I have a ceiling light that is controlled by two switches, however when one of the switches is off the other switch does not work. What is the issue and how can I fix it?

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    a very similar question has been answered before. Please check out this link and see if it answers your question. Welcome to Stack Overflow! diy.stackexchange.com/a/8277/19358 – Rob Elliott Jul 24 '19 at 14:20
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    Have these 2 switches ever worked together? – brhans Jul 24 '19 at 14:54
  • We'd need to know how the switches are wired to answer this question. – isherwood Jul 24 '19 at 15:28
  • Post a picture if possible. We don't even know if 3-way switches are installed. – Valkor Jul 24 '19 at 19:25

Well, look at the simple diagram below:

enter image description here

If one switch is stuck then the other will complete the on/off function, but if one of the parallel wires is broken then the symptoms will be similar. A multimeter to test what is happening would be my next move.

As my simple diagram seems to confuse people, here is a picture taken from this source which shows a similar circuit, but this only needs a single wire to go between the two switches...:


(source: Light Wiring Diagrams)

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    Mike look at the 2 comments that link to how to properly wire a 3 way switch, this is a very common problem and not a single throw switch issue as this issue will always be the case with single throw (on off) but a double throw (3 way) has this issue when improperly connected. – Ed Beal Jul 24 '19 at 15:23
  • @EdBeal are you saying the OP has switches that are 3way ie on-off-on or 2way ie on-off... – Solar Mike Jul 24 '19 at 15:34
  • The only way 2 switches can properly work on 1 circuit is 3 ways not on off on but common normally open and normally closed. The 3 way switch only has 2 positions it toggles from NO to NC , a single throw switch is only open or closed so this would never work with a simple on off switch. – Ed Beal Jul 24 '19 at 15:55

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