Hi, I have just changed the light in my bedroom that had an intermitant fault. When I put the power back on the light didn't work neither did the lights in the bathroom or 2nd bedroom. i have checked the wiring to the light and its correct. Has anyone got any ideas?

Planty111, December 2009

Thanks again Adam, the wire ran to the bathroom. I put the meter on it and found the open neutral and noticed the wire was broken about an inch from the end. I have fixed it and now all the lights are working fine.

I still don't understand why changing the main bedroom light fitting should show this fault up.

But once again many thanks

planty111, December 2009

The neutral which you got a reading from will go back to the consumer unit, the one which didn't give a reading will go to either the bathroom or second bedroom, which there could be a problem with.

Adam, December 2009

I've just checked for voltage and its fine so I guess its the open circuit neutral. If so I need to get in the loft and find out where it goes.

planty111, December 2009

Again thanks for your input. I haven't got a neon screwdriver yet. I did notice however when I was checking the live switch neutral was right with a meter that across live to neutral on the two other neutral wires one had a reading and on the other there was no reading at all.

What would this indicate?

planty111, December 2009

When I say "the next fitting" I mean the last one that is working.

Adam, December 2009

That does sound right. There is obviously a live and neutral supply at the rose you have changed otherwise the fitting wouldn't work.

Go to the next rose on the circuit and test for a live voltage with a neon tester screwdriver or non-contact voltage detector. If it lights up you can be sure the problem is with the neutral, if it doesn't the problem will be with the live.
The problem will either be with the connection in the next light fitting, the cable feeding it, or the connection in the fitting you have just changed (most likely because this is the last thing you changed and everything was working before).

Adam, December 2009

Thanks for your input, I have three live wires that are connected together and then to nothing else, two neutrals that i wired to neutral on the light fitting and one neutral with a red tag on it that I wired to live on the light fitting which I believe comes from the switch. 3 earths wired to the light fitting.

No breakers have blown

Does that sound right or not?

planty111, December 2009

I would suggest the wiring is not correct because the lights don't work.

There should be a live and neutral feed coming from the light you have replaced and going to the other lights on the circuit. It sounds to me like you have put this in the wrong place.

Adam, December 2009