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Lights go on or off at will

I have an odd problem. A light is on 3-way switches at each end of the hallway. Sometimes you can switch the switches and the light will not come on. I changed both switches, and it made no difference. They are wired correctly. Sometimes the light will switch on. When it is on, either switch will turn it off. When it is off, sometimes it will go on by itself. Obviously one switch is in the on position at the time. Sometimes we'll go to bed and the light is off, then wake up in the middle of the night and it is on.

I could understand this a bit if something happened to jiggle wires or something, and a loose connection was being jarred on or off. But no. Nothing seems to happen to change their on/off state.

It's a bit of a mystery.

Re: Lights go on or off at will

Alan, If you used the back stab connections in the back of the switch they probably are not striped enough or need to be pushed in further. Or the wire is not tight on the switch terminal. Make sure you wrap the wires clock wise as it makes a better connection.
I also think the three way switches are still wired wrong.Try starting over as I describe below it is cheaper and faster way of fixing your problem.

here is what you do. A easy way for a layman to troubleshoot them if you do not know the theory how they operate is to remove both switches.Supply two new 3 way switches. clear all the wires. Take your tester and put one side to a ground the other side is used to touch each wire(3 wires in each box). Find the only wire that has full voltage. Take the wire with voltage and connected to the common terminal on the switch. Then take the other wires in that same box and connect one wire to each of the two terminals on the switch. then go to the other switch and find the energized wire in that box and terminate that to any terminate other than the common terminal. Go back to the other switch and turn the switch the other way. Go back and find the other hot wire and terminate that wire on the other terminal on the switch not marked common. The last wire should be terminated to the common terminal on the switch. your done. Good luck

Re: Lights go on or off at will

It has been my experience that when strange things happen like this people always check the power connections but ignore the common (usually white) connections. A loose common can have the same effect and is not dependent on the orientation of the switches.

Re: Lights go on or off at will

Good call Jack.. I should have mentioned to check the wires that have wire nuts on them. Make sure they are tight.

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