bathroom lighting

Hi One of our bathroom lights stopped working a while back despite replacing the bulb. Finally, go round to taking a proper look. Bought a replacement lamp holder with wiring but the light still doesn't work. It is showing a voltage through all the wires but tried several different bulbs and it...

Any ideas/help. We are renovating the bathroom where all wiring is in the loft and over boarded so cannot get at. The lighting circuit is wired via a junction box somewhere under the floor. So only exposed wire is the live/neutral for the pull switch and at the other end, live/neutral of the...