i am out of warranty currently and started having issue w/ my 06 525i. the fan on/off switch turns on automatically every time you turn the car on and then makes some rattling sound (almost like a tapping or so) for 3 to 5 sec and then goes away. i have had issus w/ the knob before but it was different as it would come on intermittently when driving over a bump or harsh roads and the delaer fixed that a year ago or so. this just seems to happen everytime I turn the car on, i would turn off the fan before turning the car off anf when irestart the fan is blowing again. please advice.

 

I had the same problem and the tech at my dealer had to remove the dash. When he did he found that the connector for the A/C was somewhat loose and was causing my system to come on and off randomly for no damn reason, (WHILE THE CAR WAS DRIVING).

However, the AC is supposed to turn on automatically when the car starts. This is normal and by design, for some..........stupid.........retarded reason. Even after I'd turn the car off with the A/C off it will come back on if I haven't been driving the car for about 1 hour. I guess computer resets to default after a certain time.


P.S. - Welcome to the forum and enjoy your stay! Make sure you post pictures and look at the albums. Before you know it you'll be broke but damn your car will look good!