2 gang switch problems

I have replaced a 2 gang switch that operates the the hall and first floor landing lights.

I copied exactly the wiring from the old switch to the new switch but when testing both upstairs and downstairs lights work together from one side of the switch. Nothing works from the other side of the switch. This applies to both upstairs and downstairs switches.

The wiring from the old switch was as follows

1st gang: earth to common / red & brown to L2 / blue & blue to L1

2nd gang: brown to L2 / blue to L1 / earth to common

When I reconnected the old switch all was fine

What am I doing wrong

you should not have brown that is flex, i would suggest you call an electrican to check it out, you do not know what else may be wrong / dangerous

I take it each switch is supposed to operate one light each.
The fact you have terminals 'com' L1 and L2 means you have two way switches that you want to use in a one way mode, this means you will only use the 'com' and 'L1' terminals. L2 will not be used.
Electric will go in the switch at 'com' and come out at 'L1'.
What have you done wrong?
Well there is no path from L1 across to L2.so nothing can work and theres the first error.

The bare 'earth wires' should not be connected to any of the above terminals, they are for connecting to the earth terminals on the metal box which should also have a link to the earth terminal on the switch.
So theres another error
Remove the bare earth wires from 'com' and put the wires you have in L2 into 'com'.
Connect the earths up as described above.

you still should not have mains flex (blue and brown) in a switch which is on the wall

Scotty said:

I have replaced a 2 gang switch that operates the the hall and first floor landing lights.

I copied exactly the wiring from the old switch to the new switch but when testing both upstairs and downstairs lights work together from one side of the switch. Nothing works from the other side of the switch. This applies to both upstairs and downstairs switches.

The wiring from the old switch was as follows

1st gang: earth to common / red & brown to L2 / blue & blue to L1

2nd gang: brown to L2 / blue to L1 / earth to common

When I reconnected the old switch all was fine

What am I doing wrong

Click to expand...

That entire circuit (the two way lighting) requires rewiring. NEVER should the Earth core of a cable be used as a live core. The circuit has no Earth connection.

IT IS DANGEROUS, and as the others have advised you, Call an Electricians to sort out the mess before someone gets hurt.

Thanks for the advice guys, I will be calling an electrician out straight away.

Just one further query. Do you think the current wiring for this circuit would be standard for the house ( a 1930,s build) or does this appear to be someone elses bodge.

bodge, because blue / brown flex is only used in flex, not cables, also (not sure EXACTLY how long) brown / blue flex is only about 15 years old, so it could NEVER have been done when house built