2010 PORSCHE 911 GT3 Owners Manual

56
Operation, Safety
Brake booster The brake booster assists braking only when
the engine is running.
When the car is moving while the engine is not
running, or if the brake booster is defective, more
pressure on the brake pedal is required to bring
the car to a stop.
If this happens, ABS and PSM will also not
operate.
Moisture or road salt on brakes affects braking.
Brakes will dry after a few cautious brake applica-
tions.
Warning!
Risk of an accident, resulting in serious
personal injury or death.
Driving through water may reduce the
traction.
Moisture on brakes from road water, car
wash, or coating of road salt may affect
braking efficiency.
fCautiously apply brakes to test brakes after exposure to road water, etc.
Brake wear Your car has excellent brakes, but they are still
subject to wear. The rate at which they wear
depends on how the brakes are used.
fHave the brake system inspected at the
intervals recommended in your Maintenance
Booklet.
Brake system warning light
You can check the functionality of the brake
system warning light by switching the ignition to
the “On” position and verifying that the warning
light illuminates.
If the warning lights in the instrument panel and on-
board computer stay on when the engine is
running or come on while driving, the brake pads
are worn excessively.
fDo not continue to operate the vehicle.
Have your authorized Porsche dealer inspect
or replace the brake pads.
Brake pads Wear on the brake pads and brake discs depends
to a great extent on the driving style and the condi-
tions of use and therefore cannot be expressed in
actual miles on the road.
The high-performance brake system is designed
for optimal braking effect at all speeds and tempe-
ratures.
Certain speeds, braking forces and ambient
conditions (such as temperature and humidity)
therefore might cause “brake noises”. This also
applies after completion of the breaking-in period
required for the new brake components.
New brake pads or linings
New brake pads and brake discs have to be
“broken in”, and therefore only attain optimal
friction when the car has covered several hundred
miles or km.
The slightly reduced braking ability must be
compensated for by pressing the brake pedal
harder. This also applies whenever the brake pads
and brake discs are replaced.
Warning light USA
Warning light Canada
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Operation, Safety
57
ABS Brake System
(Antilock Brake System)The ABS system represents a major contribution
to the enhancement of active safety in your
vehicle. This system prevents the wheels from
locking in a panic stop on almost all road
surfaces. With the ABS system in your vehicle, the
following areas are enhanced: Steering, vehicle remains steerable under all
braking forces when ABS is engaged.
Good directional control, no swerving caused
by locking of wheels under braking conditions.
Shorter stopping distance, stopping distances
are usually reduced because controlled braking is
maximized.
Prevention of wheel lock up, no brake-induced
sliding and thus no localized tire wear from
emergency braking.
The crucial advantage of the ABS system over a
conventional brake system is in the area of
maintaining directional control and maneuverabi-
lity of the car in emergency situations.
Warning!
The increased control that is provided should
not induce you to take greater risks with your
safety. The limits dictated by the laws of
physics cannot be overcome, even with ABS.
The risk of accidents due to inappropriate
speed cannot be reduced, even by the ABS.
The driver bears the responsibility for all
driving maneuvers.
fAdapt your driving style to the prevailing road
and weather conditions.
fObey all traffic laws.
Other vehicles not equipped with the ABS
system may not be able to maintain control,
especially on wet or poor road surfaces and
thus may be more likely to impact you from
behind.
fTo minimize that risk, use your ABS system to
increase your ability to maneuver to avoid
dangerous situations and not merely to try to stop in the shortest distance possible.
Operation of the ABS systemA wheel speed sensor is mounted to each of the
four wheels. If wheel lock-up of either of the front
wheels or the rear wheels is sensed during
braking, the brake pressure is adjusted automati-
cally until the wheel no longer slips.
If braking forces approach the wheel lock-up point
for all wheels (panic braking) the ABS system will
intervene to provide a rapid rythmic braking. The
proper operation of ABS is perceived by the driver
as a pulsating brake pedal in conjunction with
audible noise and perhaps some vibration.
fIf you experience these sensations while
driving or a road surface with questionable
traction, reduce vehicle speed appropriate for
the prevailing 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.
The functional readiness of all the main electrical
components of the ABS is checked by an
electronic monitoring system both before and
while you drive.
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58
Operation, Safety When the ignition is switched on the ABS warning
light will light up while the system is electronically
interrogated and goes out when the engine is
started if the check is not yet complete.
If the ABS warning lamp fails to go out, this
indicates that ABS has been deactivated due to a
fault. If the warning lights in the instrument panel
and on-board computer light up while you are
driving, this indicates that a fault has occurred. In
both cases, normal braking, as in vehicles without
ABS, is still retained.
The ABS system should, however, be examined at
an authorized Porsche dealer immediately to
prevent the occurrence of further faults.
fIf the ABS system becomes inoperative, take
your vehicle to your authorized Porsche dealer
immediately.
Warning!
Risk of an accident, resulting in serious
personal injury or death.
The control unit of the ABS brake system is
set for standard tire size. If non-standard
tires are installed, the control unit may misin-
terpret the speed of the vehicle, because of
the variant data it receives from the sensors
on the axles.
fUse only tire makes and types tested by Porsche.
Warning light USA
Warning light Canada
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Operation, Safety
59
Porsche Stability Management
(PSM)PSM is an active control system for stabilization of
the vehicle during extreme driving maneuvers.
Warning!
Risk of an accident, resulting in serious
personal injury or death.
The increased control that is provided should
not induce you to take greater risks with your
safety. The limits dictated by the laws of
physics cannot be overcome, even with PSM.
The risk of accidents due to inappropriate
speed cannot be reduced, even by PSM.
The driver bears the responsibility for all
driving maneuvers.
fAdapt your driving style to the prevailing road
and weather conditions.
fObey all traffic laws.
Sensors at the wheels, brakes, steering system
and engine continuously measure:
–Speed
– Direction of travel (steering angle)
– Lateral acceleration
– Rate of turn about the vertical axis
– Longitudinal accelerationPSM uses these values to determine the direction
of travel indicated by the driver.
PSM intervenes and helps to correct the course if
the actual direction of motion deviates from the
chosen course (steering-wheel position):
It brakes individual wheels as needed. In addition,
the engine power may be manipulated in order to
stabilize the vehicle.
The events below inform the driver of PSM control
operations and warn him/her to adapt his/her
driving style to the road conditions:
– The multifunctional information light on the
instrument panel flashes.
– Hydraulic noises can be heard.
– The vehicle decelerates and steering-wheel
forces are altered as 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 the
brake pedal has begun vibrating.
Advantages of PSM– Improved traction and lane-holding ability in all
driving situations – even on road surfaces with
varying friction.
– The system compensates for undesired lateral
vehicle reactions when the driver releases the
accelerator pedal or brakes when cornering.
This compensation functions up to the
maximum lateral acceleration.
– PSM actively helps stabilize the vehicle as
required during dynamic driving maneuvers
(e.g. rapid steering movements, during lane
changes or on alternating bends).
– Improved braking stability in curves and on
different or varying road surfaces.
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60
Operation, Safety Readiness for operation
PSM is switched on automatically every time you
start the engine.
PSM should always be switched on during
“normal” driving.
However, it may make sense to switch off PSM
temporarily in exceptional situations, for example:
– On a loose surface or in deep snow,
– when “rocking the vehicle free” and
– when using snow chains.
Switching off PSMPSM can be switched off in 2 stages:
– Stage 1 SC OFF:
Switch off Stability Control (SC).
– Stage 2 SC+TC OFF:
Also switch off Traction Control (TC).
Danger!
There is a risk of accident due to loss of
control of the vehicle. There is no stabilizing
brake control in either switch-off stages
(even when the brakes are used).
fPSM should always be switched on during
“normal” driving. This particularly applies in wet conditions.
Switching off Stability Control (SC)Precondition:
The light-emitting diode in the SC+TC OFF button
must be off.
fPress SC OFF button.
Stability Control is switched off after a short
delay.
The light-emitting diode in the button is lit up.
When the system is switched off, the multi-
functional PSM light on the instrument panel
is lit and the message “SC OFF” appears
continuously on the on-board computer.
An acoustic signal also sounds.
– When Stability Control is switched off, sportier
Traction Control is activated.
– Brake control is deactivated.
– The ABS remains active.Switching Stability Control (SC) back onfPress SC OFF button.
Stability Control 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.
The on-board computer shows a message.
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Operation, Safety
61
Switching off Stability Control (SC) and
Traction Control (TC)fPress SC+TC OFF button.
Stability Control and Traction Control switch off
completely after a short delay.
The light-emitting diode in the button is lit up.
When the system is switched off, the multifunc-
tional PSM light on the instrument panel is lit
and the message “SC+TC OFF” appears conti-
nuously on the on-board computer.
A gong signal also sounds.
fPush the on-board computer lever forward to
acknowledge the additional message under
the digital speedometer.– All PSM functions are deactivated.
– The ABS remains active.
Note
If the PSM is deactivated directly using the
SC+TC OFF button, the light-emitting diode of the
SC OFF button also lights up.
Switching Stability Control (SC) and
Traction Control (TC) back onfPress SC+TC OFF button.
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.
The on-board computer shows a message.
– The multifunctional light on the instrument
panel lights up for a lamp check when the
ignition is switched on.
– The light flashes to indicate PSM control
operations.
– In conjunction with a message on the on-board
computer, the light indicates that PSM is fully
or partially deactivated.
An acoustic signal also sounds.
– The light indicates a fault in conjunction with a
message on the on-board computer.
PSM is out of order.fHave the fault repaired at your authorized
Porsche dealer immediately.
fPlease see the chapter “PUTTING VEHICLE
INTO OPERATION” on Page 218.
TowingfPlease see the chapter “TOWING” on
Page 235.Checks on test standsBrake tests must be performed only on plate-
type test stands or roller test stands.
The ignition must be off.
The following limit values must not be exceeded
on roller test stands:
– Testing speed 5 mph (8 km/h)
– Test duration 20 seconds
Handbrake tests on the brake test stand must
only be carried out with the ignition switched
off.
Power measurement
Power measurements on roller test stands are not
approved by Porsche.
Multifunctional PSM light
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62
Operation, Safety
Sport modeWhen the Sport mode is switched on, the exhaust
gas back pressure in the lower and middle ranges
is reduced in the variable exhaust system. This
serves to produce a marked increase in torque in
the engine speed range from approx. 3000 rpm
and 4000 rpm. The best values for vehicle accele-
ration and low-end torque are achieved when
Sport mode is switched on.
Switching Sport mode on and off
fPress button in the centre console.
When Sport mode is switched on, the light-
emitting diode in the button is lit.
Note on operation
After the ignition is switched off, Sport mode is
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Operation, Safety
63
The previously selected PASM mode is always
activated after the engine is started.
There is no automatic return to Normal mode after
the ignition is switched off.
PASM makes two running-gear setups available to
the driver: “Normal” and “Sport”.
The selection is made via a button on the center
console.
When in Normal mode the running gear is in a
basic setup for roads and circuits with “irregular”
surfaces.
Sport mode provides a shock-absorber setting
for particularly high driving dynamics (e.g. on level
circuits).
The variable suspension system selects the appro-
priate damping level for each wheel according to
the situation and conditions of driving.
Example:
If the vehicle is driven in a very sporty manner in
Normal mode, PASM automatically adapts the
shock-absorber behavior to the driving situation
accordingly.
Switching on PASM Sport modefPress PASM button in the center console.
When PASM Sport mode is switched on, the
light-emitting diode in the button is lit up and a
message is shown on the on-board computer.Switching off PASM Sport modefPress PASM button in the center console.
The light-emitting diode in the button goes out
and the on-board computer displays a
message.
Dynamic Engine Mounting (PADM)The dynamic engine mounting with variable
damping is a system for improving driving
dynamics and enhancing driving comfort.
Depending on the driving situation, the ideal
mounting stiffness and damping is automatically
selected in a range between an almost rigid
connection of the engine to the body (improved
driving dynamics) and a decoupling of the engine
from the body (improved driving comfort).Warning messageDynamic engine mounting faults are indicated by
a warning message on the on-board computer.
fPlease see the chapter “WARNINGS ON THE
INSTRUMENT PANEL AND THE ON-BOARD
COMPUTER” on Page 148.
Porsche Active Suspension
Management (PASM)
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