My tail lights are not working the bulbs I replaced does anyone know where the fuse is for this.98 xj8l also my interior radio,clock and window control lights also not working.does anyone know where this fuse is located.I have a chart in the boot but they don"t list the word tail light or interior lights on it.

 

I don't know about the tail lights, but the interior lights are controlled by the Body Processor Module. The Body Processor Module gets power from several sources, but two that affect interior lights have fuses which are in the driver's side heelboard fuse box, fuses # 5 and 7, 15A. There is an upholstery panel under that side of the seat which, when pulled forward, reveals that fuse box. Note that there are FIVE fuse boxes in this car, two under the hood/bonnet, one each under the right and left rear seats, and one in the trunk/boot.

There are other more complicated possibilities, but a first step is to check these fuses.

 

I checked under drivers seat and there is no upholstery panel that I could see and the carpeting doesn't budge either. can you be any more specific on how to locate and open said box please?

 

Guess I wasn't clear enough. It's on the driver's side, under the front edge of the rear seat. There is a vertical rug-covered piece that is actually not part of the carpet, under the front of the rear seat. It's called a "heelboard" for obvious reasons I guess. Should be a plastic button in the middle towards the top. That button needs to be pried or twisted loose, and then the whole panel pried off. You need to get under its edges at the sides and bottom and pull forward.

There is a similar panel on the passenger side, with a different fuse box underneath.