Hi,
the airbox flap is controlled by
KFLUKL [load/RPM] at hex 1A906 "Kennfeld zur Steuerung der Luftfilterklappe"
TLUKL [sec] at hex 1A946 "Verzögerungszeit für Schließen der Luftfilterklappe"
and
VLUKL [km/h] at hex 1A947 "vfzg - Schwelle für Öffnen der Luftfilterklappe"
It is not documented in the ME7.1 Funtionsrahmen, because it is a special function only in the RS4.
I have also blocked my open airbox flap, because I want to use the implemented "intake air changeover function" to control a water methanol injection.
To do this, I will disconnect the harness connector from the N335 and plug it into a relay to switch a electrical high-pressure water pump.
The N335 is connected to pin 44 of the 551K ECU.
So I can control the pump by KFLUKL over load and RPM with a vehicle speed threshold.
I will do this in the next month, because I don't have time at the moment.