I have a hallway light in a 4 way circuit configuration. The problem I have is that when the 4 way is in one position all three switches work correctly. In the other position one of the 3 way switches works, the other does nothing.

I have followed the troubleshooting guides by disconnecting the wires identifying the always hot, connecting it to the black common terminal on the first 3 way, tracing the hot and it's matching pair and connecting it to the 4 way switch. The switch does not have "In" or "out: identified. I have tried connecting to both sets of screws. (I am correct that the pair of screws to be uses are directly opposed (right and left of the switch, not both on the same side).

I then attached the travelers to the other set f screws on the 4 way switch and identified them and connected them to the brass screws on the second 3 way switch. I then connected the final wire from the lights to the second black screw. Per the instructions everything should work, but the same 3 way does not work. The other 3 way works regardless of the position of the 4 way.

Do I have a bad 3 way? perhaps a bad 4 way? HELP!!

  • 1
    Some 4-way switches have the travelers from one 3-way switch connected to one side and then from the other side to the other 3-way.
    – JACK
    Mar 24 at 22:24
  • Is this a "new" problem?
    – JACK
    Mar 24 at 22:25
  • How long has this problem going on? Do you have some way of testing the individual traveler wires for voltage? Mar 24 at 23:03
  • My daughter just moved in to the home as a rental. The switches worked that way from the start. It is currently wired with on set of travelers on the top of the 4 way and on on the bottom. I could not identify an "in" side of the switch.
    – Joe
    Mar 25 at 0:31
  • ThreePhaseEel...yes, I can check for the presence of voltage. I don't have a meter, just a voltage detector. when I rewired the circuit I followed the power from one switch to the next using it, in my final connections I could see the power switch from one traveler to the other when I changed the position of the 4-way. I thought the entire circuit was wired correctly at that point. That is why I am suspecting a problem in one of the switches, The 3-way that is not working correctly is the one where the hot wire enters the circuit.
    – Joe
    Mar 25 at 0:38

To me it is a single mis wired 3 way switch, @jack was almost correct (all) 4 way switches swap the 2 travelers from 1 side to the other+. Replacing a switch is allowed if the landlord approves in all the locations I have worked as a licensed electrician. Some jurisdictions like NY a home owner can’t do basic maintenance so it is best to know.

I would check to see where the hot is coming in on the switch note the connections photograph them or record the connections if you don’t have a meter. It sounds like a traveler and common at one of the 3 ways is reversed.

The good thing is if you have access to the breaker panel (you should by code) this is easy to figure out trial and error with in 4 tries.

Pick 1 switch power off swaps trailer and common turn power in and test did not fix power off now the other trailer is moved to common swap and test no better return to original and go to the other 3 way and repeat the same sequence.

There are 2 travelers at each end one of these is mixed up with a common. If incorrectly connected it doesn't work properly in 1 or 2 of the combinations there is no damage possibility using the same wires on the 3 terminals (don’t touch the ground) all the 4 way dose is flip the traveler pairs.

It can be faster for an electrician to do this test than take measurements and make the change I have done this many times with the exact same issues and had success.

  • Thanks for your insight Ed!
    – Joe
    Mar 25 at 18:09
  • Ed, I tried switching the travelers in every combination with the common on both 3 way switches. That did no fix it and anytime I moved the hot wire from the breaker (lets say on 3-way #1 to a brass screw I was unable to shut the light off with any switch. I even tried moving the traveler pair from the top to the bottom on the 4-way and also tried putting a mixed pair of travelers on right and left, no improvement. I replaced all of the wires too the locations I chased the power and believe it is wired correctly with one set of travelers on the top of the 4-way and the other set on the bottom.
    – Joe
    Mar 26 at 0:52
  • In the current configuration the hot wire from the breaker is connected to the black common screw on 3-way #1. Travelers on the brass screws. On the 4 way one traveler pair on top and the other on bottom. 3-way #2 has the single load wire on the common and the traveler pair on the brass.
    – Joe
    Mar 26 at 0:54
  • With 3-way #1 in the on position neither the 4-way or 3-way#2 work, only 3-way #1
    – Joe
    Mar 26 at 0:55
  • With the 4 way in position 1 all three switches will control the load.
    – Joe
    Mar 26 at 0:56

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