There are 2 possibilities:
a) the levers are broken of the vanes
b) the stepper motors are off=bracket for the stepper motors are broken.
Here some general info
http://bmwe32.masscom.net/johan/ihka/ihka.html
Here a pic from my collection
http://img357.imageshack.us/my.php?i...einheit1gt.jpg
For the stepper motors bracket, you can either make an easy fix with a plstic strip/clip, or replace it
http://bmwe32.masscom.net/johan/cent...ts_v1.1-1.html