The right front tire has been loosing air slowly but surely traditionally and at least for more than a year, ending up in a tire with doubtful quality.
Anyhow, the car has a working Central Tire Inflation System, helping us dealing with the problem temporarily. (Technical comment one year later: The problem was a defect in a small rubber ring located in the T-valve connecting the tube to the rest of the CTIS.)
Für manche Probleme gibt’s auch nette Lösungen: Der vordere rechte Reifen verliert – wie wir mittlerweile wissen wohl traditionell – Luft.
Zum Glück funktioniert die Reifenfüllanlage, das bleibt so trotzdem kein Dauerzustand.