Lights Dimming

Here we go...

Replaced standard pendant in downstairs cloak with B & Q downlighters using new ceiling rose. Also replaced pull cord as this had jammed. Lights work fine. However, there is a spur from the cloak to the garage and outside light. These lights come on but then dim. Also, if I turn cloak lights off and outside light on, the cloak lights come on very dim??

Where has it all gone wrong?

Ta

It's probably all gone wrong with the way you've wired it up. Have a look at the diagrams in the Reference thread at the top of the forum, and see if they help.