get to the dealer and change your battery. it happened to me before. everything on the instrument cluster display went dead, abs on and the car started just fine. a friend of mine who is a mechanic but not a bmw mechanic didn't know what was wrong with it, it took him like 2 hours searching for blown fuse and lose connection. by that time, i had to go somewhere. i ran it to the dealer, they look at it and say. replace the battery. $300 later, everything is back to normal. what they did was replace the battery, reset the computer, reflash the software or something. problem sovled. your dying or dead battery could cause numerous electronics problems make you think that some modules are failing, but its actually not. well the dying battery may be caused by some electronics power drain make sure you know there is nothing is draining the battery.

__________________
2002 X5 3.0 Siena Red
Premium, Cold Weather, Rear Climate Packages, 19" Wheels
Aluminum Running Boards, Clear Tail Lights, Clear Side Markers
Titanium Kidney Grills, Titanium Trunk Lid, Xenon Headlights
4.6is X5 exhausts, 35% Tint, Aluminum Pedals
2005 530I Mystic Blue
Premium Package, Sport Package, Xenon Headlights
18" Sport Wheels, 35% Tint all around
Mods to come: M-Tech Front Bumper, M5 Side Skirts, M5 Rear Bumper
Quad Exhausts, Style 172 19" Wheels