How to Change a Two Way Light Switch
- 1). Turn off the power to the light circuit at the corresponding circuit breaker. Turn on the switch that will be replaced. If the light fixture comes on, the wrong breaker has been turned off. Go back to the breaker box and turn off the correct breaker.
- 2). Remove the switch's faceplate with a screwdriver. Remove the screws holding the switch to the switch box. Pull out the switch. Loosen the two terminal screws on the back of the switch, and remove the two black wires. Loosen the switch's ground screw and remove the ground wire. Note that the two white wires are joined together with a wire nut in the back of the box.
- 3). Cut off the hook-shaped bare ends of all three wires using wire cutters. Strip off 1/2 inch of insulation from the ends of the black wires, using wire strippers. Bend the ends of all three wires into a hook shape, using long-nose pliers.
- 4). Attach one black wire to either terminal screw on the new switch. Attach the other black wire to the remaining terminal screw. Tighten the screws to the wires. Attach the ground wire to the ground screw, and tighten the screw to the wire.
- 5). Push the wires into the back of the box, and secure the switch to the box with the two screws. Place the faceplate over the front of the switch and use the two screws to secure it in position. Turn on the power at the circuit breaker.
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