Geezers help me out here. I took down an outside PIR light to replace it and did not look at the wiring. There is a 4 gang light switch in my kitchen. I know which switch operates the outside light. When I opened the switch there is a red cable going in and one going out. Electrical tester confirms power to outgoing wire when switch activated. Outside there is a red wire, a black wire and a earth wire (green & yellow) coming out of the wall. Within the light I assumed red went into brown, black into blue and earth to earth. But no light (even changed over lamp bulb to another and turned dusk to dawn switches etc). Electrical tester seems to suggest both red and black leads are live. So how do I wire it? :shock:
I can't see anything wrong with what you have done or what you consider to be correct way to wire.
But I think you have lost a neutral! This is unlikely to be the switch and is likely where it takes it feed from a ceiling rose or a fused spur unit etc.