3-Way Switch Wiring Diagram Variation #3 : Electrical Online Wiring diagram for a 3-way switch, one of the many wiring diagrams showing different methods of wiring a three way switch circuit. This electrical wiring diagram shows power into light switch Box #1 – wire to light from switch box #1, and from switch box #1 to three-way light switch box #2. Wiring a 3-Way Switch - how-to-wire-it Each 3-way switch in these examples are controlling the power source to the same load. When wiring a 3-way switch circuit, we will be using a 3-wire cable known as romex coming from the source (such as the breaker box). Then a 4-wire cable going between the two 3-way switches and then a 3-wire cable going from the switches to the load. Find the correct wiring for a 3-way switch in 2-minutes Click to view on Bing2:07How to determine the correct wires to attach to a 3-way switch when the wire and screw terminal color code is not (load/hot) screw in a 3-way switch in 2-minutes! - Duration: 1:47. MarVistaCat How To Troubleshoot Light Switches and Light Switch Author: MarVistaCatViews: 266K 3 Way Switch Wiring Diagrams - Do-it-yourself-help 3 Way Switch Wiring with Light First. In this diagram the source for the circuit is at the light fixture and the two switches come after. Two-wire cable runs from the light to Three Way Smart Switch Wiring - Smart Home Czar How to Wire a Smart Three-Way Switch. With this basic understanding of how the smart three-way switch works, wiring a smart-three way switch should make more sense. The GE smart three-way switch comes with detailed instructions and a wiring diagram that is accurate. But it suffers a bit from too much information.