2005 PORSCHE 911 CARRERA warning

60
Controls, Instruments If the warning lights in the instrument panel and on-
board computer go on while driving, the brake flu-
id level may be too low, or (if the brake pedal travel
has increased) one of the two brake circuits may
have failed.
A greater braking pressure will be required, stop-
ping distances will be longer and the braking be-
havior will change, particularly in curves.
With correctly adjusted brakes, and a correctly
working brake system, the pedal travel to the
point of brake actuation should be 1-3/16 in. to
1-9/16 in. or 30 to 40 mm.
Whenever the brake pedal travel exceeds this dis-
tance, have the brake system checked.
Brake pedal
Warning!
Risk of an accident.
Any obstruction of the brake pedal could
increase the stopping distance.
fAlways check the movement of the brake pedal
before driving and make sure that it is not ob-
structed by a floor mat or any other object.
fSecure the floor mat to prevent it from sliding
into positions that could interfere with the safe
operation of your vehicle.
Your Porsche dealer will be glad to offer you nonskid floor mats of the correct size.
Note
In case one of the two brake circuits fails, in-
creased pedal travel is required to bring your
vehicle to a full stop.
Warning!
To avoid overheating and premature wear of
the brakes:
fBefore descending a steep grade, reduce
speed and shift the transmission into a lower
gear or driving position to control speed.
fDo not “ride the brakes” by resting your foot on
the pedal when not intending to apply brake
pressure.
fDo not hold the pedal down too long or too
often.
This could cause the brakes to get hot and not function properly.
Brake warning light USA
Brake warning light Canada

Controls, Instruments
61
Brake booster The brake booster assists braking only when
the engine is running.
When the car is moving while the engine is not run-
ning, or if the brake booster is defective, more
pressure on the brake pedal is required to bring
the car to a stop.
Moisture or road salt on brakes affects braking.
When the vehicle is driven on salted roads for ex-
tended periods, the brakes should be washed
down thoroughly about every 2 weeks. An auto-
matic carwash facility cannot do this job properly.
Brakes will dry after a few cautious brake applica-
tions.
Warning!
Driving through water may reduce the trac-
tion.
Moisture on brakes from road water, car
wash, or coating of road salt may affect
braking efficiency.
fCautiously apply brakes to test brakes after being exposed.
Brake wear Your car has excellent brakes, but they are still
subject to wear. The rate at which they wear de-
pends on how the brakes are used.
fHave the brake system inspected at the
intervals recommended in your Maintenance
Booklet.
If the warning lights in the instrument panel and on-
board computer stay on when the engine is run-
ning 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 con-
ditions 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 tem-
peratures.
Certain speeds, braking forces and ambient
conditions (such as temperature and humidity)
therefore might cause “brake noises”.
New brake pads or linings
New brake pads and brake discs have to be “bro-
ken in”, and therefore only attain optimal friction
when the car has covered several hundred miles
or km.
The slightly reduced braking ability must be com-
pensated 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

62
Controls, Instruments
ABS Brake System
(Antilock Brake System)The ABS system represents a major contribution
to the enhancement of active safety in your vehi-
cle. 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 emer-
gency braking.
The crucial advantage of the ABS system over a
conventional brake system is in the area of main-
taining directional control and maneuverability of
the car in emergency situations during normal driv-
ing, including panic braking in turns.
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 dan-
gerous situations and not merely to try to stop in the shortest distance possible.

Controls, Instruments
63
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 brak-
ing, the brake pressure is adjusted automatically
until the wheel no longer slips. The brake pressure
is regulated for each front wheel individually and
for both of the rear wheels together.
On a road surface which is slippery on only one
side, the rear wheel which is braking on the slip-
pery surface determines the brake pressure which
will be applied equally to both rear wheels. This en-
sures that directional stability is maintained. How-
ever, 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 driv-
ing or a road surface with questionable trac-
tion, reduce vehicle speed appropriate for the
prevailing road conditions.
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. 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 indi-
cates 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 driv-
ing, 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 pre-
vent the occurrence of further faults.
fIf the ABS system becomes inoperative, take
your vehicle to your authorized Porsche dealer
immediately.
Warning!
The control unit of the ABS brake system is
set for standard tire size. If non-standard
tires are installed, the control unit may mis-
interpret 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

Controls, Instruments
65
Porsche Stability Management
(PSM)PSM is an active control system for stabilization of
the vehicle during extreme driving manoeuvres.
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 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. Advantages of PSM – Superior traction and lane-holding ability in all
driving situations – even on road surfaces with
varying friction.
– PSM actively stabilizes the vehicle during dy-
namic driving maneuvers (e.g. rapid steering
movements, during lane changes or on alter-
nating curves).
– Improved braking stability in curves and on dif-
ferent or varying road surfaces.
Readiness for operationPSM is switched on automatically every time you
start the engine.FunctionSensors at the wheels, brakes, steering system
and engine continuously measure:
–Speed
–Steering angle
– Lateral acceleration
– Rate of turn about the vertical axis
– Brake pressure
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. 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 to adapt his driving style
to the road conditions:
– The multi-functional information light on the
instrument panel lights up.
– 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 the brake pedal pulsing.
f f f

Controls, Instruments
67
Sport modeA sportier car set-up is obtained when Sport mode
is switched on. PSM interventions are later than in
Normal mode; the vehicle can be manoeuvred
with greater agility at its performance limits,
without the need to dispense with the assistance
of PSM in emergency situations. This helps to
achieve optimal lap times, particularly on race
circuits and a dry road surface. – The multifunctional light on the instrument
panel lights up for a lamp check when the
ignition is switched on.
– The light indicates a control operation by
flashing, including when PSM is switched off
(brake control in the event of one-sided wheel
spin).
– In conjunction with a message on the on-board
computer, the light indicates that PSM is
switched off.
An acoustic signal also sounds.
– Faults are displayed by the light in conjunction
with a message on the on-board computer.
PSM is out of order.
fPlease consult an authorized Porsche dealer.
fPlease observe the chapter “PUTTING
VEHICLE INTO OPERATION” on Page 239.
fPlease observe the chapter “WARNINGS ON
THE INSTRUMENT PANEL AND THE ON-
BOARD COMPUTER” on Page 105.
TowingfPlease observe the chapter “VEHICLE
TOWING” on Page 259.Checks on test standsWhen carrying out brake tests on roller test
stands a maximum testing speed of 5 mph
(8 km/h) must not be exceeded.
Handbrake checks on the roller brake tester
must be performed only with the ignition switched
off.
Multifunctional PSM light

72
Controls, Instruments
Ignition/Starter Switch with anti-
theft Steering LockThe ignition lock has a total of four ignition lock po-
sitions.
The ignition key rebounds to the initial position
from every ignition lock position.
fFor your safety, fasten safety belts.
fPlease observe the chapter “IMMOBILIZER” on
Page 19.
fPlease observe the chapter “KEY WITH RADIO
REMOTE CONTROL” on Page 20.
Before starting the enginefApply the footbrake.
fManual transmission:
Move the gearshift lever into neutral.
The clutch pedal must be depressed fully
before the starter will engage.
fTiptronic:
Move the selector lever to P or N.Switch position 0 Initial position
The ignition key cannot be withdrawn when the
ignition is switched on or when the engine has
been started.
To withdraw the ignition key:
fStop the vehicle.
fOn vehicles with Tiptronic S:
Move selector lever to position P.
fSwitch ignition off.
fRemove ignition key.
Switch position 1 Ignition on
fTurn ignition key to position 1.
Ignition is switched on.
Note on operation
All electrical equipment can be switched on.
fPlease observe the chapter “WARNINGS ON
THE INSTRUMENT PANEL AND THE ON-
BOARD COMPUTER” on Page 105.

Controls, Instruments
73
Switch position 2Start engine
fTurn ignition key to ignition lock position 2.
fPlease observe the chapter “STARTING PRO-
CEDURES” on Page 74.Switch position 3Ignition off
fTurn ignition key to ignition lock position 3.
Locking the steering columnAutomatic locking
The steering column is automatically locked when
the ignition key is withdrawn from the ignition lock.
Warning!
Risk of an accident.
The steering wheel will lock and will cause
loss of steering.
fNever remove key from the ignition lock or turn
the key off while the vehicle is moving.
fAlways withdraw the ignition key when leav-ing the vehicle.Automatic unlocking
The steering column is automatically unlocked
when the ignition key is inserted into the ignition
lock.
Note
fTo avoid battery run-down, always remove the
ignition key from the ignition lock.
Please observe the chapter “BATTERY” on
Page 236.
Gong If you leave the key in the ignition/steering lock, a
gong will sound when the driver’s door is opened.
This is a reminder to remove the key.