I have 2 downlighters from 1 switch in 1 room. 1 works the other does not. The bulb is fine (I've switched it between the 2) and, if I pull the bulb slightly away from the fitting to expose the terminals, there is power registering with a circuit tester in both terminals.
So how come the bulb does not light?? Am I going barmy?

RoyK, November 2011

Thanks toptrish but I've already changed the ceramic base unit but still no joy.

RoyK, December 2011

it will be the ceramic base that the prongs fit into,the contacts burn up

toptrish, December 2011

It is a low voltage system the lamps with the 2 little prongs

RoyK, December 2011

circuit tester is no good it just tells you there is voltage present,it not tell you if you have a neutral return,you need a test meter,you dont say if its low voltage,or gu 10 bulbs,you must give more information,gu 10s are 240vts low voltage are fed by a transformer,

mm, November 2011