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3 wires...2-way switch...1 light! how to rewire?

A light switch in my bedroom came loose when I was painting around it and I can't figure out how to wire it back correctly.

There are 3 brown wires coming out of the wall and I have a 2-way switch (L1-L2-COM) which operates one central pendant light fitting.

However, when I wire the 3 wires back up to the L1, L2 and COM (I've tried all possible combinations) the bedroom light works fine...BUT it also turns off the light in the neighbouring bedroom.

I want to use the switch as a 1-way control only as it used to be before I knocked it loose, which I understand means ignoring the L2 terminal? But then why do I have a third wire? And what do I do with it?

Any advice much appreciated!

4 Answers from MyBuilder Electricians

Best Answer

Work out which wire is the live feed and connect this to common.
Connect the other wires one at a time to L1 and by switching on ascertain which one turns on the bedroom light, connect this to L1.
Connect the remaining wire to Commom with the live feed.
This should sort out the problem.
Always follow safe isolation procedures, only work if you are competent.


Answered 9th Jun 2015

Red to Red,Black to Black,blue it to bits.


Answered 9th Jun 2015

The only truly effective method that doesn't involve trial and error is with a continuity tester (low resistance ohm meter)... Generally I'd say it's difficult to advise without testing it but I suspect you need to terminate two of the wires together in Com and the other in L1 leaving L2 out completely.


Answered 8th Jun 2015

You'll need a multimeter or similar to test which is the live incoming feed, which is the switchline and which is the feed to the other bedroom. Two of the three will go together in the common and the switchline goes into L1 on its own, thus leaving L2 empty. 10 min job for an electrician.


Answered 8th Jun 2015

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