DIY Doctor UK DIY Forums

Hi I hope somebody can help me out there, I have just bought a new Dual dimmer switch (One switch for the main lights, one for the wall lights) I already had one installed however one of the switches was broken hence the new switch. I know I should have taken more care when taking off the old switch but unfortunately I didn't and now don't know where to put the wires in the new switch. I have two Red wires One Black wire and an earth. I also had a strip of wire that bridged between the two terminals. I have attempted to put it back together but unfortunately the wall lights would only work while the main switch was on. The light switch has 3 slots for each dimmer L1, L2 & C. Please could somebody out there help me out and let me know which wire to put into which slot.
Thank you in advance

You need to find the common wire. The link will go between the two C's (Common) but before you fit link you need to find common. Put one wire in C and other in L1 and remaining in other switch so it can't touch any thing. Try switch both ways if it works swap one wire with other switch until it does not work. We now know wire in other switch is common so that will be linked into both C's and two wires in the switch we used to test will go to two L1's one in each switch. Always turn off power between each test. Earth to earth of course. If you don't understand then don't do it get someone in be safe.

The idea is when you connect the two wires to the two lights together nothing will happen but if either connected to feed light will come on without a meter it is only way I can think of to find which is which.