Lamps may look complicated but they are actually simple in design. The lamp cord plugs into the wall, runs up to the body of the lamp, attaches to the lamp socket and once the power is turned on, the electricity flows through the cord and lights the light bulb. According to Handy Man Club of America, it is these items---the plugs, the socket and the cords---that commonly fail in a lamp, and knowing basic lamp repair is a money-saving skill.
Unplug the lamp. Remove the lamp shade and lamp harp from the lamp. The lamp harp removes by squeezing the two sides of the harp toward the centre of the lamp. Pull the harp up and out of the lamp harp base. Move the lamp to a sturdy work surface.
Remove the bottom of the lamp base. Depending on the manufacturer of the lamp, the bottom is attached with screws, covered with felt or heavy paper or snaps on like a lid onto a butter container. If the bottom is covered with felt or heavy paper, carefully peel it off at the base to replace it later.
Remove the exterior socket sleeve off both the sockets. Grasp the sleeve and pull using a slight side-to-side motion, release the sleeve from the socket base, exposing the wiring to the interior socket.
Loosen the copper and silver screws located on the sides of each interior socket and remove the lamp wires from beneath the screws. Discard the old interior socket.
Pull new lamp cord into the lamp by taping a length of new lamp cord to each set of original lamp cords at the socket location. As you pull the original lamp cords from the bottom of the lamp, you are replacing them with new lamp cords. Leave 6 inches of new lamp wire exposed at the socket.
Strip the lamp wires at the socket. Use a utility knife to separate the lamp wires by slicing through the membrane that connects to two lamp wires together. Use wire cutter/strippers to strip a 1/2 inch of insulation off each wire. Be careful not to damage the stranded copper wires inside the insulation when stripping the insulation from the wires.
Identify the hot wire and the neutral wire of the lamp cord by feeling the lamp cords with your fingers. One wire of the lamp cord feels smooth and is the hot wire. The side of the cord that feels as if it has ridges is the neutral side. To help in completing the wiring of the lamp, wrap a small piece of black electrical tape around each smooth wire to identify the hot wire.
Wire the new interior socket by first wrapping the smooth wires around the copper screws on both of the new interior sockets and tighten the screws. Wrap the ridged neutral wires around the silver screws on both interior sockets and tighten the screws. Replace the socket sleeves onto the sockets by pushing them firmly into place.
Remove the old lamp plug and wire. Disconnect the wire connectors holding all the wiring together inside the base of the lamp. Pull all the wires apart and pull the plug wire from the base. Discard all old wires. Add a new plug and lamp wire. Using a prewired lamp cord and plug saves you some time, is just is cost effective as placing a plug on the cord yourself and the ends are already be prestripped. Pull the prewired lamp cord and plug into the lamp base through the opening from which you removed the old lamp plug wire.
Wire the lamp cords from the sockets onto the plug cord. Twist an orange wire connector onto all three hot wires and an orange wire connector onto all three neutral wires. Wrap black electrical tape onto the wires and the connectors, securing the connectors to the wires connecting each set together.
Replace the bottom onto the lamp, lamp harp and the lamp shade.