I have 4 red wires to fit into a double switch which L1 L2 L1 L2 and 2 terminals at the other end linked together, my problem is i cant get the lights to work indivually or together, and for some reason one of the lights in another room doesnt come on - help appreciated.
help switch wiring
- Thread starter PARKLANDS
- Start date
Step 1: Leave the switch out of it for now. Join two of the red wires together with choc block and isolate the other two. Does the other light work now? There are six ways to pick two wires out of four. Try them all until you find two that work. Some will cause your new lights to come on. 
This is normal. 
Step 2: Put those two wires into the COM terminals of the two switches. That's the ones that are linked together already. Leave the link in. Does the other light still work?
Step 3: Put the remaining two wires into the two L1's. Do your new lights also work?
Step 4: If the switches control the wrong lights, eg the right hand switch controls the left hand light, swap the two wires in the L1 terminals. If a switch works upside down, move the wire in that switch from L1 to L2 IN THE SAME SWITCH! Happy now?
This is normal. Step 2: Put those two wires into the COM terminals of the two switches. That's the ones that are linked together already. Leave the link in. Does the other light still work?
Step 3: Put the remaining two wires into the two L1's. Do your new lights also work?
Step 4: If the switches control the wrong lights, eg the right hand switch controls the left hand light, swap the two wires in the L1 terminals. If a switch works upside down, move the wire in that switch from L1 to L2 IN THE SAME SWITCH! Happy now?
space cat! I don't quite follow your reasoning, well I do if both these switches are for one way systems, but why have a link across the two coms.
My thought was that one red to provide a live to one com, which would leave three reds. My thought was that one red was for one switch in one way system and the other two were the strapper wires for the switch in a two way system.
If there were two live reds why have a link across the 'coms'
Unfortunately OP didn't say if one of these switches was in two way system.
I suppose it boils down to how many of the four reds are live, 1 or 2.
Or am I missing something here.
My thought was that one red to provide a live to one com, which would leave three reds. My thought was that one red was for one switch in one way system and the other two were the strapper wires for the switch in a two way system.
If there were two live reds why have a link across the 'coms'
Unfortunately OP didn't say if one of these switches was in two way system.
I suppose it boils down to how many of the four reds are live, 1 or 2.
Or am I missing something here.
PARKLANDS said:
I took this to mean that a light which once worked somewhere else, but which has nothing to do with these switches, no longer works. It follows from this assumption, which might be wrong, that two of those four reds should be permanently joined.
PARKLANDS, if I have misunderstood your post please let me know.
Are any of the lights that this switch controls part of a 2-way system? IE. Can you switch any of the lights from another location besides this switch?
Parklands! You asked for help. Now we're in the dark!
Any chance of a response. Is problem now fixed, if so how?
Any chance of a response. Is problem now fixed, if so how?
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