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I have two switches in my living room. The one inside the door entrance switches the light on and off. On the other side of the room by the back door is a 2 gang switch which switches the living room on and off but also switches the outside light on. The rear of the current switch has L1 at the top with a brown wire and L3 at the bottom with 2 brown wires and nothing in L2. The other end has L2 at the top with a black wire and L3 at the top with a grey wire. At the bottom is L3 with two brown wires and L1 with a black wire.
I have bought a new switch and at the top it has L11 and L1 at the top and L12 at the bottom. The other side has L21 at the top and L2 and L22 at the bottom. Because the two connectors are different to the current switch by having the two connectors at the top instead of the bottom has completely baffled me. Could someone help me to work out which wires go where.

billy2608 wrote: Because the two connectors are different to the current switch by having the two connectors at the top instead of the bottom

Turn the switch upside down

I have tried turning it upside down but the light switch at the entrance wont switch on or off. I am confused with the L11, L12, L21 and L22. If the brown wires are in L1 and L3 on the old connector where do they go in the new connector. The single connector at the top of the old connector is L1 but the single connector on the new switch is L12. The two connectors on old switch has two brown wires going into L3 but the new connector has L11 and L1 so which one replaces L3.

Pictures of the back of old switch and new switch.

I have managed to attach the photos.

The terminal configuration looks the same on both switches (Out of focus picture does not help) I have never seen a switch such as you have, make and model / where you purchased it from may help.

This is the link from Amazon where I bought them.

https://www.amazon.co.uk/dp/B09K6YHRXH? ... tails&th=1

Thank you

I have been searching for a "diagram" of your switch, all those that I have found have wires in the way. BUT yours doesn't but as it's a poor quality picture I can't confirm what I have found. Can you please take an in focus picture of the back of your switch.

Good Morning and thank you so much. I have tried so hard to take photos of the back of the switch but I just cant get it focused. I have a photo and named each terminal.

Not perfect, but it does help immensely. (You will have to work on your photography skills, no, not joking, you may need it someday)

Note: Read the whole of the following TWICE before you do anything else.


As you have 4 browns, 3 are light brown, 1 is dark brown, tape the two light browns that are now in L3 together, while they are still in the switch. (That way, they will always stay together, this is very important)

You are looking at the back of each switch.

Below is for each half of each switch.

Old switch ..........New switch (Left half first)
L1 = ------------------- L1 (Light brown)
L2 = ------------------- L12
L3 = ------------------- L11 (Light brown x 2, you taped them together)


Old switch ..........New switch (Now the right half)
L1 = ____________ L2 (Black)
L2 = ____________ L22 (Dark brown)
L3 = ____________ L21 (Grey)

Don't rush.

FYI.
Both old and new switches are 2 identical switches side by side, BUT the left part is upside down in relation to the right part. Have a look at the old white switch, don't look left to right, look top to bottom.

Thank you so much. As its dark I will try tommorow. I have read it over and over so I wont be making any mistakes. I will let you know tommorow. Thanks again.

Just don't rush, and tape the two browns together while they are in situ first.

Good Morning. Thank you and I really appreciate all your help. I couldn't have done it without your help

I wired up everything as instructed and unfortunately nothing worked. I could not get any lights to work. I have studied your instructions and studied the old wiring in the white switch and completed the following:-

Old Switch = ......................New Switch
L1 =....................................L11 (light brown)
L2 = ...................................L12
L3 =....................................L11 (light brown X2 taped

L1 =...................................L21 (black)
L2 =...................................L22 (dark brown)
L3 =...................................L2 (grey)

After all the above wiring all lights are working however the switch near the back door that feeds the lights in the living room when you switch it on it flickers the lights but wont turn them off and on. The light switch just inside the door is working fine. The outside light is working fine. You just cant switch the living room light on and off with the switch near the back door. It seems like one of the wires may be in the wrong place but not sure which one as its only the light brown wire and double light brown wire X2.

You have no means of testing, I am not there, I have tried to help you based on the information given, you will need to call an electrician to physically check for the error. Or you could put the old switch back. (And in future, don't buy switches with odd terminal locations from Amazon.) smiley face

Thank you so much. You have really helped me so much as I would be lost without your help. I will contact an electrician to assist. Thank you again.