Porsche Cayenne V6 2008 Service Information page 70

Chassis
Page 4.4
PDCC is an active roll stabilization system, which records the vehicle's
lateral inclination during cornering right from the start and reduces this
considerably. This is done using active anti-roll bars on the front and
rear axle, which ensure stabilization torques on both axles.
This means that the active anti-roll bars build up specific forces to coun-
teract the lateral inclination of the vehicle, depending on the steering
lock and lateral acceleration. PDCC reduces the vehicle's lateral inclina-
tion by up to 2.5° compared with a vehicle without PDCC. This improves
performance due to improved wheel/road contact.
At the same time, PDCC also records uneven road surfaces (bumps) and
can compensate for these by evaluating sensor data from the chassis
and speed. This significantly improves driving comfort on various types
of road surfaces.
The sensor data is evaluated continuously and appropriate control oper-
ations are initiated over the vehicle's entire speed range in order to
guarantee the horizontal positioning of the vehicle at all times. One
sided destabilizing impulses caused by long undulations in the road
surface (so-called copying of rolling motion) can be significantly
reduced.
PDCC also offers additional driver benefits for off-road driving. Active
anti-roll bar control in conjunction with an integrated surface detection
system reduces body movements considerably, thereby ensuring signifi-
cantly improved comfort. The best possible traction on various road
surfaces is particularly important for off-road driving. When the driver
activates Low Range mode using the rocker switch on the center
console, PDCC switches to off-road mode. The swivel motors are
enabled in this mode so that the vane controllers in the housing can turn
freely and the anti-roll bar halves are decoupled. This results in
maximum axle articulation. To prevent instability at higher speeds and
during dynamic maneuvers in Low Range mode, the control system is
activated again depending on vehicle speed
Transmission Driving Mode
High Range On-road mode
Low Range Off-roadmode
Low Range Off-road mode
Low Range Off-road mode
Vehicle Speed PDCC
0-Vmax. Continuous control
<7.3 mph (35km/h) Anti-rollbars can turn
freely for max. axle
articulation
7-35 mph (35-55km/h) Stabilizing action
> 35 mph (55km/h) Continuous control