2007 MERCEDES-BENZ SLR CLASS brake

83 Safety and Security
Driving safety systems
BAS
The Brake Assist System (BAS) operates in
emergency situations. If you apply the
brakes very quickly, the BAS automatically
provides full brake boost, thereby poten-
tially reducing the braking distance.
Apply continuous full braking pressure
until the emergency braking situation is
over.
The ABS will prevent the wheels from
locking.
When you release the brake pedal the
brakes function again as normal. The BAS
is then deactivated.
ESP®
The Electronic Stability Program (ESP®) is
operational as soon as the engine is run-
ning and monitors the vehicle’s traction
(force of adhesive friction between the
tires and the road surface) and handling.
The ESP
® recognizes when a wheel is
spinning or if the vehicle starts to skid. By
applying brakes to the appropriate wheel
and by limiting the engine output, the ESP
®
works to stabilize the vehicle. The ESP® is
especially useful while driving off and on
wet or slippery road surfaces. The ESP
®
also stabilizes the vehicle during braking
and steering maneuvers.
The ABS/ESP
® warning lamp v in the
instrument cluster (
page 29) flashes
when the ESP® is engaged.
The ABS/ESP
® warning lamp v in the
instrument (
page 28) cluster comes on
when you switch on the ignition. It goes out
when the engine is running.
Warning!G
If the BAS is malfunctioning, the brake sys-
tem is still functioning normally, but without
the additional brake boost available that
BAS would normally provide in an emergen-
cy braking maneuver. Therefore, the braking
distance may increase.
Warning!G
BAS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking efficiency beyond that af-
forded by the condition of the vehicle brakes
and tires or the traction. The BAS cannot
prevent accidents, including those resulting
from excessive speed in turns, following an-
other vehicle too closely, or hydroplaning.
Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of a BAS
equipped vehicle must never be exploited in
a reckless or dangerous manner which
could jeopardize the user’s safety or the
safety of others.

84 Safety and Security
Driving safety systems
For more information, see the
“Practical hints” section (
page 300).
Warning!G
Never switch off the ESP® when you see the
ABS/ESP® warning lamp v flashing in
the instrument cluster. In this case proceed
as follows:

While driving off, apply as little throttle
as possible.

While driving, ease up on the
accelerator.

Adapt your speed and driving style to
the prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The ESP
® cannot prevent accidents
resulting from excessive speed.
Warning!G
The ESP® cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded. The ESP
®
cannot prevent accidents, including those
resulting from excessive speed in turns, or
hydroplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The ca-
pabilities of an ESP
® equipped vehicle must
never be exploited in a reckless or danger-
ous manner which could jeopardize the
user’s safety or the safety of others.
!Because the ESP® operates automatically,
the engine must be shut off (SmartKey in starter
switch position 0 or1) when

the parking brake is being tested on a brake
test dynamometer

the vehicle is towed with the front axle raised
Active braking action through the ESP
® may
otherwise seriously damage the brake system
which is not covered by the Mercedes-Benz
Limited Warranty.
The ESP
® will only function properly if you use
wheels of the recommended tire size
(
page 381).

85 Safety and Security
Driving safety systems
Electronic traction system
The electronic traction system is a compo-
nent of ESP
®.
The electronic traction system improves
the vehicle’s ability to utilize available trac-
tion, especially under slippery road condi-
tions by applying the brakes to a spinning
wheel.
When you switch off the ESP
®, the elec-
tronic traction system is still enabled.Switching off the ESP
®
To improve the vehicle’s traction, turn off
the ESP® in driving situations where it
would be advantageous to have the drive
wheels spin and thus cut into surfaces for
better grip such as:

when driving with snow chains

in deep snow

in sand or gravelWhen you switch off the ESP
®

the ESP® does not stabilize the vehicle

the engine output is not limited, which
allows the drive wheels to spin and
thus cut into surfaces for better grip

the electronic traction system will still
apply the brakes to a spinning wheel

the ESP® continues to operate when
you are braking
Warning!G
If you are driving too fast, the electronic
traction system cannot reduce the risk of an
accident.
The electronic traction system cannot pre-
vent the natural laws of physics from acting
on the vehicle.
Warning!G
The ESP® should not be switched off during
normal driving other than in the circum-
stances described below. Disabling of the
system will reduce vehicle stability in
standard driving maneuvers.
Warning!G
Switch on the ESP® immediately if the
aforementioned circumstances do not apply
anymore. Otherwise the ESP
® will not stabi-
lize the vehicle when it is starting to skid or
a wheel is spinning.
iWhen the ESP® is switched off and one or
more drive wheels are spinning, the ABS/ESP®
warning lampv in the instrument cluster
flashes. However, the ESP
® will then not
stabilize the vehicle.

86 Safety and Security
Driving safety systems
The switch is located on the lower part of
the center console.
1ESP
® switch
Press ESP® switch1.
The ABS/ESP
® warning lampv in
the instrument cluster comes on.
The ESP
® is deactivated.
Switching on the ESP®
Press ESP® switch1.
The ABS/ESP
® warning lampv in
the instrument cluster goes out.
You are now again in normal driving
mode with the ESP
® switched on.
Electro-hydraulic brake system
The electro-hydraulic brake system com-
bines a hydraulic brake circuit with elec-
tronically controlled brake servo
assistance. You have increased braking
safety and improved braking comfort.
Warning!G
When the ABS/ESP® warning lampv is
illuminated continuously, the ESP® is
switched off or is not operational due to a
malfunction. Vehicle stability in standard
driving maneuvers reduces.
Adapt your speed and driving to the prevail-
ing road conditions and to the non-operating
status of the ESP
®.
!Avoid spinning of a drive wheel for an ex-
tended period with the ESP® switched off. This
may cause serious damage to the drivetrain
which is not covered by the Mercedes-Benz
Limited Warranty.
Warning!G
Never ignore a brake malfunction indicated
in the speedometer display, for example by
the ; (USA only) or 3 (Canada only)
indicator lamp. Refer to the “Practical hints”
section (
page 303). Also read and ob-
serve the messages in the instrument
cluster multifunction display (
page 329).

87 Safety and Security
Driving safety systems
The electro-hydraulic brake system is
automatically activated when you

unlock the vehicle with the SmartKey

open the driver’s or passenger door

turn the SmartKey in the starter switch
to position1

depress the brake pedal

release the parking brake
Warning!G
The electro-hydraulic brake system requires
electrical power to operate.
A malfunction in the vehicle’s power supply
or electrical system may impair brake sys-
tem operation and switch it into its emer-
gency operation mode. In such a case, the
red brake warning lamp (
page 303)
comes on and warning messages
(
page 329) appear in the multifunction
display while driving. To brake, the driver
must then apply significantly greater brake
pedal pressure and depress the pedal much
further to obtain the expected braking ef-
fect. If necessary, apply full pressure to the
brake pedal. Stopping distance is increased!
If there is a malfunction in the electro-hy-
draulic brake system, we recommend that
the vehicle be transported with all wheels
off the ground using flatbed or appropriate
wheel lift/dolly equipment.
A tow bar must be used if circumstances do
not permit the use of the recommended
towing methods and the vehicle requires
towing with all four wheels on the ground.
Towing the vehicle with all four wheels on
the ground is only permissible for distances
u p t o 3 0 m i l e s ( 5 0 k m ) a n d a t a s p e e d n o t t o
exceed 30 mph (50 km/h). For more infor-
mation, see “Towing the vehicle”
(
page 370).
iIf the electro-hydraulic brake system is acti-
vated as the brake pedal is first depressed, you
may feel a reduced pedal resistance and longer
pedal travel than normal. When releasing the
pedal, you may also feel the brake pedal pulsate
and you may hear a sound which is caused by the
activation of the electro-hydraulic brake system
pump. This is normal and not an indication of a
malfunction. Pedal travel returns to normal when
you release the brake pedal and the sound soon
ceases.
If you experience the above while driving and the
red brake warning lamp (
page 303) illumi-
nates and/or warning messages appear in the
multifunction display (
page 329), the brake
system is malfunctioning. Follow the instructions
of the warning message(s) and have the brake
system checked immediately.

88 Safety and Security
Driving safety systems
The electro-hydraulic brake servo assis-
tance switches off automatically

approximately 2 minutes after you
turned the SmartKey in the starter
switch to position0 or removed the
SmartKey

approximately 20 seconds after you
locked the vehicle from the outside
Notes on driving with the
electro-hydraulic brake system

Following extended periods of only mi-
nor loads to your brake system, you
should occasionally apply the brakes
when traveling at high speeds. This im-
proves the grip of the brake pads and
prevents possible brake noise.

After driving on wet or snow-covered
roads, you should apply your brakes
firmly before parking your vehicle. This
produces heat which serves to dry the
brake disks.

On long and steep grades, shift to a
lower gear (gear range1, 2, or 3) to
prevent the brakes from overheating
and to reduce brake wear.

After hard braking, it is advisable to
drive on for some time so that the air
stream will cool down the brakes
faster.

Only Mercedes-Benz approved compo-
nents (e.g. brake pads) should be
installed on your vehicle. Brake pads
not approved by Mercedes-Benz may
impair the safety of your vehicle.
Warning!G
Have brake pad replacement and other work
on the electro-hydraulic brake system car-
ried out by qualified technicians only. Con-
tact an authorized Mercedes-Benz Center
for further information. The electro-hydrau-
lic brake system must be deactivated prior
to working on the system. High pressure is
intermittently built up in the system as part
of its automatic self-test. In addition, the
system is automatically activated when the
vehicle is unlocked by remote control, when
the driver or passenger door is opened,
when the SmartKey in the starter switch is
turned to position1, when the brake pedal
is depressed or when the parking brake is
released. Failure to deactivate the system
prior to maintenance will cause brake pis-
tons to extend and brake fluid to leak, which
may result in injuries (contusions and acid
burns). Extended brake pistons may also
cause injury.
Warning!G
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.

89 Safety and Security
Performance enhancement system
Performance enhancement system
Airbrake
The Airbrake enhances the vehicle’s driv-
ing stability. It adapts the aerodynamics of
the vehicle to the driving conditions ac-
cording to the speed and the mode set.
This is achieved using a moveable spoiler.
The Airbrake is located at the rear edge of
the trunk lid.
Warning!G
When operating the Airbrake, make sure
there is no danger of anyone being harmed
by the Airbrake operation (i.e. raising and
lowering of flap). Be especially careful when
small children are around.
Warning!G
The following factors increase the risk of
accidents:

Excessive speed, especially in turns

Wet and slippery road surfaces

Following another vehicle too closely
The Airbrake cannot reduce this risk.
Always adjust your driving style to the pre-
vailing road and weather conditions.
iIn winter operation, the maximum effective-
ness of the Airbrake is only achieved with winter
tires (M + S tires) or snow chains as required.

90 Safety and Security
Performance enhancement system
The Airbrake switch is on the upper part of
the center console.
Airbrake modes
1Manual
2Automatic
3Test
4Airbrake switch
Switch on the ignition (page 40).
The system runs a self-test to ensure
correct operation of the Airbrake.Test mode
The test mode allows you to check that the
Airbrake is functioning correctly.
This mode can only be activated when the
vehicle is at standstill.
Slide Airbrake switch4 to
position3.
The Airbrake swivels upwards to an
angle of 60°.
Release the Airbrake switch.
The Airbrake returns to its initial
position.Manual mode
In this mode, the Airbrake is set to an angle
of 30° (Mercedes-Benz SLR McLaren
722 Edition: 35°). The driver downforce
mode enhances stability while reducing
agility.
Slide the Airbrake switch4 to
position1.
The Airbrake swivels upwards to an an-
gle of 30° (Mercedes-Benz SLR
McLaren 722 Edition: 35°) and stays in
this position.
iIn manual mode, the Airbrake automatic
function is activated during hard braking, see
“Automatic mode” (
page 91).
!Before deactivating manual mode, check
the Airbrake for any objects which may have be-
come lodged, e.g. branches or leaves, and
remove them.
Otherwise the Airbrake can no longer function
correctly.