3 Way and 4 Way Wiring for Multiple Lights

The wiring diagrams on this page illustrate connecting multiple light fixture in 3 way and 4 way switch circuits. Also included are receptacle and light fixture combination circuits. Check below for more details about these circuits, wiring and troubleshooting.

Wiring Multiple Lights Between 3 Way Switches

In this multiple light circuit, two fixtures are shown but more can be added by duplicating the wiring between the lights, for each one added. Note that the ground wire is not used in one of the two–conductor cables between the light fixtures. This wire can be capped or taped and folded to the back of the box out of the way.

Wiring Multiple Lights Before 3 Way Switches

This diagram illustrates wiring multiple lights and the source before the 3 ways. As with the other diagrams on this page, more lights can be added by duplicating the wiring arrangement between the fixtures.

Wiring Multiple Lights with a 4 Way Switch

This diagram shows the wiring for a 4 way circuit with the source and lights coming before the switches. As with all these circuits, the 4 way must be wired between the two 3 ways.

Wiring Multiple Lights with a 4 Way Switch, Lights Center

This 4 way wiring illustrates the source coming before the switches and the light between. The 4 way can be placed between, or on either side of the light fixtures, as long as it occurs between the 3 ways the circuit will work.

Wiring a Light and Receptacle

This wiring diagram illustrates the connections for 3 way switches to control a receptacle added to a lighting circuit. The hot source is connected to the receptacle and the common on one of the switches. The second common is connected to the hot on the light fixture. The neutral is connected to the receptacle and the fixture.

This diagram is similar to the one above but both the light and receptacle are wired after the two 3 way switches.

A 4 way switch must be wired between two 3 ways as shown in the diagrams on this page. A 4 way has five connections, one ground and 4 circuit terminals divided into two matching pairs, sometimes called the input and the output. The terminal pairs may be different colors or they may be labeled to distinguish them from each other. Each pair of terminals should be wired to the traveler wires from one of the 3 ways. The travelers can be wired to either terminal in a pair but don't mix up the pairs or the circuit won't work properly.

Three way switches have 3 terminals to carry circuit electricity and one terminal for a ground wire. Of the three circuit terminals, one is called the common and the other two are known as travelers. The common terminal may be labeled and is usually a different color than the traveler terminals. Depending on the manufacturer, the travelers may be on opposite sides of the switch or the two terminals may be on the same side. In any case, the common terminal will be distinguished from the travelers in some way.

The common terminals will always be connected to a hot wire, either the hot source or the device hot. These connections can be reverse if it's more convenient, as long as one of the 3 way switch common terminals connects to the hot source and the other one connects to the hot on the load, these circuits will work properly. The traveler terminals will be connected from switch to switch. Travelers never connect to a device load or to a source wire. It doesn't matter which traveler terminals are used for which traveler wire, reversing them should make no difference.

About Wiring

The wiring diagrams on this page illustrate 15 amp circuits using 14/3 cable between the switches and 14/2 cable to the light fixtures. Existing household wiring used for lighting and receptacles may be on 15 or 20 amps circuits. To use this wiring in 20 amp circuits use 12 awg cable and devices rated at 20 amps.

To avoid confusion the white cable wire should be marked with black electrical tape when splicing it to carry current. Ground wires should be spliced with a short piece of wire and connected to each device. If the light fixture box has a metal grounding terminal the ground wire should be connected there.

All these diagrams have been tested in real life circuits but because of variable factors in existing wiring the examples displayed here may not work in every instance. To avoid problems make sure the hot wire from the source is connect to the common on one of the 3 ways and the hot wire to the fixture is connected to the common terminal on the other one. Aside from the ground wire, only traveler wires will be connected to a 4 way. If after wiring, you experience problems with the circuit, switching the traveler wires will most likely resolve the issue.