Lights not working

[Wiirone]

Hi all,

The ceiling lights in two upstairs bedrooms have suddenly stopped working. The 3rd bedroom, bathroom and landing lights are working fine.
I have checked the bulbs. I have checked that the wires in the wall switches and the light fittings are connected. I have used a tester screwdriver (with neon light - yes, knowledge of electrics limited!) on all these connections and there appears to be power at both switch and fitting. One wire becomes 'dead' when the wall switch is turned off as expected. No electrical work has been done in the house to have disturbed anything and the circuit for the upstairs lights at the consumer board is of the 'trip switch' type.
Above one of the affected bedrooms is a 4th bedroom (loft conversion) which has a bit of a springy floor due to poorly fixed flooring panels and I was wondering if movement could have caused a wire to become loose from a junction box under the floor? If so, surely my trusty tester screwdriver wouldn't find power at the light fitting?
I'm baffled and before I resort to calling out an electrician does anyone have any ideas?

Thanks

[ericmark]

Your screwdriver only tests for line wires and for light to work it also needs a neutral.

[alec]

Hi, I have a similar problem, except I don't have upstairs lights because I live in a bungalow. The hall, and 2 bedrooms lights suddenly stopped working. I was wondering, are they connected by a switch and therefore when one goes, they all go. All other lights are working fine - 1 bedroom, living room, kitchen and bathroom. The hall has 2 switches, 1 at the front door and one just outside the living room. I have disconnected all the ceiling fittings, will I have to put them all back on to test if they are working? Any help will be much appreciated.