Possible cause of fault

WARNING: This page is about a different car, the 2006 Porsche Cayenne, 2005 Porsche Cayenne, 2004 Porsche Cayenne, and 2003 Porsche Cayenne. However, it is still accessible from the selected car via links, so may be relevant.

Short circuit to B+ in the wiring of pin 83 of the level control module (electrical fault in electric circuit)
Short circuit to ground in the wiring of pin 83 of the level control module (electrical fault in electric circuit)
Open circuit in one or more wires connected to pins 65, 76 and 83 of the level control module (electrical fault in electric circuit)
Level control module receives implausible signal from vehicle level sensor
If implausible signal is received from vehicle level sensor, perform calibration, refer to 43 K2 CALIBRATION - AS OF MY 2003 (ALL MODELS EXCEPT CAYENNE S TIO TITAN) .
Vehicle level sensor faulty
Level control module faulty