Once the switch is pulled from the box, check the wiring for condition and proper markings.
- Extend the old switch from the box enough to access the black wires attached to the old switch. Switches always connect to hot (black) wires. In some cases you may find a white wire with the end taped black denoting it is serving as a hot (black) wire. Or you may find a white wire connected to the switch. If that's the case, the prior electrician did not properly mark the wire and it should be marked as a black wire. Wrap the end with black electrical tape after disconnecting.
- Disconnect the old switch by disconnecting the two black wires that connect to the switch.
- You don't do anything with the existing neutral(white) wires or ground (green or bare copper) wires.
