Same happened to me, told that i needed a new cpu, at a full cost of €1300 all in. Ha, boiled down to a single 5 amp fuse (€0.45 each), which we found out ourselves, after the local dealer was not able to find and correct the problem. (but charged us all the same)
Switch on the engine, rev up to 3000rpm all systems should work again, if so check fuse number F27 (screen washer water motor), this could be the cause. If it is, keep a supply of them, much cheeper than a new cpu! Then just to check, engine off, remove the fuse, restart engine, if old problems come back, this is my answer.
Gav, December 2005