I am rewiring a 3 gang 2way switch.. I found 4 black wires and 2 red, how do i rewire that ???

Question

when i removed the old switch, which was working correctly. i copied the wiring to the new switch, however now two switches work 2ways but the 3rd switch does not work at all

can you help

Answer 1

Do you mean 'replacing' a 3 gang switch, as you said 'rewiring'?? If each of the three switches are operated as 2 way you need a minimum of 7 cores, one loop feed and 6 pass wires. If it's not the feed end you will need 9 cores, so I can only assume that one of your circuits is one way only?? If you had loops to each common terminal put them back in place first and post some more information. The black cores that you have, should have been marked with red tape or sleeving when installed.

Answer 2

This is very difficult without more information, however you could try taking a link from the nearest common to the common on the switch that isn't working. If you already have a wire here,take that wire to the other unused terminal.

Failing that, you would really have to give us more info.

Would I be right in assuming that you have a one two-way switch and two one-way switches? Or is it the other way round?

What are the switches used for?

What does the other two-way switch look like - ie the one that operates the same light?
Using a multimeter, you could check that you have the correct wires in both switches.

If that doesn't do any good there are further checks you can make, but I'm not too anxious to advise because I don't know your level of competence, and it involves checking with the power on.

Get back to us and give as much information as you can. Best of luck.

Answer 3

The only thing I can think of is that you have a wire hooked incorrectly. There should be a common screw on each 2way switch. Make sure you have it hooked properly according to your initial wiring diagram (the one you drew). If it still does not work, you are going to need a voltage tester and flip switches to find your "traveler" legs and you hot/switched leg. Good luck.

Answer 4

Check for voltage at the non-working switch. May be a loose pigtail. If it is a 3-way switch also, make sure that the two wires in the same cable are connected to the traveler screws, the other should be your common.

Answer 5

For your peace of mind by the sounds of it you need to get a 'Periodic Test' carried out. The youngest your wiring could be is about 5 years when the colours changed but is could be over 50.Obviousl this will depend on the age also of the property.

Answer 6

This is difficult to explain, I have the Collins complete Do It Yourself manual in front of me but if you have 4 black wires and 2 red, you are not working with the same colours.
What I would have done in your case is mark where each wire was as I disconnected them.
From the circuit cable 3 wires come down into the 1st switch, the earth joins a earth connection away from the switches, I don't have earth on mine. Of the other two wires the red goes to L1, the black goes to L2, on the common connection another red wire is connected that goes straight down to the third switch, it is probably joined at the middle switch, but isn't connected to the middle switch, it connects to the common switch on the other end switch. so we have a red wire connecting the first common to the last common.
Back to the first switch, with the red wire at L1 there is another wire (in the book it is yellow) this wire goes to the right hand top L1 in the middle switch.
With the black wire on switch 1 L2 is another wire (it should be blue) that goes to the left hand top L1 in the middle switch.

The middle switch, This has (apart from Earth if you have it) 4 wires connected to the switch none of these are red, the red wire joins onto more red which goes down to the 3rd switch.
If this is the switch you are re- fitting, you have 2 wires from 1st switch connected to L1, 2 wires are fitted to L2, in the book the blue is in line with the blue in L1, and the yellow is in line with the yellow in L1.

3rd switch, The right hand L2 wire from the middle switch connects to the L1 on final switch. The Left hand L2 swich from middle switch goes to L2 on final switch. The red wire goes in common switch on final switch.
Sorry about the long details, as well as the colours you need to observe from what direction the wires come. The easiest mistake could be the L2 in middle switch, by swapping them, it could make the third switch work.
I tried copying the page to send you a picture, but couldn't get a good picture from the book.
I tried looking on internet for a diagram, found one good one but it is different from my book, this follows.
http://www.ultimatehandyman.co.uk/three_way_lighting.htm

I think that was my longest answer ever lol.

Answer 7

I think you have used a common on the wrong side of the switch. You need a voltage tester to find out which one. E mail me if you have any questions.

Answer 8

he said two way not three way