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 18 of the level control module
Short circuit to ground in the wiring of pin 18 of the level control module
Open circuit in the wiring of pin 18 of the level control module
Spring strut valve faulty
Level control module faulty

NOTE: If multiple valve faults (fault code 0806, 0807, 0808) or another relay fault (fault code 1399) are recorded, check the system's plug connections for correct contacts.