[Erich]

Die korrekte Hoehe ist doch im Bentley Reparaturhandbuch angegeben fuer Niveauregulierung und abhaengig von der Felgengroesse:
Bentley table for LAD equipped cars as follows:
Wheels Rear ride height
15 inch 522 +/-3 mm (20.55 +/- 0.4 inches)
16 inch 529 +/-3 mm (20.93 +/- 0.1 inches)
17 inch 545 +/-3 mm (21.46 +/- 0.1 inches)

Ride height is measured from the lower edge of the wheel arch to the bottom edge of the wheel rim (not the ground).

Allerdings steht da nichts von M-Federn.

Fehlermeldung ist normal wenn alles in der Luft haengt, sollte aber erst nach 8 Minuten kommen, siehe unten = Camber Warning Switch

Auszug aus der englischen Info:

Camber Warning Switch (E32 AND E34 Touring)
The self-leveling suspension systems used in the E32 and the E34 Touring are equipped with a camber warning switch. The switch is mounted on the right rear axle support and connected through a rod to the semi-trailing arm.
The function of the switch is to warn the driver of an overload condition or an unsafe driving situation.
If the switch detects a rear wheel camber of -3.5 degrees a signal is sent to the check control module and displayed on the dash. A time delay of 8 minutes is incorporated to prevent the warning from being displayed while driving through turns. The E38 does not use the camber warning switch due to the design of the rear suspension.