I'm having a problem trying to replace my bathroom switch....there are 9 separate wires coming out from the wall...1 red, 4 white, 4 black...there is an exhaust fan and then there is a light above the sink and then there is an outlet... I can't seem to figure out which wire's go together and which wires are supposed to have a pigtail in order to put 4 total wires on to the new Switch...can someone please help me???!!! Thank you.

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    We'll almost certainly need a picture for this one. The red, one black, & one white probably go together in one cable. This may be used for a fan/ceiling light combo, or fan/vanity light. Did you take notes or pictures before disconnecting the old switches? – Eric Simpson Nov 23 '19 at 10:53
  • Hello, and welcome to Home Improvement. We'll need more info (at least pictures) before we could help you on this one. And, you should probably take our tour so you'll know how best to participate here. – Daniel Griscom Nov 23 '19 at 13:00
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    DO NOT disconnect and splay out the wires for the photo. – Harper - Reinstate Monica Nov 23 '19 at 16:39
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    Can you post photos of the inside of the box please? And yes, please do not start disconnecting wires willy-nilly! – ThreePhaseEel Nov 23 '19 at 17:02
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    4 wires on the old switch? If you've already taken the old switch out a picture of that's needed too. – NoSparksPlease Nov 23 '19 at 17:16

Here's the trick with electrical wires in junction boxes. There is no color coding. Wires are the colors they are because that's how cables are made.

There is a system and practice for relating wires to functions. However, the information is stored in the the way the wires are connected together already. For instance, in a lamp box with 3 blacks and 3 whites, a wire-nutted group of 2 blacks / 1 white has a specific meaning. There's no need for further documentation; any electrician instantly recognizes what that is, and now knows the function of every wire in the box.

So, that is why we need to see the current, existing relationship of wires in the box to each other.

From time to time, a newbie will pull all of that apart, not realizing. In that case, it's time to call the electrician. We on the Internet cannot possibly discern the function of a bunch of unmarked wires. The electrician will be on-site and will be able to trace out each cable's function.


If you hook all those black and red wires together and all those white wires together separately everything should work.

Now you just need to disconnect the black and red wires that go to the things that you want to stop and put switches in the gap.

don't mess with the wire when they're live, turn the power to that circuit off before experimenting.

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