2004 jag xj vandenplas; my fuel light keeps coming on, and the fuel needle drops to empty; then after about 15 minutes, or if I drive over 70mph for a few minutes, the needle goes back to full and the light goes out. Could that be a bad fuse, and if so which fuse(engine, trunk,interior), or is the fuel pump bad?

 

I would suspect the continuity of the wiring vetween the tank sender unit and the instrument cluster (IC) - maybe a connector needs jiggling or cleaning? Alternatively there could be a fault in the sender itself.

Important be dead careful when checking this, because although in practise the IC is pretty robust, from personal experience they are easily wrecked by voltage spikes, which would cause you great grief and cost! Always disconnect the battery whilst doing anything involving the instrument cluster. You'll need to re-set the windows afterward (down until it clicks, then up until it clicks) and probably also re-input the radio code.

Ps. I have just noticed your vehicle, and my reply refers to the x100 (particularly as far as the windows is concerned).

MODERATOR - should this be moved to the correct forum?