Changed 2 gang 1 way switch in lounge, now no kitchen light

My living room dimmer lights did not work properly so I decided to open the switch box to check the wires. It is a 2 gang 1 way switch. When I opened it, there were four red wires and one yeallow/green (I guess it is earth?)

For some stupid reasons I mixed up all the wires and I tried to reconnect it. Sofar I've managed to identify 2 red wires to the lights, and one red live wire from supply. The other red one I have no idea what that is since it does not have any power (I tried to connect it to the light wire and it did not work). This one was the one that connected to C on one side, and lenghthened to C on the other side. Since I didnt know what it was and it didn't have any power, I taped it up, connect one light wire to L1, one supply live wire to C. When I turned on our main switch, the light in the living room is fine (only one of them working since I could find only one live suppl wire). However I now realised there are no lights whatsoever in the kitchen. Outlets are still fine.

Anyone has any idea where I've gone wrong?

Am I correct in saying there should be 2 live wires from supply and 2 wire to bulbs? Did I somehow managed to break one live wire, hence break the rest of the light circuit?

I'll call an electrician next week but in the meantime any pointer is much appreciated.

There is no 100% sure way to tell without seeing it and testing it in the flesh, but the most likely problem is that the "spare" red wire you have with "no power on it" is in fact the wire that carries the supply on to your kitchen light and should therefore be connected to your permanently live red supply wire. Both common "C" terminals of the switches should be linked together with a short piece of red wire too, then you will have a supply to both switches.

Thanks Robin. You're so right. I've just untaped that wire and connected it to the live wire and kitchen light is now on again! Now just have to buy a new dimmer switch so that both lights in my living room can work! Six frustrating hours on saturday, now finally understand the lighting system in my house!

So you got the lounge light working, what does the other switch do?

andantespianato said:

Six frustrating hours on saturday, now finally understand the lighting system in my house!

Click to expand...

Don't be so sure..

There's at least 20 ways to hook up lighting circuits.

Always identify each wire and take notes or pictures before undoing anything.
But you know that now.....glad its all working.

It is a 2 gang switch for both of my lights in the living room. Somehow one panel is broken, hence my problem in the first place! But at least I know now switch is the problem and should be replaced

@ Taylortwocities: I should rephrase that to 'one step closer to understanding how my lighting system works'


Another question is I've changed one of the light shade together with the bulb hanger, but the one I bought from B&Q has a smaller base than my previous one. Now I have an unsightly hole on the ceiling. Is there an easy way I can cover it?