my heater was only working at 4 on the fan, then went to full blast on all settings 1-4 then stopped. found on the e34net web site that this is a common problem and the "sword" resitor thing under the dash needs replacing. I did that and got another but still not working...now it just blows the fuse under the hood in the fuse box. The dealership thought possibly it could be the heater motor blown also. Has anyone encountered this problem before if it's common? how can I access the heater fan to disconnect and see if the fuse keeps blowing.

Any advise or experience would be much appreciated!

I did the thing you tryed and mine was fixed, but I wasn't blowing fuses... If you need the controls, let me know I have a set that I would sell pretty cheap. sorry I can't help you out.