My interior lights (2xcabin1xboot space) were working completely perfectly but were giving off poor levels of light. I decided to change them over to LED's with built in ballast as per the many threads on the forum.

All worked fine for a week, but then all stopped working completely at the same time.

I checked the 7.5A fuse, F17 in the box in the passenger footwell and all is fine.

Changed bulbs back to original filiment festoon, and still nothing works.

Any clues??

I checked the fuse by taking it out and using the beep continuity setting on my multimeter, which did indeed beep. So I can be sure the fuse is still intact.

UPDATE.

Tested fuse again and saw power at each of the exposed pins when in the fuse holder, continuity was there when tested away from the car.

Anyway, tried a new 7.5A and as if by magic, the lights work!!!

All i can assume is that there is enough flow left in the fuse for a continuity test or no draw voltage test, but when under load the fuse just breaks open inside. When I was testing I did see the fuse 'flicker' through the plastic. So this would indicate a very fine break in the fuse arcing across I guess.

Moral of story, for the benefit of the forum, a non load tested fuse is a non tested fuse!!!

Thats certainly worth knowing and bearing in mind.

Just had the same problem but without trying LED's was going to ask if there is a separate fuse as the list doesn't show one in my handbook for interior lights, will try F17 in the morning. MY14 TD4 manual XS Orkney grey.

MY11 TD4 Manual XS Lago Grey, privacy glass, rear spoiler, full ebony leather,rear seat entertainment. Gone
2001/51 plate Disco TD5 GS. Gone
95 N Disco TDi300. Gone

You do get a dodgy fuse now and again I've known them look perfect but just not work.

Well looked at Fuse 17F it's 5amp, the fuse box cover graphics show it as a door symbol with a key in the centre so I guess it's not that one although I changed it for one of the spares - no difference. Anyone have a definitive list for MY14 RHD fuses? MY14 TD4 manual XS Orkney grey.

MY11 TD4 Manual XS Lago Grey, privacy glass, rear spoiler, full ebony leather,rear seat entertainment. Gone
2001/51 plate Disco TD5 GS. Gone
95 N Disco TDi300. Gone