4 Way Switch Wiring Diagrams / How to Wire a Four-Way Switch.

Looking for a guide on how to wire a 4-way switch? This blog is for you.

You can wire a 4 way switch using two pairs of 3-way switches, a four-way switch and an NM cable, or traveler wires if it is conduit wiring.
But you must know how to wire a 3-way switch for the intermediate switch to work.

The 4 way switch wiring allows you to control a light fixture from three or more locations.

They are suitable for stairways or large houses where you want to control a single light from three or more locations.

Four-Way Switch Diagram

An intermediate switch comprises five screw terminals: two travelers, 2 common and one ground screw.

The terminals are usually colored. Travelers with brass color, common with black, and ground or earth with a green color.

Tools and materials required to wire a four way switch

  • Wire stripper
  • 4 in 1 screwdriver
  • Plier
  • Utility knife
  • Voltage tester
  • Electrical tape

Materials

  • Three switches, two 3 ways and a 4-way switch
  • Non-metallic Romex cable
  • Electrical box
  • Bulb
  • Wire nut

How to wire a 4-Way Switch showing all the wiring diagrams

For the 4-way wiring system to work perfectly, you must install the 4-way switch in the middle of the two 3-ways.

Note: Before embarking on electrical wiring or repairs, always turn off your circuit breaker and also wear your protective device to prevent electrical hazards.

4-Way Switch wiring procedures

1. Mount 3 electrical boxes on the switch positions

Mount 3 electrical boxes along the area you want to install the 4 way switch.

But if it is an old house with a wiring system already, look for two three ways, and connect the 4-way switch box in the center.

The switches must not be very close as we only need traveler wires to connect them.

2. Connect to the first three way switch.

The three way switch has 4 screws, one black or common screw, two brass color or traveler screws, and one green screw “earth terminal”.

  • pass a 14 gauge of 3-wire with ground from the center switch box to the first box.
  • Strip and connect the black (hot) wire from the power source to the black screw of the switch
  • Also, connect the black wire from the middle switch to the traveler screw close to the common.
  • Connect the red wire from the 4-way box to the second traveler terminal of the 3 way switch.
  • connect the white or neutral wire from the source to the neutral from the 4 way box.
  • join the brown or earth wires from the voltage source and 4-way box and connect them to the green or earth screw.

3. install and connect the 4 way switch

  • Cut out another 14 gauge 3 wires with ground and feed from the switch in the center to the last three way box.
  • Note the top and bottom of the switch as clearly written on it
  • Strip the wires and connect the red and black wires from the first 3 way circuit to the bottom of the 4-way switch.
  • Connect the black and red wires from the second 3 way box to the top screws of the 4-way switch. Make sure you connect hot wires to common terminals.
  • Connect the two white wires together
  • Also, join the two ground wires and connect them to the earth screw.

4. Connect the last switch to the light fixture

  • Connect the black and red wire from the four way switch to the right and left traveler screws of the last switch
  • Feed in a 14 gauge 2 wire with ground to the switch and connect the black or hot wire to the common terminal.
  • Connect the ground wire from the two wires and switch together
  • Connect the neutral from 14 gauge 3 to 14 gauge 2 wires and tighten the switches.
  • Connect the wires to the lampholder. Black to black, neutral to neutral and ground to ground.

That’s it.

Troubleshooting a 4 way switch

One of the major causes of power failure is a wrong connection. Make sure you wire the circuit properly by following these steps.

  • Connect a four-way switch between two 3-way switches.
  • Four-way switches have five terminals. One earth or ground screw, and four travelers terminals. Make sure you connect it properly by following the above diagram.
  • For a four-way switch to work properly, the three-way switches must be correctly wired. Make sure that you connect the common terminal of one of the 3-way switches to the power source, and the second common to the hot terminal of the load.
  • Make sure that the traveler wires connect to only traveler terminals of the switches. A 4-way switch will only be connected to traveler wires and not neutral or hot wires.
  • Make sure the neutral from the source only connects to the neutral terminal of the load.

Test the switch

Once everything is in order, the electrical system will work. If the issue persists, test the switch.

If you have an existing switch that stopped working, it may have worn out or the terminal screw may have loosened. Check the screw with your screwdriver to make sure it is tight.

You can also test the functionality of the outlet with a multimeter or continuity tester.

To test a three-way switch, connect one of the multimeter probes to the common terminal of the switch, and the other to the traveller terminal.

Flip the switch toggle to view the meter. If it shows any movement, the switch is still good. Otherwise, the switch may have malfunctioned.

To test a four-way switch, connect one probe to one terminal in a pair and the other probe to the traveller terminal in the other pair. Flip the switch toggle to watch for movement.

Move one probe to the other terminal and test again. Still move the second probe to another terminal for testing. If there is movement, the switch is probably good. If not, change the switch.

FAQ

What Colour is the common terminal on a four-way switch?

The common terminal for a four-way switch is usually black.

What is a 4-way switch used for?

A four-way switch is used to control one light fixture from three or more locations

What is the difference between a 3-way and 4-way light switch?

The difference between the two switches is that a 3-way switch has four terminals, while a four-way light switch has five terminals.

Can I use a 3-way switch as a 4-way switch?

You can use a three-way switch when you want to control a light fixture from two different locations. If it is above two locations, use a four-way switch in between the three-way switches.

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About mariaelectricals

Hi, I am Emmanuel Nwankwo, a commercial electrician and the founder of mariaelectricals.com. I established this blog to share my decades of work experience in electrical installations and repairs.