I have a 2005 Mini Cooper convertible (not the S) All of a sudden, the battery, the power steering & Service Engine Soon lights all came on and the temperature guage went completely hot and the overheating light came on. I thought i was overheating so I turned the heater on full blast while I got off the freeway but the air never got hot. I pulled over and the radiator fluid resevoir was filled to the top and the fluid was boiling. About 10 minutes later, the fluid quickly dissapeared but it wasnt leaking. The power sterring fluid was very low. I filled the radiator resevoir and power steering fluid & waited till it cooled. I tried starting it and it would not start and only clicked loudly and the lights flashed on and off. I got the battery tested and it was bad. I replaced it and tried to drive it home. after two miles of driving, again the temp guage went all the way hot and the same lights came on.

Computer problem? Electrical? Any advice would be great!