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Transmission and Chassis Control SystemsYour Porsche features a complex integrated system made up of all control systems acting in power transmission and in the chassis.
All control systems are networked with the aim of combining the best possible driving performance with maximum safety.
The following systems are invo lved, depending on equipment:
System/designation Scope
PTM
Porsche Traction Management – Active all-wheel drive with electronically
regulated map-controlled multiple-disc clutch
PSM
Porsche Stability Management – Driving stability control
– Anti-lock brake system (ABS)
– Brake system prefilling
– Brake booster (Hydraulic Brake Assist)
– Automatic brake differential (ABD)
– Anti-slip control (ASR)
– Engine drag torque control (MSR)
– HOLD function: standstill management
Air suspension
with level control and height adjustment – Full load-bearing air-spring stru
ts with integrated shock absorbers
– Height adjustment with Low Level setting in “S port Plus” mode and High Level setting for
maneuvering
PAS M
Porsche Active Suspension Management – Shock absorber system with adaptive, continuous shock absorber control
PDCC
Porsche Dynamic Chassis Control – Active chassis control system to stabilise
roll tendency of vehicle body when driving
– Controlled rear differential lock
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Porsche Traction Management
(PTM)Porsche Traction Management is an active all-
wheel control system designed to influence
longitudinal and lateral dynamics. It is closely
linked with the Porsche Stability Management
(PSM) system.
The permanently driven rear axle enhances the
vehicle’s sporty features. Drive power is
distributed fully variably to the front axle,
depending on the driving situation.
In conjunction with PSM, the PTM system ensures
perfect distribution of power among all four
wheels in every driving situation. This improves
traction and driving stabil ity and ensures the same
high level of agility and dynamic response.
Warning!
In spite of the advantages of PTM and four-wheel
drive, it is still the driver’s responsibility to adapt
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 greate r risks with your safety.
The limits set by the physics of driving cannot be
overcome, even with PTM or four-wheel drive.
Risk of accidents due to inappropriate speed
cannot be reduced by PTM or four-wheel drive. Advantages of PTM
– Clearly perceptible improvement in traction,
driving stability and steering ability of the
vehicle.
– Vehicle is more manageable when driven at its performance limits.
– Improved straight-ahead tracking and greater stability.
– More sporty vehicle setup while making full use of all the advantages of four-wheel drive.
– ASR and ABD further enhance traction for all wheels.
For information on ASR and ABD:
f Please see the chapter “PORSCHE STABILITY
MANAGEMENT (PSM)” on page 202.
Porsche Stability Management
(PSM)PSM is an active control system for stabilisation of
the vehicle during extreme driving maneuvers.
It operates together with the Porsche Traction
Management (PTM) system provided the vehicle is
fitted with the relevant equipment.
PSM makes use of both the ABD and ASR
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 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.
Risk of accidents due to inappropriate speed
cannot be reduced by PSM.
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– Brake system prefilling:
The brake system is prepared for possible
subsequent 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 (Hydraulic Brake Assist): In the event of an emergency braking operation
where the pedal force is insufficient, a brake
booster provides the braking pressure
necessary for maximum deceleration at all
4wheels.
Combined operation of PSM and PTM
In order to ensure optimum stabilisation of the
vehicle, torque distribution between the front and
rear wheels is adapted and the rear differential
lock is controlled on vehicles with PDCC.
In the event of a PTM fault, PSM cannot be
switched off.
If PSM is switched off, it is switched on again
automatically. 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.
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 vehicle moves off on
a level gravel surface, traction control already
becomes active at low engine speeds. If a large
amount of propulsive power is required, e.g. when
driving off on an uph
ill slope or for rapid
acceleration, the ABD system is adapted
accordingly.
Anti-slip control (ASR)
The anti-slip control system prevents the wheels
from spinning by adjusting the engine power,
thereby ensuring good lane-holding ability and
stable handling.
Engine drag torque control (MSR)
In conditions of excessive slip, the engine
drag torque control system prevents all driven
wheels from locking up when the vehicle is
overrunning. This is also the case for downshifts
on a slippery road.
Switching off PSMf Press button for at least 1 second.
PSM is switched off after a short delay.
The indicator light on the button and the
PSM OFF warning light on the instrument
panel light up.
The warning “PSM off” appears on the
multi-function display in the instrument panel.
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“Sport” and “Sport Plus” Mode FunctionThe selectable chassis settings mean that the
vehicle can offer various modes for a sportier
overall setup.
When “Sport” or “Sport Plus” mode is selected, all
the vehicle’s control systems are intentionally
shifted towards greater agility and driving
performance:
– PASM (Porsche Active Suspension Management) is automa tically changed to
“PASM Sport” or “PASM Sport Plus” mode,
resulting in a stiffer suspension setup.
The vehicle switches to Low Level in “PASM
Sport Plus” mode.
f Please see the chapter “PORSCHE ACTIVE
SUSPENSION MANAGEMENT (PASM)” on
page 208.
– Just like PASM, PDCC is switched to the corresponding “Sport” or “Sport Plus” mode,
whereby the rolling movements of the vehicle
are reduced further, depending on the
selected mode.
f Please see the chapter “PORSCHE DYNAMIC
CHASSIS CONTROL (PDCC)” on page 211.
– The PDK transmission switches to a sporty gear-changing map and shortens the gear
shifting times when Sport mode is activated.
Gear changes take place faster. f
Please see the chapter ““SPORT” AND “SPORT
PLUS” MODE” on page 195.
– The electronic accelerator pedal reacts sooner, and the engine is more responsive to
throttle inputs. When Sport mode is switched
on and the vehicle is travelling at a speed of
less than 25 mph (40 km/h), this function is
activated only after the driver has floored the
accelerator pedal or released it briefly.
– The rpm limiter characteristic is “harder”. In other words: the engine is immediately
throttled when the performance limits are
reached (only in manual selection mode on
vehicles with PDK).
– The turbo overboost briefly increases the engine boost pressure in the engine speed
range from 2,500 rpm to approx. 4,000 rpm.
As a result, torque in this speed range is
increased by 70 Nm (52 ftlb.). This
considerably improves acceleration and
flexibility, particularly in the medium engine
speed range. This does not affect the
maximum power. Quickly flooring the
accelerator pedal acti vates turbo overboost
in the engine control system. Overboost has
an effective operating time of approx.
10 seconds. After this time, it can be re-
activated by quickly flooring the accelerator
pedal again. – PSM (Porsche Stability Management) control is
more sporty in “Sport Plus” mode. PSM
interventions are later than in Normal mode.
The driver can maneuver the vehicle with
greater agility at it s performance limits,
without having to dispense with the assistance
of PSM in emergency situations. This helps to
achieve optimal lap times, particularly on race
circuits with a dry road surface.
f Please see the chapter “PORSCHE STABILITY
MANAGEMENT (PSM)” on page 202.
– Adaptive cruise control regulates speed and distance more dynamically.
– The Auto Start Stop function is deactivated.
f Please see the chapter “AUTO START STOP
FUNCTION” on page 169.
– The rear spoiler extends earlier and retracts later (“Sport Plus” mode only).
f Please see the chapter “RETRACTABLE REAR
SPOILER” on page 214.
– The system switches from High Level.
f Please see the chapter “HIGH LEVEL” on
page 209.
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Switching “Sport” mode on and offfPress button .
When “Sport” mode is switched on, the
indicator light on the button lights up.
The word “SPORT” appears on the digital
speedometer.
A sporty gear-changing map is enabled and the
gear shifting times ar e shorter for the PDK
transmission.
A sporty driving style is recognized more quickly
and the gear-changing speeds are adapted to
driving performance.
Braking downshifts are initiated earlier. Downshifts
occur for small decelerations, even at higher revs.
Switching “Sport Plus” mode on and offf Press button .
When “Sport Plus” mode is switched on, the
indicator light on the button lights up.
The words “SPORT PLUS” appear on the digital
speedometer.
In "Sport Plus" mode, the PDK transmission
changes to a shift progra m designed for driving
on race circuits. 7th gear is not selected.
The gear-changing performance is enhanced
significantly again compared with Sport mode.
The turbo overboost function (brief torque
increase at full throttle) is activated on vehicles
with the Sport Chrono Turbo package.
“Sport”/“Sport Plus” and
“PASM Sport”/“PASM Sport Plus” mode Switching “Sport” or “Sport Plus” mode on and off
simultaneously activates and deactivates the
corresponding PASM mode (“PASM Sport” or
“PASM Sport Plus”).
The PASM mode can be sw itched manually if you
want to use the characteristics of “Sport” or
“Sport Plus” mode, but prefer a more comfortable
chassis setup.
f Press button (repeatedly).
The indicator light for the selected chassis
setup on the button lights up.
In addition, the selected chassis setup is
shown on the multi-function display in the
instrument panel for approx. 4 seconds.
For information on PASM:
f Please see the chapter “PORSCHE ACTIVE
SUSPENSION MANAGEMENT (PASM)” on
page 208.
Storage, Luggage Compartment and Roof Transport System
233
A- Front carrier, long
B -Rear carrier, short
C -Cover trims
D - Torque wrench
E - Roof channel protectors
F -KeyFitting the roof transport systemWhen fitting the roof transport system for the first
time, the front and rear carrier must be adjusted
according to the width of the vehicle.
Roof channel protectors can also be secured to
the vehicle when fitting the roof transport system
for the first time. These protectors make it easier
to fit the roof transport system and protect the
fastening recesses in the roof rails from damage. 1. Open the cover flap on the roof rails.
2. Unscrew plastic screws from the retaining
threads.
f Make sure not to lose the plastic screws.
Note
When you have removed the roof transport
system, the plastic screws can be screwed back
into the retaining threads to prevent dirt from
getting into the threads. 3. Position the long carrier
A at the front and
the short carrier B at the rear loosely on the
fastening recesses.
f Fastening screws on the carriers must not
protrude underneath as this would damage
the vehicle.
f Make sure that the carriers are aligned in
accordance with the specifications on the
stickers on the underside of the carriers.
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Storage, Luggage Compartment and Roof Transport System
4. Remove the handle of the torque wrench D.
5. Loosen screws on the underside of
the carriers using the short side of the
torque wrench.
The carriers can be adjusted to fit the width
of the vehicle.
f Once you have adjusted the width of the
carriers, tighten the screws again using the
short side of the torque wrench. 6. Lift up the carriers slig
htly and fit roof channel
protectors E into the mounts on the underside
of the carriers.
7. Remove protective film from the bonding areas of the roof channel protectors.
f Check that the fastening recesses on the
roof rails are perfectly clean and free of
dust and grease. 8. Carefully fit the carriers into the fastening
recesses.
The roof channel protectors E are bonded
permanently into the fastening recesses.
These protect the paintwork in the fastening
recesses during repeated fitting of the roof
transport system and make fitting easier.
9. Unlock the cover flaps with the key.
10.Fold the cover flaps up fully.
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235
11.Tighten the fastening screws on the
carriers using the torque wrench F until the
arrow markings on the torque wrench are
perfectly aligned. 12.Fold the cover flaps on the carriers down
fully and slide the desired attachment into
the carriers. 13.Cut the cover trims
C to size and slide them
sideways into the carriers or press them into
the carriers from above to protect from
moisture and dirt.
14.Lock the cover flaps.
Repeated fitting of the roof transport system
Steps 5 to 7 can be omitted when the roof
transport system is fitted on the same vehicle
again.