Using your diagram/ photo, it’s time to re-wire the new switch, stripping the wire if needed to ensure better contact in the port or if the copper wires is damaged or crimped. Using your small flat head screwdriver, loosen the screws clamping down the wires, releasing them from the switch fitting. Release the wires from the switch fitting It can get very confusing when there’s more than one switch and lots of brown wires floating around! 6. Using masking tape and a pen, label which wires went into which port before you disconnect them. Your new light fitting should come with an instruction leaflet to help you identify which wires go where. For mine, the wire was a little too short, so I had to trim some spare wire I had to ensure it reached between the COM ports. (To make things even more confusing, the switched live wires can sometimes be completely brown.) You may also have a separate wire connecting the two switches via the COM port on a multi switch fitting to connect the circuit. You will notice that the brown wires from the wall goes into the COM port on the existing switch and the blue with a brown sleeve switched live wire will be going into the numbered L ports. If your setup differs from a standard 2-wire system, it could be a 3-wire lighting system which usually includes an additional neutral wire that goes into the light via a connector block as per the poorly drawn diagram below.

The neutral wire takes power to the light and the switch sits on the live wire to complete/break the circuit.

The live wire brings the power supply to the switch. If you live in an older property, the wires may be black and red, red being Live and black being the Neutral. This is a ‘switched live’ wire connecting the light to the switch.

There will also be another brown wire, or a blue wire with a brown sleeve coming out of the switch into the wall. This is connecting the switch to the fuse box. You will have a 2-core cable (or multiple) from the wall with a yellow and green (earth) wire earthed inside the wall box, a brown (live) wire going into the switch and a blue (neutral) wire. Take a photo or draw out the layout of the current wire setup.

Double dimmer switch