Porsche Cayman User Handbook Manual page 64

Porsche Stability Management
(PSM).
PSM, which comes as standard, is
an automatic control system that
stabilises the vehicle at the limits
of dynamic driving performance.
Sensors continuously monitor
driving direction, speed, yaw veloc-
ity and lateral acceleration. Using
this information, PSM computes the
actual direction of motion. If this
direction deviates from the desired
course, PSM initiates braking
interventions targeted at individual
wheels in order to stabilise the
vehicle.
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Under acceleration on wet or
low-grip road surfaces, PSM
improves traction using the ABD
(automatic brake differential)
and ASR (anti-slip regulation)
functions, giving an agile
response. When 'Sport' mode is
selected on the optional Sport
Chrono Packages (p. 62), the PSM
intervention threshold is raised to
enable greater driver involvement
– particularly at speeds of up to
approximately 70 km/h (45 mph).
The integrated ABS can further
reduce the braking distance.
For an even sportier drive, PSM
can be deactivated. However,
it is automatically reactivated for
your safety if either of the front
wheels (in 'Sport' mode, both
of the front wheels) requires ABS
assistance. ABD remains perma-
nently active. Two additional
functions of PSM increase safety
even further: precharging of the
brake system, and brake assist.
If you suddenly release the accel-
erator pedal, PSM automatically
readies the braking system. With
the braking system having been
precharged, the brake pads are
already in light contact with the
brake discs. Maximum braking
power is therefore achieved much
Cayman