Interior light fault

So I have looked around but no one seems to have had issues with this fault so I’m asking. Should be fairly straight forward but I can’t figure it out.

So I will admit, other than a Jeep Wrangler TJ I owned for a year and had to sell over lockdown, this is the most modern car I have owned, having only classic VW’s before this (yes as daily drivers).

So to me the 2004 v8 disco seems like the starship enterprise of sophisticated electronics and I started fault finding my interior lights and it’s got me screaming “why is this not working”.

I have owned the car for 13 days and 10 days of that was isolation On returning to the uk. It’s not had working interior lights since I owned it but with some cleaning and bulb attention I have got the curtesy lights when the doors are opened etc to work on all three lamps. But the “switched on” positions on front and rear doesn’t work but does in the middle.

I have taken them all out and cleaned the connections, checked the feed with a multi meter and even tried to connect them to the battery directly and I can’t work them out. There seems to be no feed unless the door switches are activated but I don’t know why.

why would my middle light work when switched “on” and my front and rear won’t, they must all work of the same feed and be earthed the same etc right?.

I don’t have any manuals yet sorry so any help please.

In my experience with vehicle lighting, there’s a positive and a negative and a switch, if you were lucky enough to get one in old bug or bus.

So that all said.

what fuses do the lights operate on, it would seem there are maybe two circuits and two fuses one for “on” and one for “doors open/exit vehicle”. Can someone explain how they work?.

How are they earthed so I can check there, they must have a permanent live different earth thing going on as well if they don’t work on all functions, on off and doors?

The courtesy lights have permennent live and they are switched on with earth through the switch or by the BCU on automatic action. As long as they all work automatically when the doors are opened the problem is local for those which are not working as the bulb doesnt get earth for some reason, bad switch or missing earth on the black wire, connect earth with a wire where the black wire goes at the cluster and see what happens, download the diagrams and electrical library from here https://www.dropbox.com/sh/47hbz40an5he5j2/AACH509eV_o7QhM5PoX6eFVLa

How do I use the wiring diagrams you very kindly linked to find the location. I found the earthing point number but couldn’t find the actual location in vehicle like header earth 0706 Above

thanks

Open the "Electrical library" file and there you have "connector views" and click on the proper one in this case C0706

It was an earth issue and all fixed now!!!. Very happy to have that stupid issue fixed.
Thanks Sierrafery that’s two things you helped me fox today.

well done...this was a joyful day then

There is always more yo fix