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I have two switches that control one light. I would like to close one of the switches, so that the light is only turned on and off by one of them. I removed the light switch from one of them (pictured), but now the other light switch won't turn on the light (also pictured with connected wires. Do I need to close the circuit somehow by connecting the wires from the old switch?

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    Are you able to run a temporary wire between the two switch locations, and a low voltage light bulb, and a battery ? Start with a basic continuity test to identify the ends of each wire, and which go where. And then label them clearly. – Criggie Jul 21 at 0:48
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    Are you sure there were not three switches that controlled the fixture in question? The fact that there are four traveler wires (and they are all curled like they were on a screw terminal and not wire nutted) suggests strongly that the removed switch was a four-way. – smitelli Jul 21 at 17:08
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This is what happens when you randomly tear stuff off the wall without taking pix first. I'm guessing you assume the wire colors are meaningful in some way; colors mean less than than you think, and less than nothing at all in 3-way circuits. That stinks, so get some yellow electrical tape; we need to make colors meaningful.

Looking at the 3-way switch still wired, it appears a black wire is on the black screw (coincidentally). That means the two brass screws are red and white -- those are travelers and mark them both yellow with tape.

On 3-way switches, travelers go to brass screws. That's what you must remember. Switch manufacturers randomize the location of black and brass screws on every model of switch.

The other switch, we don't know. However, 90% of the same time, the travelers here are simply the other end of the same cable, so they'll be the same colors -- red and white in this case.

That's tricky because there are two reds, but hold on, didja catch that? The travelers are in the same cable. So follow the white wire back, see which red wire joins it in the same cable, and voila - those two are your travelers. Mark them yellow.

Whoo! We now have the 2 travelers identified. Now everything gets easy.

There were 3 wires (besides ground) going to the old switch. Pick one traveler at random and cap it off. You will need tape to hold a wire nut on a single wire. Join the remaining two wires with a wire nut, but don't tape it - if it won't hold by itself, it's a bad connection and it will arc and start a fire.

At that point, the switch will work in one position. If it works in the "down" position, flip the switch over when you install it.

A few more matters

You may notice you can go into 99% of rooms and find the light switch immediately. That works because the Building Codes require you have switches in certain locations. You are not allowed to have "secret switches" that only you know how to turn on. This protects both your invited guests and first responders: so the EMT can see to save your life, and the cop can see that's a computer mouse not a gun in your son's hand. Make sure that your switch removal does not violate the building codes or make it hard (for visitors) to get a light switched on in that room.

Also, I must warn you that you cannot bury electrical junction boxes. You currently have a blank cover there; that must stay there forever until you run a new cable which bypasses this box, and remove those cables. Further, you may want to leave it as a house feature, in case the new owner wants to restore that switch. (or the pre-sale inspection reveals the switch is mandatory).

  • "At the dead switch, join the remaining wire to one of the travelers with a wire-nut. Cap off the other wire." What is the remaining wire? I've identified both sets of traveler wires. Do I connect one wire from each pair to each of the black wires? – Jonas Jul 20 at 20:14
  • @Jonas Presumably there were 3 wires going to the old switch - 2 travelers and something else (a "remaining" wire). It's either an always-hot or switched-hot but it doesn't matter. – Harper Jul 20 at 20:44
  • Is it common to use a white wire as a traveler like that? I always thought it was against code to use white as anything other than neutral unless it was marked with tape – Max Ehrlich Jul 21 at 13:07
  • @MaxEhrlich Correct. This is why I say "mark travelers with yellow tape". Gray and white are neutral colors, green and yellow-green are ground. All others are hot colors including yellow. – Harper Jul 21 at 13:37
  • "So follow the white wire back, see which red wire joins it, ..." Looking at the OP's photo, it seems to me there are two white wires, not one. And I would bet that each of them shares a cable with one of the red wires. It really looks a lot like it may have been a 4-way switch, not a 3-way. – Ilmari Karonen Jul 21 at 21:15
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enter image description here

Here's a quick diagram. Switch 1 in the first box has 3 wires, and so does switch 2. In this diagram sw1 is "up" and sw2 is "down" so no current flows left to right.

Just join the "down" wire on sw2 (the one you don't want) with the wire that proceeds to the light (or from power), disconnect or remove the other "up" wire, and then sw1 is in complete control of on or off - it's like you've "frozen" sw2 in one state.

This answer doesn't address colors, because (especially on switches like this) the wires are not always consistent. But if you can visualize what's happening, you can work your way through it. Have fun, and be safe!

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    I went ahead and subbed my standard 3-way drawing; if you don't like it, feel free to revert. – Harper Jul 20 at 17:42
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    haha, hope at least a few people look at the original ASCII character drawing I made to appreciate my software development skills ;) – Oliver Williams Jul 21 at 18:24
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Ok first off I hope you put wire nuts on the ends of the wires when you removed the switch. Leaving exposed live wires in a box is extremely dangerous as a shorting, fire and risk to life hazard.

What you are trying to do is to convert a 3 way switch to a standard 2 way switch. This isn't necessarily straight forward because 3 way switches use special wiring called carrier lines to enable two switches to control one light.

IF the switch you want to remove only has 1 line coming to it consisting of 3 wires (white, black and red (plus a ground which we don't count) then you can do it pretty easily.

This is based on your pictures and the fact that your black wire is connected to the black (common) screw

  1. Disable power to the line at the breaker/fuse box.
  2. As you did, remove the switch in question.
  3. Connect the black (common) line to either the red OR white line but not both.
  4. Put caps over the tied together lines, and the leftover line.
  5. Tuck the wires back into the box
  6. Enable the circuit and test the change using the other switch
  • So I pulled out the wires to get a better look and its two red wires, two white wires, a copper ground wire, and two black wires (currently spliced). Not sure what that means... – Jonas Jul 20 at 15:50
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Looks like a 4-way switch location at pic with single box location. blacks spiced in wire nuts and red and black travelers. I am and I suggest to call an electrician. The hardest part of working on electric is perceiving your known and unknown hazards.

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    Hello, and welcome to Home Improvement. There are three other answers which instruct and inform, which is much more helpful than just saying "call a pro." And, you should probably take our tour so you'll know how best to contribute here. – Daniel Griscom Jul 21 at 12:40
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This would be easier to answer had you shown us a picture of how the conductors were connected to the switch before you removed it. Since we don't have that, we have to guess, which is inherently dangerous. I will go ahead and guess, but that doesn't mean you should act on my guess, because it could be perilous if I have guessed incorrectly. Also, you should take safety measure that others have mentioned, including not leaving uncapped wires in the wall and installing a blank cover plate (not drywall) over the electrical box.

If you really have two switches (not three) that control that light, then it's puzzling because there are more red conductors than I would expect. It's also weird that there appears to be only one ground wire (the bare one).

Presumably one of the black conductors is hot coming into the box. The other black conductor goes to the switch you have shown us. The red conductor and the white conductor coming back from that switch are the "travelers". But what are the remaining red and white conductors?

The simplest explanation would be that the switch you have removed was a 4-way switch, and that the remaining red and white conductors are the travelers headed the other way. If this is the case, then you want to emulate what a 4-way switch would be doing if it were still there and it were stuck in a fixed position, which would be to wire-nut together a traveler going one way with a traveler going the other way (and then again for the other pair). It would work either white+white&red+red or white-red&red-white, but I think white+white&red+red is more aesthetically pleasing.

But that's only the simplest explanation. If it's really something else, then all bets are off. Stay safe.

  • Maybe there were originally three switches, and some previous tenant did the same thing that OP is now trying to do and removed one of them? In any case, I agree that it looks as if the switch that the OP removed was probably a 4-way. And also with your last paragraph; at this point, the OP really needs to double-check every wire to find out where they go and how the whole circuit is (or was) supposed to work (or hire an electrician to do it for them). – Ilmari Karonen Jul 21 at 21:26
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The picture with the wires showing where there are 2 red and 2 white wire look like you had a 4-way switch there meaning there is actually 3 locations where the switches shut off the lights. If you splice together the 2 whites under one wirenut and the 2 red under another wire nut that will take the switch out of the picture. Then you can go to the other location and splice the wire that is on the black screw with one of the wires that is on the screw above either the red traveler or the white traveler. That will take the other switch out of the picture also leaving the last 3-way there.

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It would appear that was the location of the 4-way switch. Twist the red wires and wire nut. Twist the white wires and wire nut. Stuff them back into the box and use a blank cover. There will be 2 other switches that now control the light. Open both locations and the one with just one set of wires going to it is the dead end side. From that point you can only control the light from the other location.

To save you house and possibly your life, hire an electrician.

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    Hello, and welcome to Home Improvement. "Hire a pro" answers aren't that helpful here, unless it's an egregious circumstance. And, you should probably take our tour so you'll know how best to contribute here. – Daniel Griscom Jul 22 at 11:23

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