I found the time today to see why it comes only so lukewarm from my ventilation jet passenger room (BiLev). For one thing, I changed the climate control unit because there were bad noises.
then to the main theme of these bellows plates ??? behind the middle console did not stand properly and so stuck on half BiLev so it came front window and lukewarm inside space.
I then exchanged it for another same problem and then for a 3rd also the same the two work 100%.
Now I have found that to put so ne art spring is there and this goes quite tight and so can not open at all for BiLev.
Now finally my question how do I get to the box where the flap is in for the switch to BiLev front fan so I can see if there might be. a other spring is defective. One time, it banged like something broke up.
By hand it can still be changed to BiLev but only with extreme spring back pressure but when it is stopped comes again a nice airflow out of the front nozzles
.If can help me like I do it best instead.
im bild hab ich markiert was klemmt bzw. den gegendruck vorzugsweise diese feder macht das Problem. 
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