Figured it out for anyone looking to do the same.
For the downstairs switch you simply give it a 12v live from the downstairs circuit, then completely remove all 3 wires linking it to upstairs.
For the upstairs switch you also remove the 3 core wires so neither switch is physically connected to...
So I've managed to replace the 2 gang 1 way porch/outside light switch without issue. Finally I'm attempting to tackle the last pair of switches I want to swap out. Landing light.
Downstairs 2 gang:
Left side: Upstairs landing light
Right side: Downstairs hallway light
Right side seems pretty...
Anyway all buttoned back together after fitting the capacitor and working flawlessly via Smart Life and by voice command to Google Home.
Decent build quality, just hope they last so I don't have to go in there again. Master needed a 10mm spacer, other switch everything fit in the 35mm backbox...
I posted that post just after you posted yours so I didn't see it.
And yes it is. The guide shows just a neutral and live going to L on the second switch, despite buying a 'no neutral' switch so I thought just having a permanent live to L would allow the switches to communicate to eachother via wifi
I've almost sorted it. To confirm
Master switch:
L = Perm live from consumer unit plus brown wire from 3 core linking switch 1 to switch 2 to provide a perm live to switch 2
L1 = Live from ceiling light, plus brown sheathed black strapper wire to provide 12v to L1 at switch 2 else it won't...
2 in each
L: Black with brown sheath to send power to the L terminal on switch 2, plus solid brown to send permanent power to switch 1.
L1: Brown with brown sheath - live coming from light. And a solid brown, again to send power to the L1 port on switch 2 as it won't power up without 12v to L...
OK I have it working as it should. Switch 2 does need power to L1 else it won't power on. So the diagram supplied is wrong.
However now the kitchen lights dont work
Switch 1: Both solid browns to L (1 way and comm from old switch)
Black with brown sheath and brown with brown sheath to L1...
I've sent a confirmed 12v feed to the L terminal on switch 2 and it doesn't power up.
I swapped the switches over and it will power up then. So the wiring diagram provided must be wrong. Something has to go into the L1 terminal on the second switch to make it power on
I did as you said and it didn't power on. However I switched the sheathed brown cable (which on the old switch was in the 2 way terminal) with the other 'i way' brown, the switch now works. So the sheathed brown wire must be the wire coming from the light.
To confirm at the master switch:
L =...
I must have fried one of the switches because I put a confirmed 12v live to switch 2 and it doesnt illuminate anymore when connected to L. You have to put 2 wires in the L feed to switch one to provide a permanent live to switch 2, as switch 2 doesnt normally have its own permanent live. Got...