i'm interested in buying this 735i i saw but i told the seller i want to know how much it's going to cost to get it fixed none of the auto climate control features seem to work. i think it's just one chip or computer thing that controls it all. what my question is it common for climate control to go out on this car and is it just one thing to replace and how much is it and where i can buy it.(pardon my bad grammer). if you know where i can order the parts then e-mail me the links and awnsers to my questions thankx.

There is no chip in there, just a bunch of switches and a sliding mechanism. You can take the whole thing apart and get it working again, but there are lots of little parts and springs, so think twice if your all thumbs. This is a common problem with these cars. Search the archives and you'll find lots of info on fixes and cost to replace. The other items which seem to cause problems are the auto transmissions and the instrument cluster. The auto tranny needs the fluids changed to keep it healthy, and all the instrument clusters have a board in the back with a battery that will eventually leak acid if it is not replaced. Both of these problems are common to all the BMWs of this era, not just the 7's.
Mark

Its a pain to pull out the climate control unit but its probably worth it. I had the same problem as you described. The culprit was the circuit board. Two of the traces on the board were damaged. Once repaired, the climate control unit was back to its old self again. Good luck.