Most incandescent lamps have a socket, switch, cord and plug. Any one of these parts may wear out and need to be replaced. To check a lamp that doesn't work, test the light bulb, plug the lamp into another receptacle to be sure the receptacle isn't at fault and check the plug and cord for wear.

NOTE: A lamp assembled with rivets instead of nuts and bolts can't be taken apart for repair, so you'll have to replace it.

CAUTION: Before working on any lamp, make sure it's unplugged

There are many types of incandescent light fixtures including wall and ceiling-mounted lights, from single-bulb globes to chandeliers. They are all connected directly to your home's wiring through a recessed ceiling box hidden by the fixture or a decorative canopy. Though instruction here are for repairing and replacing ceiling-mounted fixtures, you'll use the same procedures for wall-mounted styles.

First check the light bulb and then check the circuit and light switch. If the fixture is the problem, the cause may be in the wiring or the socket. Detach the fixture from the ceiling box and check for a loose connection. Tighten if necessary. If the fixture still doesn't work try to replace it or repair it following the instructions found below.

• Shut off the power, remove the bulb and unscrew the cap nuts to free the fixture from the screws on the ceiling box.
• Disconnect the old fixture and strip 1/2 inch off the new wires.
• Wrap the bare ends around the circuit wires and bend over.
• Install wire nuts.
• Carefully push the new fixture onto the screws that hold it to the ceiling box.
• Screw on the cap nuts to secure the fixture and replace the bulb.

• Turn off the power and remove the glass shade.
• Unscrew the fixture screws to free the fixture.
• Unscrew the wire nuts to disconnect the socket wires from the circuit wires.
• Unclip and remove the faulty socket from the fixture.
• Attach the new socket by pushing the wires through and splicing them to the circuit wires with wire nuts.
• Reattach the fixture and replace the cover.

• Shut off the power to the circuit.
• Remove the sleeve, detach the wires from the socket terminal screws and unscrew the socket.
• Remove the cap under the fixture.
• Temporarily tape the new socket wires to the old.
• Detach the old wires from the main cord wires and pull the new wires thorough.
• Screw on the new socket and connect the new wires.
• Remove the old socket wires and attach the new ones to the main cord wires.
• Reassemble the fixture.

The parts of a typical doorbell system are the push button, the door bell, chimes or buzzer and the transformer. The transformer allows the doorbell to operate on low voltage (6 to 24 volts.) Wired into the doorbell circuit at a junction box, it steps down the voltage from the regular 120-volt circuit. When your doorbell doesn't ring, or rings constantly, the problem may lie in one of the parts or in the wires that connect them. NOTE: To diagnose most doorbell problems, you'll need to have the power source connected. But if you're going to work on the transformer or the wires in the junction box, be sure to shut off the power to the circuit. Remember that the input side of the transformer is high voltage, 120 volts.

The first place to look is the source of power. Make sure a fuse or circuit breaker hasn't blown or tripped. Once you're certain that the 120-volt side of the transformer is getting power, shut off the power and tighten all wire connections. Turn the power back on and check the low-voltage side, following the steps below to find the source of the trouble.

• Use a volt-ohm meter. If the transformer is working correctly, the meter reading should match the secondary voltage (6 to 24 volts) marked on the transformer or bell.
• Set the voltage range on the meter to 120 volts AC and measure the voltage between the two low-voltage terminals on the transformer.
• If the meter reads significantly higher than the correct secondary voltage, the transformer is defective and should be replaced.
• If the reading is close to the correct secondary voltage, test again by setting the voltage range on the meter to a lower value. If the new reading doesn't agree with the voltage marked on the transformer or bell, replace the transformer.

• Disconnect the two wires connected to the button and short them by touching their bare ends together.
• If this makes the bell ring, the push button is defective and should be replaced.
• If the bell doesn't ring, the problem is either in the bell or chime mechanism or in the wiring.

• Have a helper push the doorbell button while you listen to the bell. If it makes a buzzing or humming noise, it may be gummed up with dirt.
• Check the mechanism and clean it as necessary using fine-grade sandpaper to remove corrosion form any contacts.
• If the bell still hums or buzzes after cleaning, replace it.
• If the bell doesn't make any noise at all when the button is pushed, disconnect the bell and, using new wire, hook it up directly to the transformer. If it works, inspect the old wiring. If it doesn't, replace it.

• Examine the wiring for breaks or frayed insulation that may be causing the wires to short out.
• Repair any breaks and wrap the repairs with electrician's tape.

If a doorbell rings constantly, either the button is stuck or the wires going to the button are shorted together. To test follow these steps:

• Test the button by turning off the power to the transformer.
• Remove the button from the door frame and disconnect one of the two wires connected to it.
• Turn the power back on. If the bell doesn't ring, the button should be replaced. If the bell rings, the problem is a short between the two wires.
• With the power turned off, examine the wires for frayed insulation or bare wires rubbing together.
• Use electrician's tape to wrap them where necessary.
• If you can't find the short, replace the wires.

• To remove the socket, loosen the socket shell by pushing in where the word "PRESS" is embossed.
• Lift off the shell and insulating sleeve.
• Unfasten the wires from the socket terminal screws.
• Inspect the cord insulation, if it's okay, test the socket and replace if necessary. If it's faulty, continue with these steps.
• Replace a faulty cord by untying the knot.
• Splice the new cord to the old by twisting the bare ends of the wires together and taping them. Pull both cords through.
• Detach the old cord.
• Split the new cord to 2-1/2 inches from the end.
• Tie an Underwriter's knot by making two loops and passing the loose wire ends through the loops. Pull the knot snug.
• Strip 1/2 to 3/4 inch of insulation from the ends of the wires.
• Wrap one wire clockwise around each socket terminal screw and tighten the screws.
• To reattach the socket, push the insulating sleeve over the socket and push in the shell until you hear it click into place.
• Attach a plug to the cord.

• Unplug the damaged cord and unscrew the other end form the terminal screws on the appliance.
• Be sure you get an exact replacement for the damaged cord and plug.
• Connect the new pigtail cord to the terminal screws on the appliance.
• If the wires in the cord and the screws on the appliance are color-coded, attach the wires to the terminal screws of the same color (black to black, white to white, red to red.)
• If either the pigtail cord of the appliance terminal screws are not color-coded, first attach the center wire of the pigtail to the center terminal screw on the appliance.
• Connect the remaining wires to the remaining terminal screws.
• Plug in the new cord.

• Many old-style plugs with terminal screws have a removable insulating disc covering the terminals and wires. The National Electrical Code now requires "dead-front" lugs that have a rigid insulating barrier.
• To replace a plug, cut off the old one plus at least an inch of cord. For plugs with terminal screws, split the cord insulation to separate the wires and strip the insulation from the ends.

In terminal screws the wires are attached to screws inside the plug body. To replace:

• Unscrew and remove the new plug's insulating barrier.
• Using a utility knife, split the end of the cord to separate the wires.
• Push the cord through the plug body.
• Make two loops with the wires.
• Pass the loose ends of the wires through the loops and pull tightly to form an Underwriter's knot (this prevents strain on the terminal screws.)
• Strip 1/2 to 3/4 inch of insulation off the wire ends being careful not to nick the wires.
• Unscrew the terminal screws on the barrier to allow space for the wires.
• Form loops on each wire and wrap the wires clockwise 3/4 way around the screws.
• Tighten the screws and trim the excess wire.
• Reattach the barrier.

• Unscrew the insulating barrier.
• Push stripped wires through the plug body into the correct terminal slots.
• Attach the wires to the terminal screws as follows: white neutral wire to silver screw, black hot wire to brass screw and green grounding wire to green terminal screw.
• Tighten the terminal screws and reassemble the plug.

• Push the cord (don't strip it) through the shell and into the terminal block.
• Squeeze the prongs together to grip the cord.
• Slide into the shell.

• Unscrew the plug shell.
• Feed the cord through the spring guard.
• Strip the wire ends and wrap them clockwise around the terminal screws.
• Tighten and reassemble the plug