2004 PORSCHE CAYENNE steering

Driving and Driving Safety
167
A- SET (Store speed)
1- RESUME - Switch on/resume cruise control readiness
(pull toward driver)
2- OFF - Interrupt (push away from driver)
3-+ SPEED - Accelerate (raise clockwise)
4-– SPEED - Decelerate (lower counter-clockwise)Cruise ControlCruise control maintains any selected speed
between 20 and 150 mph (30 and 240 km/h)
without you having to use the accelerator.
The cruise control is operated with the operating
lever on the steering wheel.
Warning!
Risk of accident while using cruise control in
heavy traffic and consequent personal injury
or death, on twisting roads or under
unfavorable road conditions (e.g. wintry or
wet conditions, varying road surfaces).
fDo not use the cruise control under such
conditions.
fObserve all local and national speed limits.
Risk of an accident, personal injury and loss
of control.
fDo not reach through the steering-wheel spokes while driving.
Switching cruise control readiness onfPull back the operating lever to position 1 until
it clicks audibly into place.Maintaining and storing speedfBring the car to the desired speed with the
accelerator.
fPress button A.
The desired speed has now been stored.
Accelerating (e.g. to overtake)Option 1
fIncrease the speed as usual with the accelera-
tor.
When you ease off the accelerator, the
previously stored value is set again.
Option 2
fPush operating lever upwards into position 3
until the desired speed is reached.
The speed reached is maintained and stored
when the operating lever is released.
Option 3
fPush operating lever slightly upwards into
position 3 (a maximum of 10 times).
The speed is increased by 1 mph (2 km/h),
each time the lever is pushed upwards.
Note on operation
Cruise control operation is automatically interrup-
ted if the speed is increased by more than approx.
16 mph (25 km/h) for longer than 20 seconds.
Cruise control readiness
The green indicator light on the tacho-
meter now indicates readiness.
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170
Driving and Driving Safety
Tiptronic SThe Porsche Tiptronic is a six-speed transmission
and features an “automatic” and a “manual” gear-
shift mode.
In automatic selection mode (selector lever po-
sition D), gear changing is automatic.
Depending on the driving program, you can
change temporarily from automatic to manual
mode using the rocker switches on the steering
wheel.
In manual selection mode (selector lever
position M), you change gear using the rocker
switches on the steering wheel or by pushing the
selector lever forward or back.
The functions of selector lever positions D and M
differ in the on-road program, High Range, and in
the off-road program, Low Range.
You can change between selector lever positions
D and M as you wish while driving.
The currently selected gear is retained if you
change from D to M.
If you change from M to D, the gear-changing map
suitable for your current driving style is selected
and the appropriate gear is selected.
Note on operation
Take care not to operate the rocker switches on
the steering wheel inadvertently, thereby trigger-
ing undesired gear changes.
Changing the selector lever positionThe selector lever is locked with the ignition key
withdrawn.
The selector lever can be moved from position P
or N only with:
– The ignition switched on
– The brake pedal pressed and
– The release button pressed (arrow).Release button
The release button (arrow) on the front side of the
selector lever prevents unintentional gear chan-
ges.
The release button must be pressed when shifting
to position R or P.
The selector lever cannot be operated in the event
of an electrical fault.
fPlease see the chapter “SELECTOR LEVER
EMERGENCY RELEASE” on Page 175.
StartingThe engine can be started only in selector lever
position P or N with the brake pedal pressed.Moving offfSelect the desired position for moving off
(D, M or R) only when the engine is idling and
when depressing the brake pedal.
fSince the car creeps when in gear, do not re-
lease the brake until you want to move off.
fAfter selecting a gear, do not accelerate until
you can feel that the gear is engaged.
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172
Driving and Driving Safety The corner is taken in the right gear, and when you
accelerate out of the corner you do not have to
change down.
Shifting gear on the steering wheel
By shifting gear with the rocker switches on the
steering wheel, you can temporarily change from
automatic selection mode D to manual selection
mode M.
Advantages:
– Shifting down before corners and on entering
congested areas, on downward slopes (engine
braking) or for brief spurts of acceleration.
– Selecting 1st or 2nd gear for moving off.
The manual selection mode remains engaged:
– For cornering (depending on the lateral
acceleration) and passing,
– When the vehicle is stationary (e.g. at a
junction).
The system leaves manual selection mode:
– automatically after around 8 seconds
(unless car is cornering, passing or
stationary),
– if you depress the accelerator to kickdown.Temporary change-down
Precondition:
– Speed is higher than approx. 33 mph
(54 km/h).
fDepress accelerator quickly.
The Tiptronic changes temporarily to the
sportiest gear-changing map, i.e. to the
highest possible gear-changing points.
Correspondingly, the transmission shifts down
immediately by one, two or three gears.
Ending the function
fRelease the accelerator markedly (by approx.
25%).
Kickdown
The kickdown function is active in selector lever
position D.
fFor optimum acceleration, e.g. when over-
taking, depress the accelerator pedal beyond
the full-throttle point (kickdown).
The transmission shifts down depending on the
speed of travel and engine speed.
Upward shifts occur at the highest possible engine
speeds.
These gear-changing speeds remain active until
the accelerator is released to approx. 80% of the
full-throttle position.
D - Automatic selection mode (in the off-
road driving program)fUse selector lever position D for “normal”
driving.
The gears are shifted automatically according
to the accelerator position and speed.
The gear-changing points have been adjusted to
achieve the best possible vehicle control on diffi-
cult terrain.
Depending on the route profile, the gear-changing
points are shifted towards higher or lower engine-
speed ranges. On steep downhill stretches,
upward shifts are prevented until medium engine
speeds are reached (at least 2,500 rpm).
When the car is passing, an automatic upshift
does not occur when the engine speed limit is
reached.
Shifting gear on the steering wheel
By shifting gear with the rocker switches on the
steering wheel, you can temporarily change from
automatic selection mode D to manual selection
mode M.
Advantages:
– Shifting down on downward slopes (engine
braking) or for brief spurts of acceleration.
– Selecting 1st/2nd or 3rd gear for moving off.
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182
Driving and Driving Safety
Warning!
In spite of the advantages of PTM or four-wheel dri-
ve, 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 situ-
ation.
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 PTM or four-wheel drive.
Risks of accident due to inappropriate speed
cannot be reduced by PTM.Porsche Traction Management (PTM)Porsche Traction Management is a full-time all-
wheel control system designed to influence the
longitudinal and lateral dynamics. It is closely
linked with the Porsche Stability Management
(PSM) system:
PTM ensures the best possible power distribution
to the four driven wheels at the front and rear
axles. The system realizes this optimal traction by
intervening in the lock control function of the trans-
fer case and rear differential. PTM is active at all
times and, unlike the PSM, cannot be switched off.Advantages of PTM
– Obvious improvement in traction, driving
stability and steering ability of the car.
– Vehicle is more manageable when driven at its
performance limits.
– Improved straight-ahead tracking and stability.
– The aforementioned features allow for a
sportier setup of the running gear.
– The TCS and ABD provide even better traction
for all wheels.
Full-time all-wheel drive
With the four-wheel drive, the drive power is
variably distributed to the front and rear wheels.
Power distribution and wheel speed compensation
between the front and rear axles is realized with a
transfer box.
Distribution of the drive power depends on the
wheel speed difference between the two axles.
The transfer box always controls power distribu-
tion in such a way that optimal propulsion is achie-
ved, even on an unfavorable road surface.
Full-time four-wheel drive ensures optimal handling
and greater stability.Automatic brake differential (ABD)
The ABD system controls the front and rear axles
separately. If one wheel of an axle starts to spin,
it is braked so that the other wheel on the same
axle can be driven.
The ABD recognizes different driving states, and it
features control strategies adapted to these
states. In situations in which little propulsive power
is required, such as when the car moves off on a
level gravel surface, traction control already
becomes active at low engine speeds. If great
propulsive power is required, e.g. when moving off
on an uphill slope or for rapid acceleration, the
ABD is adapted accordingly.
A special off-road program is used in Low Range
mode.
Traction control system (TCS)
The traction control system prevents the wheels
from spinning by adjusting the engine power,
thereby ensuring good lane-holding ability and a
stable driving behavior.10_Cayenne_21_KW17.book Seite 182 Donnerstag, 9. April 2009 3:33 15

Driving and Driving Safety
183
Porsche Stability Management (PSM)PSM is an active control system for stabilization of
the vehicle during extreme driving maneuvers. It
operates together with the Porsche Traction
Management (PTM) system.
PSM makes use of both the ABD and TCS
systems, as well as the known functions of the
anti-lock brake system (ABS) and engine drag
torque control system (MSR).
Warning!
In spite of the advantages of PSM, 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 PSM.
Risks of accident due to inappropriate speed
cannot be reduced by PSM.Advantages of PSM
– Best possible traction and lane-holding ability
in all driving situations – even on road surfaces
with varying friction.
– The system compensates for undesired vehi-
cle reactions (load-alteration effect) when the
driver releases the accelerator pedal or brakes
on bends. This compensation functions up to
the maximum lateral acceleration.
– PSM actively stabilizes the vehicle as required
during dynamic driving maneuvers (e.g. rapid
steering movements, during lane changes or
on alternating bends).
– Improved braking stability on corners and on
different or varying road surfaces.
– Improved brake functioning and reduced
stopping distance in the event of emergency
braking.Readiness for operation
PSM is switched on automatically every time you
start the engine.
Function
Sensors at the wheels, brakes, steering system
and engine continuously measure:
– Driving speed
– Direction of travel (steering angle)
– Lateral acceleration
– Longitudinal acceleration
– Rate of turn about the vertical axis
PSM uses these values to determine the direction
of travel desired by the driver.
PSM intervenes and corrects the course if the
actual direction of motion deviates from the
desired course (steering-wheel position):
It brakes individual wheels as needed. If neces-
sary, PSM additionally influences the engine power
or the gear-changing characteristic of the
Tiptronic in order to stabilize the vehicle.
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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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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
195
Off-Road DrivingPlease read this chapter carefully before driving
off road with your Porsche.
The information provided will familiarise you with
the special advantages of your vehicle, allowing
you to arrive at your destination safely every time.
We recommend practicing on less rugged terrain.Vehicles with SportDesign package
Caution!
Risk of damage. On vehicles with Sport-
Design package, front, rear, and side
member trim are painted. Off-road driving
can seriously damage these trim parts.
fWhen driving off-road, make sure these parts
are not damaged.
fMake sure there is sufficient clearance
between obstacles and the underside of the
vehicle.
fAvoid driving through water.
fDo not use side member trims or rear wheel spoilers as a running board.Maintenance Note
Please bear in mind that off-road driving subjects
all vehicle components to considerably more wear
than normal use, making professional inspection
and maintenance after each use a vital precondi-
tion for functioning and safety.
Grains of sand, dirt particles and other abrasive
materials entering the brakes can cause exces-
sive wear or unpredictable braking action.
Rules for off-road drivingfEnsure vehicle is equipped with approved all-
terrain tires.
fPay attention to the ground clearance of the
vehicle.
Please see the chapter “GROUND
CLEARANCE” on Page 357.
fActivate Low Range.
Please see the chapter “SELECTING OFF-
ROAD DRIVING PROGRAM” on Page 178.
fStow or fasten luggage and loads securely.
Please see the chapter “LOADING
INFORMATION” on Page 231.
fIf unknown terrain is obscured from view,
examine it on foot first and traverse it with
extreme caution.
This way, obstacles are easier to recognize
and damage to the vehicle is avoided.fAlways drive with the engine running.
Power steering assistance is provided only
with the engine running.
fDrive slowly and uniformly.
fAlways make sure that the wheels touch the
ground.
fBefore driving through water, check the water
depth, the condition of the surface beneath it
and the speed of the water.
fLook out for obstacles such as boulders,
holes, tree stumps or ruts.
fAlways keep the sliding/lifting roof or
Panorama roof system and the side windows
closed while driving.
fDo not depart from marked routes or paths.
fRespect Nature.
Always obey off-limits signs.
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