Help with 4 way switch
#1
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Help with 4 way switch
Can someone help me understand the wiring diagram for a 4 way switch where the source and fixture originate in the first switch. Long sorry short, I have 2 fixtures and 4 switches that I replaced with new decora rockers from Leviton and I just found out I didn’t wire it properly when I replaced them.
When I originally swapped out the switches, I didn’t have a wiring diagram; now I do but I still have questions (for reference, I have a second 4 way switch between my two 3 ways).
My question is, does it matter which traveler screw the red and black wires connect to at the last 3 way (left side in picture). To dumb down my question, does red need to go on a specific side? When I get to my first 4 way, does it matter which “in” traveler screw and “out” traveler screw the colors are connected to (i.e. do both reds have to go on one side and both black on the other?)? I believe in my case with the Leviton’s my ins are on one side and the outs are on another so the question would be do the black wires need to go at the top (or bottom) and match on the out side?
By the way the light switches function, I’m guessing I screwed up at one of the 4 ways but I can’t figure out how. If the answer to my question is that they do need to remain constant, can someone explain why? I’m an electrical newbie and am also looking to learn in addition to fixing my light!
thanks in advance!
When I originally swapped out the switches, I didn’t have a wiring diagram; now I do but I still have questions (for reference, I have a second 4 way switch between my two 3 ways).
My question is, does it matter which traveler screw the red and black wires connect to at the last 3 way (left side in picture). To dumb down my question, does red need to go on a specific side? When I get to my first 4 way, does it matter which “in” traveler screw and “out” traveler screw the colors are connected to (i.e. do both reds have to go on one side and both black on the other?)? I believe in my case with the Leviton’s my ins are on one side and the outs are on another so the question would be do the black wires need to go at the top (or bottom) and match on the out side?
By the way the light switches function, I’m guessing I screwed up at one of the 4 ways but I can’t figure out how. If the answer to my question is that they do need to remain constant, can someone explain why? I’m an electrical newbie and am also looking to learn in addition to fixing my light!
thanks in advance!
#2
My question is, does it matter which traveler screw the red and black wires connect to at the last 3 way (left side in picture
When I get to my first 4 way, does it matter which “in” traveler screw and “out” traveler screw the colors are connected to (i.e. do both reds have to go on one side and both black on the other?)?
It also doesn't matter which wire from the cable goes on which screw of the pair.
It's possible the screw colours will black and gold instead of gold and silver. Just remember to work with the pairs.
#3
My question is, does it matter which traveler screw the red and black wires connect to at the last 3 way (left side in picture).
When I get to my first 4 way, does it matter which “in” traveler screw and “out” traveler screw the colors are connected
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Hi guys, so I opened up the switches and the gang of wires from the 3 wire leading from the originating box to the first 4 way uses the white wire instead of the black. It’s like that all the way through. Is this a problem? When I changed the switches I did not mess with the wires that were already capped meaning the house has been like that for 20 years.
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hand sketched layout
I was confident I swapped my ins and outs on one of my 4 ways so I disconnected both and did a voltage check on them. #2 had power first so I connected the powered gang to the in connections of the first 4 way and used the second gang of wires for the out. I repeated the steps on the second 4 way. I updated my diagram assuming the next switch with power would be the next in line.
I think my wiring is correct but switch #3 won’t work unless switch #2 is turned off and when switch #3 is turned on, switch #2 will not turn off the light when toggled (same issue I had before all my efforts).
Can anyone tell me what I’m doing wrong before I pull my hair out?
I was confident I swapped my ins and outs on one of my 4 ways so I disconnected both and did a voltage check on them. #2 had power first so I connected the powered gang to the in connections of the first 4 way and used the second gang of wires for the out. I repeated the steps on the second 4 way. I updated my diagram assuming the next switch with power would be the next in line.
I think my wiring is correct but switch #3 won’t work unless switch #2 is turned off and when switch #3 is turned on, switch #2 will not turn off the light when toggled (same issue I had before all my efforts).
Can anyone tell me what I’m doing wrong before I pull my hair out?
Last edited by mills5937; 07-22-19 at 07:36 PM. Reason: Corrected picture link
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4 way
I just had this problem last week on a leviton decora 4 way. Their pairs are on the sides instead of top and bottom. So at your first switch has 120v power and a switched leg to the light, this means at the "end" of the 4,5,6 way switch will be a dead end three-way. At the first box with the power, the white on the three wire will be wire nut together and packed away. What that means is the switches are being fed with the white wire is the common at the dead end three way switch. Make sure the whites are together at all the 4 way locations. Now, at the first switch again there's the two travelers and your other wire going to the light, this is the other common. Now, the black and red from one 3 wire go on one side and the black and red wires from the other 3 wire go on the other side. Do that at all your 4 way locations and it should work just fine. Dont forget to hook up your grounds of course. Another possibility is that one of your 4 way switches could be a double pole single throw switch instead. Look at your switches and confirm that none of them say on or off on them...
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@sparknock - I posted a diagram I drew in the post above. Can you look and tell me what you think? I believe I’ve done what you said and am still having issues.
How would I know if my switch is double pole single throw?
How would I know if my switch is double pole single throw?
#11
There is no in and out but I kept the same naming you used. You are assuming that your switch is wired like the left diagram. However, some 4w switches are wired like the right diagram. The correct wiring is always listed on the box.

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Wanted to provide you an update. I fixed the issue, turns out one of the 4 way switches went bad. I was able to prove it out by wiring the two three way switches together, checking the function, then adding a 4 way in and repeating the process. Through this, I found the 4 way that needed replaced. Apparently it’s fairly common but I’m glad I fixed it before I had to spend the money on an electrician. Thanks for everyone’s help!