Hope the subject was clear. If not...

I have 2 3-way switches on my hallway. If both are in the same position (either off or on) the lights are on. If they are opposite the lights are off. Other than turn one switch upside down, what could be the wiring issue?

Thanks in advance!

  • 4
    That sounds like normal operation to me, are you wanting opposite behavior? I don't see the problem.
    – Tyson
    Apr 15, 2017 at 22:39
  • 2
    3-way switches don't have on/off positions, flipping the switch at either end should cause the state of the light to change, because of that up for on, down for off doesn't apply.
    – Tyson
    Apr 15, 2017 at 22:40
  • 1
    Are you sure you have the description of the problem stated correctly? 3-way switches normally do not have an OFF and an ON position. Instead they can be UP or DOWN if mounted in the common vertical position. There are multiple incorrect ways to wire up 3-way switches but usually these lead to the light being ON with one setting of the switches and light OFF with any other combination of the switch positions. Double check your fault statement and correct if needed. That said it sounds like your switches are working normally.
    – Michael Karas
    Apr 15, 2017 at 22:41
  • Thanks all. Basically they are working as an xnor gate instead of an xor gate. If there's no issue with the switch flipped so "top" is down then that fixes my OCD. In all testing both switches will work the lights regales of the setting of the other one. In other words if one is up or down the other will turn lights on and off.
    – Ben
    Apr 15, 2017 at 23:35
  • 1
    Swap the travelers at one of the switches - doesn't matter which one. OCD fixed (for now at least ...).
    – brhans
    Apr 16, 2017 at 4:07

1 Answer 1


This is how 3-ways work

You have described what is utterly normal for 3-ways. If you don't like opposite=off, do as brhans says in his answer that he's about to write. And I'm with you, I do that all the time.

Or go another way with a relay

You can't just use random relays out of the Mouser catalog. However they make mains-wiring-listed relay modules legal for this, and they fit in a junction box knockout or inside a box.

Use a latching relay. This has two coils and a common. Energize one coil, the relay throws on and stays. Energize the other, the relay throws off and stays. Energizing need be only momentary.

You use these with a special momentary SPDT (in other words, a 3-way) switch that lives in the middle position until you push it up or down. Now you can use the 3-way switch wiring to carry common and two coils.

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