Damaged wiring

[JohnW2]

It would be worth the op seeing if there is a joint just above the light fitting, perhaps in connector blocks, just in case there happens to be a bad joint there ...

Agreed.

- as I'm not sure if it was ever confirmed if the cable actually was damaged in the wall.

I'm pretty sure that it has never been confirmed, hence reinforcing the point above. Indeed, the fact that 'hitting the wall' has an effect could just as well be due to bad connections in a hidden JB as to a 'damaged cable'. I wonder if the OP has tried 'hitting the ceiling'?

Kind Regards, John

 

[CrazyFool]

Thanks for the prompt response.

See video for behind the light switch and light fitting:

The simple test would be to runs a temporary wire from the porch neutral to your light and bang away to see if it makes a difference. I suggest having both lights on while doing that to ensure the porch is good.

However if it indicates the passage neutral is bad you will still have to lift more floor boards to get to the junction box because you NEED to establish the fault is not more widespread than just the one light.

I've not got cable long enough to bring the neutral from the porch light for our test.
Can I take a neutral from a plug socket just to diagnose if there is an issue with the light neutral?

Thanks again

CF

 

[sparkwright]

Definitely no connections above the hole in the ceiling where the light is?

 

[CrazyFool]

Definitely no connections above the hole in the ceiling where the light is?

Definitely not.
I've lifted floor boards directly above.
I know exactly where the junction box is where the ceiling rose is contained and its a mission getting to it.

I don't have a multimeter im afraid.

I can pull a neutral from a nearby plug socket as a qualitative test if you like.

 

[sparkwright]

It's not that hard to lift up a corner of carpet and lift a floorboard, if you can determine where the junction box may be.

Are there any connector blocks at the back of the light switch?

 

[sparkwright]

'Borrowing' a neutral from the sockets may not work, if you have RCDs at the mains.

 

[sparkwright]

Also, is that an ES (screw in) lampholder?

These can go wrong, the contacts can fail to make contact.

CHECK THIS TOO.

 

[CrazyFool]

So I got an extra long cable and connected the porch neutral to the passage light neutral.
Doing this makes the light work!

So we know what the problem is... the neutral at the passage light has gone.

Let me know your thoughts.

CF

 

[JohnW2]

... So we know what the problem is... the neutral at the passage light has gone. ... Let me know your thoughts.

A loose/poor/broken connection in a junction box, wherever it is, is probably far more likely to be the problem than is any 'cable damage'.

Kind Regards, John

 

[CrazyFool]

A loose/poor/broken connection in a junction box, wherever it is, is probably far more likely to be the problem than is any 'cable damage'.

Kind Regards, John

I agree.
I just can't get to this junction box because it will mean destroying half of my sons bedroom.

I'm taking some solace in knowing the electrics in the rest of the house works perfectly, not even a flicker. If it was a loose live wire I would have to find it but am I right in thinking a disconnected neutral wire to the light is just a blank wire buried under the floorboards?
It has no active connections to anything or anywhere.

I would like to cap off the current switch live and 'neutral' and start afresh by taking a permanent live and neutral from the porch.

What do you guys think?

CF

 

[sparkwright]

You say you know exactly where the junction box is.

Can you cut a neat hole in the ceiling below, and possibly cover with a blank plate or even a smoke detector for now?

There doesn't seem any real need to replace the live wire, you only need a neutral from one point of that lighting circuit.

It does raise the question of that junction box with a broken wire floating about, which is not good.

Obviously we are only assuming it's in the junction box.

Is there a way of disconnecting the neutral from somewhere else, without disconnecting anything from the rest of the lighting circuit? Probably not if the junction box has two or more 'supply' cables.

Are you certain the neutral wire isn't some how broken at the light where you can see?

 

[sparkwright]

Of course, it's not definite the neutral is broken inside the junction box, if it was branched off a nearby downstairs light, there is a possibility there could be a broken wire in there.

Just thinking out aloud, so to speak.

It COULD be anywhere...

 

[CrazyFool]

The neutral wire looks mint close to the light fitting. Thats not the problem.

I know where the junction box is but not exactly within a margin of error that I would want to cut through the ceiling and insulation to get to it. Good shout though.

Please can you elaborate on the below, I'm not really understanding you:

Is there a way of disconnecting the neutral from somewhere else, without disconnecting anything from the rest of the lighting circuit? Probably not if the junction box has two or more 'supply' cables.

Of course, it's not definite the neutral is broken inside the junction box, if it was branched off a nearby downstairs light, there is a possibility there could be a broken wire in there.

Many thanks
CF

 

[sparkwright]

I just wondered if by some chance the feed to the junction box happened to be ONE cable that was tapped off another in another room.

If so, that cable could be disconnected from there.

Unlikely.

Are you able to see how many cables are in this junction box from the floorboards you have up?

Or is it too far away?

 

[CrazyFool]

Aah ok.
I couldn't see the junction box to answer your question but what you're suggesting is unlikely.

Where do we go from here?
Shall I just cap off the switch live and the dead neutral cable and call it a day?