184
Driving and Driving Safety The events below inform the driver of PSM control
operations and warn him to adapt her/his driving
style to the road conditions:
– The multi-functional information light in the
instrument panel lights up.
– Light in the PSM Off button flashes.
– Hydraulic noises can be heard.
– The vehicle decelerates and steering-wheel
forces are altered as the PSM controls the
brakes.
– Reduced engine power.
– The brake pedal pulsates and its position is
changed during braking.
In order to achieve full vehicle deceleration,
foot pressure must be increased after begin-
ning of the brake pedal pulsing.
Examples of PSM control operations
– If the front wheels of the vehicle drift on a
corner, engine power is reduced and the rear
wheel on the inside of the corner is braked if
necessary.
– If the rear of the vehicle swings out on a
corner, the front wheel on the outside of the
corner is braked.– Brake system prefilling:
The brake system is prepared for possible sub-
sequent emergency braking if the accelerator
pedal is released suddenly and quickly.
The brake system is prefilled and the brake
pads are already applied gently to the brake
discs.
– Brake booster:
In the event of an emergency braking operation
where the pedal force is insufficient, a brake
booster provides the braking pressure neces-
sary for maximum deceleration at all 4 wheels.
Combined use of PSM and PTM/PTM Plus
In order to ensure optimal stabilization of the ve-
hicle, the center differential lock (PTM) and possib-
ly the rear differential lock (PTM Plus) are also
opened when PSM interventions occur.
Tip on driving
When PSM is switched off, wheel-specific brake in-
terventions and the traction control system (TCS)
are also inactive.
The automatic brake differential (ABD) remains on.Off-road PSM
(PSM in Low Range program)
When Low Range is active, an off-road PSM
specially matched to off-road driving is activated
to enhance traction.
In order to improve driveability on difficult terrain,
the response of the off-road PSM is less sensitive
in the low speed range when the vehicle is opera-
ted in the Low Range off-road driving program.
If the brakes are highly stressed, the automatic
brake differential (ABD) switches itself off to
protect the brakes. It remains deactivated until the
brake system has cooled sufficiently.
Engine drag torque control
In conditions of excessive slip, the engine drag
torque control system prevents all driven wheels
from locking up when the car is passing. This is
also the case for downshifts on a slippery road.
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Driving and Driving Safety
185
Switching off PSMfPress PSM OFF button A.
PSM is switched off after a short delay.
The light-emitting diode in the button is lit up.
When the PSM is switched off, the multifunctio-
nal PSM light on the instrument panel is lit and
a message appears in the multi-purpose dis-
play of the instrument panel.During braking, the vehicle is stabilized even
when PSM is switched off.
One-sided spinning of the wheels is prevented,
even with PSM switched off.
PSM should always be switched on during
“normal” driving.
However, it can be of advantage to switch off PSM
temporarily in exceptional situations:
– On a loose surface or in deep snow
– When “rocking the vehicle free”
– When using snow chains.
Vehicles with Tiptronic: When the PSM is
switched off the slip monitoring function is also
deactivated.– The multifunctional light on the instrument pa-
nel lights up for a lamp check when the ignition
is switched on.
– The light indicates a control operation, inclu-
ding when PSM is switched off (brake control
in the event of one-sided wheel spin).
– In conjunction with the multi-purpose display on
the instrument panel, the light indicates that
PSM is switched off.
– Faults are displayed by the light in conjunction
with the multi-purpose display of the instru-
ment panel.
PSM is out of order.
fConsult your authorized Porsche dealer.
Multifunctional PSM light
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186
Driving and Driving Safety Collapsible spare wheel
fNever switch the PSM off when driving with a
collapsible spare wheel.
To w i n g
fFor information on towing:
Please see the chapter “TOWING” on
Page 342.
Tip on driving
When PSM is switched off, wheel-specific brake
interventions and the traction control system
(TCS) are also inactive.
The automatic brake differential (ABD) remains on.
Switching PSM back onfPress PSM OFF button A.
PSM is switched on after a short delay.
The light-emitting diode in the button and the
multi-functional PSM light on the instrument
panel go out. A message is shown on the multi-
purpose display of the instrument panel.
ABS
(Anti-lock Brake System)
Warning!
In spite of the advantages of ABS, it is still the
driver’s responsibility to adapt her/his driving style
and maneuvers in line with road and weather
conditions, as well as the traffic situation.
The increased safety that is provided should not
induce you to take greater risks with your safety.
The limits set by the physics of driving cannot be
overcome, even with ABS.
Risks of accident due to inappropriate speed can-
not be reduced by ABS.
ABS ensures:
–Full steering control
The vehicle remains steerable
–Good driving stability
No skidding due to locked wheels
–Optimum braking distance
Shorter stopping distances in most cases
–Lock prevention
No flat spots on the tiresFunction
The decisive advantage of ABS is in the driving
stability and maneuvrability of the vehicle in
hazardous situations.
ABS prevents locking of the wheels during full
braking, on almost all road surfaces, until shortly
before the vehicle stops.
The ABS begins to control the braking process as
soon as a wheel shows a tendency to lock.
This controlled braking process is comparable to
extremely rapid cadence braking.
The pulsating brake pedal and a “rattling noise”
warn the driver to adapt her/his driving speed to
the road conditions.
fIf full braking should be necessary, press the
brake pedal all the way down throughout the
entire braking procedure, regardless of the
pulsating pedal. Do not ease up on pressure
applied to the pedal.
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Driving and Driving Safety
187
Warning light
If the ABS warning lights light up in the instrument
panel and on the multi-purpose display of the
instrument panel while the engine is running, the
ABS has switched off because of a fault.
In this event, the braking system will operate with-
out lock prevention,as in cars without ABS.
fAdapt your driving style to the changed
braking behavior.
fThe ABS must be checked immediately at an
authorized Porsche dealer. This is necessary
in order to prevent the occurrence of further
faults whose effects cannot be defined.
The ABS control unit is adjusted for the approved
tire dimensions.
The use of tires with non-approved dimensions can
lead to different wheel speeds, causing the ABS to
switch off.
Off-road ABS
(ABS in Low Range program)
When Low Range is active, an ABS specially
matched to off-road driving is activated automati-
cally.In the event of braking on loose ground, the per-
missible slip values for ABS braking are increased
so that the off-road braking distance is reduced
(wheels dig into the surface).
If the driver needs to steer, this off-road driving
program is automatically switched off to maintain
steerability.
Hillholder -
moving-off assistant on vehicles with
Tiptronic SIn Tiptronic selector lever positions D and M, the
hillholder function makes it easier to move off
from a standstill on an upward slope when the
engine is running. The driver does not have to
apply the brake.
The hillholder thus makes moving off on slopes
easier.
Danger!
Risk of accident, resulting in serious perso-
nal injury or death.
The vehicle can roll backwards if the Hillhol-
der is switched off.
fAlways apply the footbrake on slopes.Hillholder is not active:
– In Tiptronic selector lever positions N and R
– In the limp-home mode and
– If not all of the wheels are touching the ground
(on difficult terrain, for example).
Warning!
In spite of the advantages of the hillholder func-
tion, it is still the driver’s responsibility to adapt
her/his driving style and maneuvers in line with
situational conditions.
The increased safety that is provided should not
induce you to take greater risks with your safety.
The limits set by the physics of driving cannot be
overcome, even with the hillholder function.
Driving at the limits should be avoided, e.g., on icy
slopes or on slippery surfaces. In this and similar
cases, the support of the hillholder function is not
guaranteed.
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190
Driving and Driving Safety
Air Suspension with Level Control
and Height AdjustmentOn vehicles with air suspension, the driver can set
five different level steps manually.
The preselected level is automatically adjusted to
suit the vehicle speed.
The height of the car is automatically kept
constant when the vehicle is loaded.
Tip on driving
It is not permissible to drive on public roads with
the car in the terrain or special terrain setting.Note on operation
Frequent level changes can cause the compressor
to overheat. In this case, the compressor must
cool for several minutes before level adjustment is
fully functional again.
Normal levelThe ground clearance at normal level is around
8.5 in. (215 mm) (Cayenne, Cayenne S,
Cayenne S Transsyberia) or 7.68 in (195 mm)
(Cayenne GTS).Terrain levelThis setting is intended for off-road driving, field
paths and forest paths, etc.
The vehicle is raised by around 1 in. (26 mm)
compared to normal level.
Terrain level can be selected only manually at
speeds below around 50 mph (80 km/h).
The car is automatically lowered to normal level at
speeds exceeding around 50 mph (80 km/h).
The car is automatically raised to terrain level
when Low Range is activated.
Special terrain levelThis setting is intended only for extremely
challenging terrain requiring maximum ground
clearance. The vehicle is raised by around 2.2 in.
(56 mm) compared to normal level.
The warning light in the instrument panel
comes up when the special terrain level has been
reached.
Special terrain level can be selected only at
speeds below around 19 mph (30 km/h).
The car is automatically lowered to terrain level at
speeds exceeding approx. 19 mph (30 km/h).Low levelThis level is intended for high-speed driving. Above
speeds of around 78 mph (125 km/h), the car is
automatically lowered by around 1 in. (24 mm)
(Cayenne, Cayenne S, Cayenne S Transsyberia) or
0.4 in. (9 mm) (Cayenne GTS) compared to
normal level.
When the speed drops to below around 25 mph
(40 km/h), the car is automatically raised to
normal level.
Note
If low level was set manually with the rocker switch
in the center console, low level also remains
active at speeds below around 25 mph (40 km/h).
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192
Driving and Driving Safety Indication of selected level
The selected level is displayed by light-emitting
diodes beside the rocker switch (illustration).
The corresponding light-emitting diode beside the
rocker switch flashes during the control process.
The light-emitting diode is continuously lit after the
control process.
The level change is also indicated on the multi-
purpose display of the instrument panel.
Exceptions
Automatic changes from normal level to low level
and back are not indicated on the multi-purpose
display of the instrument panel.
Warning messageVarious messages are indicated on the multi-pur-
pose display of the instrument panel if there is a
system fault or if the compressor switches off due
to overload.
fFor further information on warning messages
on the multi-purpose display:
Please see the chapter “OVERVIEW OF
WARNING MESSAGES” on Page 149.
fAdapt your driving style to the changed condi-
tions.
fConsult an authorized Porsche dealer in order
to remedy a system fault.
fIf the overload-protection function causes the
compressor to switch off, wait for a time until
it has cooled down. The system will function
again as soon as it has cooled sufficiently.
The warning message appears when the control
system is switched off and when the collapsible
spare wheel is being filled. This does not indicate
a fault.
The warning message will go out once these
procedures have been completed.
Raising vehicle with the jackWhenever it is necessary to jack up the vehicle:
fManually set normal level and then switch off
level control.
Switching off level control
1. Switch ignition on.
2. Push rocker switch forward for 5 to
10 seconds.
A message is shown on the multi-purpose
display of the instrument panel.
The vehicle can now be raised.
Switching level control back on
1. Switch ignition on.
2. Push rocker switch forward for 5 to
10 seconds or
3. Drive forward with the vehicle.
Level control switches on automatically.Transporting the vehicles on car trains,
ferries and car transportersfTie the vehicle down only at its wheels.
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Driving and Driving Safety
193
Porsche Active Suspension
Management (PASM)Various messages are shown on the multi-purpose
display of the instrument panel.
fFor further information on warning messages
on the multi-purpose display:
Please see the chapter “OVERVIEW OF
WARNING MESSAGES” on Page 149.
Three different running-gear setups can be selec-
ted with the push of a button:
–comfort
–normal
–sport
If the running-gear setups “comfort” or “normal”
have been selected, the system automatically
changes the setup to “sport” when the car is dri-
ven in a sporty manner.
Indication of the selected running-gear
setupThe light-emitting diode in the button of the selec-
ted running-gear setup is lit.
In addition, the selected running-gear setup is indi-
cated on the multi-purpose display of the instru-
ment panel for around 12 seconds.
The warning light in the instrument panel comes
on if there is a system fault. A warning message is
shown on the multi-purpose display of the instru-
ment panel.
fAdapt your driving style to the changed condi-
tions.
fTo remedy the fault, consult an authorized
Porsche dealer.
Selecting the running-gear setup1. Switch ignition on.
2. Press the appropriate button.
Note on operation
The running-gear setup selected last is stored in
memory after the ignition is switched off.
Warning lights and warning
messages
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Driving and Driving Safety
197
Recommended procedure
fDeactivate the Low Range off-road driving
program.
fClean headlights and tail lights and check them
for signs of damage.
fClean the front and rear lincense plates.
fClean the tire tread with a jet of water and
remove any foreign objects.
fClean wheels, wheel housings and the under-
body with a jet of water.
fCheck whether the car has picked up plant
parts or branches.
These materials increase the risk of fire and
can damage fuel lines, brake hoses, boots of
the axle joints and drive shafts.
fAfter off-road driving, always check the entire
floor assembly, tires, body structure, steering
system, running gear and exhaust system for
signs of damage.fAfter driving for an extended period through
mud, sand, water or substances with a similar
soiling effect, check the brake discs, brake
pads, wheels and axle joints and have them
cleaned.
fIf you experience severe vibrations after
driving off road, check the wheels for foreign
substances.
These substances can produce an imbalance
which might be responsible for the vibrations.
Removing these deposits may remedy the
problem.
Uphill driving
Danger!
Danger of serious personal injury or death
and risk of damage if the vehicle should
overturn.
fDo not turn around when driving uphill.
fIf it is not possible to climb a gradient, the car
must be backed down in reverse gear.
fDo not drive over embankments or slopes at
steep diagonal angles.
fIf the vehicle starts to tilt, immediately steer in
the direction of the tilt (line of slope).
fWhen driving uphill, never let the vehicle roll
backward when in idle or not in gear.
Exclusive use of the footbrake is too risky in such situations.
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