Re-Wire 3 Switches to 2


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Old 04-27-15, 08:58 AM
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Re-Wire 3 Switches to 2

Hoping someone can help me figure out the wiring in my garage. I have 3 switches in my switch box: a single pole switch on the left which controls recessed lights outside my garage door, and 2 switches on the right which I'm not sure what they do. I believe one of them controls a driveway flood light, which is how I found this wiring because I replaced the light and found there was no power coming to it at all.

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So when I opened the box, this is what I found.

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From left to right, the 2nd and 4th cables are the ones bringing power in. The 1st cable is going to the recessed lights, which work fine. The 3rd cable is the one I think goes to the flood light, but my voltage tester can't detect any power when flipping any switches.

If anyone can help me understand this wiring I would be grateful. If I look at the 4th cable on the right (bringing power in), the black goes to the wire nut on the left. This wire nut also has the red from the incoming power 2nd cable, and a pigtail which goes to the top terminal of the switch on the top right. This same terminal has a "jumper" black wire which goes to the single pole switch and brings power to that. The top black wire on the single pole goes to the cable for the recessed lights.

Moving to the 2nd cable which also brings in power, the red as I said is wire-nutted, and I see the black and neutral connected to the top switch terminals on the right. Below them is the neutral and black for the cable going out to I think the flood light. This is the cable that shows no voltage when the light is switched.

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By the looks of it, this has been around for a while and I'm wary of changing this because I guess it was working fine at one point (we just moved in). But what I'd like to do is simply have 2 single pole switches in the box and each one controls a set of lights. If this is a 3-way switch I can't find another switch in the garage, or a nearby room, which would be the other 3-way switch.

Any harm in re-doing this in a much simpler way? Cap off the reds, wire nut the neutrals together, and use 2 single pole switches in the gang box? Each switch would be responsible for one set of lights. Thanks for any help.
 
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Old 04-27-15, 09:40 AM
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The double switch looks like 2) three way switches. Did you try following the cables. The likeliest location for matching switches would be inside the house.
 
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Old 04-27-15, 09:41 AM
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I don't think that the white wires connected to the switches are neutrals nor do I think that there are two hot leads from the panel box. It looks like there is a jumper from the single 2 pole switch. How many breakers control that switch box?
 
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Old 04-27-15, 09:57 AM
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The double switch looks like 2) three way switches. Did you try following the cables. The likeliest location for matching switches would be inside the house.
That's what I thought but I can't find the other matching switches, and frankly, even if there are matching switches I don't care if I lose them. Meaning, I'd be fine with converting these to single pole. But what stumps me is that the 3rd cable shows no voltage when any of the switches are moved. Would I be better off getting an exact replacement for the 2 three way switch and rewiring exactly as it is?
 
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Old 04-27-15, 10:00 AM
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I don't think that the white wires connected to the switches are neutrals nor do I think that there are two hot leads from the panel box. It looks like there is a jumper from the single 2 pole switch. How many breakers control that switch box?
Yes, there is a jumper from the single pole switch to the 3 way switch. My voltage tester indicates that the 2nd and 4th cables are hot leads though. They are controlled by 1 breaker which controls the interior lights in the garage as well.
 
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Old 04-27-15, 10:11 AM
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My voltage tester indicates that the 2nd and 4th cables are hot leads though
If you mean a non contact tester it is not really a voltage tester*. You don't really know what us hot. To test for voltage you have to use a multimeter, preferably analog (or test light or solenoid tester). You test by resuming to ground or a known good neutral, preferably the neutral in the same cable.

*Contact testers react to the presence of a magnetic field which may or may not be caused by usable voltage.
 
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Old 04-27-15, 11:15 AM
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If you mean a non contact tester it is not really a voltage tester*. You don't really know what us hot. To test for voltage you have to use a multimeter, preferably analog (or test light or solenoid tester). You test by resuming to ground or a known good neutral, preferably the neutral in the same cable.

*Contact testers react to the presence of a magnetic field which may or may not be caused by usable voltage.
You're absolutely right it's a non-contact tester. I guess I feel a decent degree of certainty with it because it reliably shows the first cable as hot only when switched by the single pole, and I try to test the cables at a point where there is some separation from other cables, which is how I came to the determination that cables 2 and 4 are providing power, and there's no power in cable 3 at all.
 
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Old 04-27-15, 11:35 AM
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Until you use a reliable test method to determine which wire is hot it will be hard to help you.

An analog (not digital) multimeter will cost less than $15 and if you have a kid I'm sure (s)he'd enjoy playing with that non contact tester.
 
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Old 04-27-15, 11:51 AM
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Until you use a reliable test method to determine which wire is hot it will be hard to help you.

An analog (not digital) multimeter will cost less than $15 and if you have a kid I'm sure (s)he'd enjoy playing with that non contact tester.
Point taken. I've actually got a multimeter somewhere so let me dust it off and get back to you with the results.
 
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Old 04-27-15, 05:57 PM
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If only one breaker controls the switch box then the other switches are getting juice from the jumper or there is a 3 way switch somewhere. Disconnect the jumper. Then see what's hot. As Ray said, until you determine what's hot & when it's hot, there is no way to help.
 
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Old 05-04-15, 08:40 AM
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OK, I finally got around to using my multimeter to test which wires are hot. Going from left to right, this is what I believe the wires are for. I've marked the voltage readings for anything greater than 0 v.

1. 14/2 cable that connects to outdoor light fixture. In the original wiring this was controlled by a single pole switch.
2. 14/3 cable that controls the garage overhead and works with another switch on the other side.
3. 14/3 cable that I cannot seem to locate where it's coming from or going to. I believe this should be controlling an outdoor flood light which is directly above this location about 30 feet.
4. 14/2 cable incoming hot.

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As an experiment, I hooked up the black from cables 3 and 4 to a single pole switch, tied together the neutrals, and switched on hoping the outdoor flood would work. It did not.

My ultimate goal would be to get the flood light working, so that's my main mission. But if possible I'd also like to remove cable 2 from the box and have the garage overhead controlled by the other switch. Any ideas from the experts? Thanks.
 
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Old 05-04-15, 09:52 AM
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I'm guessing you had the cable wiring spread out in groups.

The neutral from cable 1 and cable 4 is connected together.
A switch from the black of cable 1 and the black of cable 4 will turn that light on.

Garage overhead light:
With cable 2 ONLY .... it looks like the end of a three way circuit. I don't see the need for removing the wires from the box. You can eliminate a switch there by connecting the red to white and cap off black OR red to black and cap off white. The difference to which two wires you combine determines the other switch operation... up for on and down for off.

Can't help you with cable 3. We can't tell where it goes from here. You think it feeds the floodlights. If that were true you should find that three wire cable there. If not... you will have to physically trace the cable to its end.

As an experiment, I hooked up the black from cables 3 and 4 to a single pole switch, tied together the neutrals, and switched on hoping the outdoor flood would work. It did not.
Try the red on the switch and white as neutral.

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Old 05-04-15, 11:36 AM
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Thanks pjmax. Awesome advice. That 3rd cable is a head scratcher. The flood light is too high up for a ladder and I had to lean over my roof to install it, so I wanted to do a "one and done" and get it over with. So I made sure there was no power, installed the fixture and sealed it up with silicone thinking I would figure out the switches after. DOH! Anyway, that box definitely only had a black, white, and ground, which I connected to the corresponding wires on the fixture. Perhaps the red was capped off and hidden behind the box, but I did not notice it.

Here are the reasons I think this is not working:

1. The 3rd cable has a switch somewhere else which I haven't been able to find.
2. The 3d cable goes somewhere else entirely and has nothing to do with the flood light.
3. The flood light itself is defective (unlikely since I just bought it).

Any other reasons you can think of? If you were going to troubleshoot why the flood light is not working, what else might you try? Thanks very much!
 
 

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