troubleshooting three way switches will involve determining whether the switch is bad or not. You can use a voltage tester to find out.

How Three Way Switches Work

A three way switch will always have power at two poles. One would be for the power

Use a non-contact voltage meter to check and see if you have power to the switch. With a three way switch you always have power to one side or the other. You should get a reading no matter whether the switch is up or down.

Make sure you have checked the bulbs before proceeding. Try the bulbs in another fixture that is working before you automatically assume it is the switch. Does the meter show that you have power to the switch? Yes, then the switch could be bad and need to be replaced. Or the wiring could be loose or corroded.

Turn the power off and take off the cover plate for the switch. Check it with the tester to make sure the power is off. Remove the screws that hold the switch into the box. Pull the switch out and examine the connections.

Are the loose or corroded? Yes, then clean them and tighten them. Turn the power back on and see if this has taken care of the problem. Yes, then it is a job well done.

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