Before you begin anything with a three-way, you must understand that in order for you to have a three-way circuit you must have three-way switches. They are not the same as a regular switch at all. And a four-way is very different again. But that’s on a different page.
When most DIYer’s think of installing a 3 way their brain starts to melt. The fact is it’s very easy. You just need to overcome all those extra wires. Look at the diagram below. You’ll notice we now have travelers. These are the extra ones. But wait, your 3-way switch has two extra screws. So basically, you just need to add those wires to those screws and both switches. Yea it’s that simple.
3-way switch install
However on each 3-way switch, you have a black screw, this is the special one. On the power coming in from the panel, you would connect that black wire to the one black screw. And on the other switch, you would connect the black wire coming from the light to that black screw. The black and red wires in that 14/3 wire would connect to the other two screws.
You connect all white wires together in each box. But of course, the light itself will need that white wire (neutral) to power up. All grounds are tied together and connected to each switch in the box it is in.
Very simple, don’t you agree now.
![2017 NEC - Switch - Neutral Connections [404.2] (14min:30sec)](http://i.ytimg.com/vi/_no-E8ZOkfQ/0.jpg "How to wire a 3-way switch with video 5")
This is very easy and common how to wire a 3-way switch
If you have Lutron dimmer you might want to read this PDF file.
Comments ( 45 )
Thank you very much for your video on how to wire a three way switch. Very helpful
Joe
Always my pleasure
Dominic,great video, my problem is power source is at the light 1st {along with two 2 other wires supplyiny power elsewhere–how do I set up 3 way form light ??
Use my video adding a three way yo a existing one way.
Mr. Dominick,
I understand the basic wiring for a 3-way switch and your video helps to reinforce my understanding. My wife asked me to install new LED fixtures in the hallway. One is on a separate 2-way switch (works fine) and the other is connected to 3-way switches. However, I seem to be getting residual/inductive current; the fixture glows when switched-off. The power seems to be coming into the light and running into the switches. I can’t seem to segregate the residual current to keep the light from glowing. Any ideas?
It sounds like one of the switches is not wired right to where you’re allowing a low voltage to go to the light. A led as you know uses very little electric and just a little will give it some light. First make sure you wired the light correctly. Meaning the hot is on the hot side. Although the wires may be the right colors but it doesn’t mean they are right. Try switching them around maybe. And make sure if you have a ground on the fixture that it is connected.
Hi Dominick, How would I wire 2 lights to 2 3 way switches? I have a light at the top of the stairs and a light at the bottom of the stairs. So i want to put a switch at the bottom of the stairs and at the top of the stairs. Thanks
Each light would just come off of each other. But watch this video. It should help. https://www.askmediy.com/how-to-wire-a-three-way-switch-to-a-existing-single-pole-light-switch-circuit/
My three way switch has the dark screw (common) across from a traveler and the other traveler at the bottom of the switch where the common is in your illustration. Is this a difference in brands of switches?
That would really depend. I’ve seen that before. And how old your switch is. I remember seeing some funky older switches before.
I bought the switch yesterday from Lowes. The switch has “common” stamped on it where the dark screw is, so I know it is not a quality problem from the manufacturer. I will proceed with connecting my High to the dark screw, since you have seen this before. Thank you for your response and video.
Always my pleasure. Let me know how you make out.
Dominick –
Thank you for the diagrams. One minor correction: In the top diagram – the diagram where the switches are labelled S1 and S2 – the wiring to the bulb is backwards. For safety, the hot wire should always go to the tip of the bulb, and the neutral to the threads of the bulb.
MT
Thank you so much for pointing that out. I have fixed that. I didn’t make the picture but I sure fixed that.
Hello
I have stared at your diagram and can’t figure out how to make it work for my set up. In my garage, power comes into a junction box in the middle of the garage. From that junction box a cable goes to the front of the garage where the switch is, another cable goes towards the back of the garage with several outlets daisy chained. These are what our shop lights plug into. The switch turns the outlets on and off. I wanted to add a switch to the back of the garage where the door goes into the house (so I can turn the lights on when i enter the garage from the house). If I replace the current switch to a 3 way, I understand I would need to connect the two 3 way switches with 14-3. It makes sense to me how to wire the switch in the new location, but what about the switch in the old location–it does not have power coming in one way and going to a light. Will I need to connect both black and both whites to the terminals (the ones coming from the junction box and the ones going to the 2nd switch?). I wish I could draw you a diagram, but your contact doesn’t allow me to attach a picture.
Thanks
Yes three ways switches on both ends. There are a few ways to wire a three way. Not just the way I show. This is the comment section of the page you’re on. Use the question section to where you can post pictures. Top right “Questions”
Heya just wanted to give you a brief heads up and let you know a few of the images
aren’t loading properly. I’m not sure why but I think its a linking issue.
I’ve tried it in two different internet browsers
and both show the same results.
Thank you. Funny thing I was changing things on my site the same time you commented on this. They look good to me. I hope they are ok now?
I like your 3 way switch but mu has 3 black wires… How do wire that after getting a 3 way switch and 14-3 wire. My mai. Issue is the wiring of the ols switch. Where am changing it to 3 way switch…thank u for your help.
Old setup up can be a little tricky via chat. There are 9 ways to wire a 3 way. You’ll have to trace each wire to kinda start over.