Log in

View Full Version : Probably a stupid 4-way wall switch question, but . . .



Ramsker
02-12-2022, 22:05
Mom calls to tell me she has a light switch that's broken (late 80's construction home). I go over to take a look and the switch is not working well. The plastic switch itself must have something broken inside and it doesn't function right. It gets stuck and has to be forced to work. Existing switch is a 4-way switch. 2 red wires connected to bottom terminals and 2 black wires connected to top terminals. I picked up a new 4-way switch at the hardware store thinking this was an easy fix.

This is probably a dumb question, but before I do anything I'm assuming I just wire the new switch the same way . . . same black wires to same top terminals and same red wires to same bottom terminals on new switch? Nothing has changed in 4-way switch technology over the years for some odd reason? Pics below for reference.

https://i.imgur.com/DbnivCr.jpg

https://i.imgur.com/zuEKfnR.jpg

sandman76
02-12-2022, 22:28
One set of black/red (travellers) to each set of colored screws. Usually black screws and brass screws. Make sure each set is from the same cable.

eddiememphis
02-13-2022, 09:27
Sandman is correct. Same color wires on same color screws. In your case, both blacks on both blacks, both reds on both brass. The whites in the box should be wire nutted together. The grounds wire nutted together with a pigtail coming off for the green screw on the switch.

When you put in the new one, don't use the push in holes if you can avoid it. It only makes contact in a couple places. Wire wrapped around the screws is a much better connection.

Ramsker
02-13-2022, 10:07
Sandman is correct. Same color wires on same color screws. In your case, both blacks on both blacks, both reds on both brass. The whites in the box should be wire nutted together. The grounds wire nutted together with a pigtail coming off for the green screw on the switch.

When you put in the new one, don't use the push in holes if you can avoid it. It only makes contact in a couple places. Wire wrapped around the screws is a much better connection.

New switch only has the terminal screws, so that's easy enough. It has 2 black screws on the bottom of the switch (marked input) where the ground screw is and 2 brass on the top (marked output). Sounds like whoever did the wiring originally just put both reds on the bottom instead of on the top?

Thanks for the responses, by the way!

eddiememphis
02-13-2022, 10:19
Color doesn't matter as long as the same color is on the opposite side, same color terminals. Whether you call it by screw color or top/ bottom.

Since a 4 way isn't a traditional on/off, you can rotate it 180 degrees. So there isn't really a top or bottom.

FoxtArt
02-13-2022, 13:21
Uncommon side note:

Also if it doesn't work (new switch) test all outlets in the room and any adjoining room. If any don't work the problem is likely not at the switch. Pull any outlets that don't work and check the connections. I've seen them (randomly....) disconnect before from crap build jobs. Even 30+ years later. Not sure how that can happen, but that will make upstream light switches look like they failed (unless you test with a voltmeter there and realize there is no power).

ETA:
Lastly, if it still doesn't work, it could be the light receptacle. Check connections there too.

And make sure you find the proper breaker - use a screwdriver to bridge between hot and ground before doing your work. Every now and then it'll surprise you and be hot :P

I've been shocked way too much with 110, it's not all that dangerous especially if you are diligent to work in a way where a short goes through one hand only (one-hand rule while wiring, don't be holding a conductive receptacle with both hands). It'll still make you swear though.

Ramsker
02-13-2022, 13:33
Uncommon side note:

Also if it doesn't work (new switch) test all outlets in the room and any adjoining room. If any don't work the problem is likely not at the switch. Pull any outlets that don't work and check the connections. I've seen them (randomly....) disconnect before from crap build jobs. Even 30+ years later. Not sure how that can happen, but that will make upstream light switches look like they failed (unless you test with a voltmeter there and realize there is no power).

ETA:
Lastly, if it still doesn't work, it could be the light receptacle. Check connections there too.

And make sure you find the proper breaker - use a screwdriver to bridge between hot and ground before doing your work. Every now and then it'll surprise you and be hot :P

I've been shocked way too much with 110, it's not all that dangerous especially if you are diligent to work in a way where a short goes through one hand only (one-hand rule while wiring, don't be holding a conductive receptacle with both hands). It'll still make you swear though.

Yeah, I've had a few "buzzes" in my life. My favorite one was when we were doing some kitchen remodeling and I wanted to replace the outlets on each end of our island with a different color. Went outside and found the breaker and turned it off . . . then replaced the outlet on one end. Walked around to the other end and went to pull out the other outlet to swap it out . . . it was on a different circuit. Got a nice little surprise. My fault for assuming and not testing it, but I haven't made that mistake again.

It's definitely this switch that is bad. The other ones work and the light works. This one "works", but it just doesn't move up/down very well anymore and sometimes won't move past half-way. Must be something busted off inside that sticks.

00tec
02-13-2022, 13:37
Pffft... if you don't put an arc on at least 1 tool while messing with electricity, you ain't doing it right.