guys my 2001 x5 3.0i suddenly stopped blowing air on the front. AC works because I could feel the cold air coming out from the rear vents, just not enough air flowing out from the front. It's weird because the AC control panel all lights up and appears to be working, it's just that when you press the 3 directional buttons it doesn't appear to have any effect. Is there a self test I could do to figure out if it's a vent motor issue?