84 Safety and SecurityDriving safety systemsIn this section you will find information on
the following driving safety systems:
ABS (A
ntilock B
rake S
ystem)
BAS (B
rake A
ssist S
ystem)
ESP
® (E
lectronic S
tability P
rogram)
Electro-hydraulic brake system
ABS
The Antilock Brake System (ABS) regulates
the brake pressure so that the wheels do
not lock during braking. This allows you to
maintain the ability to steer your vehicle.
The ABS is functional above a speed of
approximately 5 mph (8 km/h) indepen-
dent of road surface conditions.
On slippery road surfaces, the ABS will
respond even with light brake pressure.
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 ABS, BAS, ESP
® and electro-hydraulic
brake system cannot reduce this risk.
Always adjust your driving style to the pre-
vailing road and weather conditions.
iIn winter operation, the maximum
effectiveness of the ABS, the BAS, the
ESP
® and electro-hydraulic brake sys-
tem is only achieved with winter tires
(
page 336) or snow chains as re-
quired.
Warning!
G
Do not pump the brake pedal. Use firm,
steady brake pedal pressure instead. Pump-
ing the brake pedal defeats the purpose of
the ABS and significantly reduces braking
effectiveness.
85 Safety and Security
Driving safety systems
The -malfunction warning lamp in the
instrument cluster comes on when you
switch on the ignition. It goes out when the
engine is running.
Braking
If the ABS activates during braking, the
ABS/ESP
® warning lampv in the in-
strument cluster dial flashes. Because of
the electro-hydraulic brake system, you
will not feel any pulsation in the brake ped-
al.
Keep firm and steady pressure on the
brake pedal.
Continuous, steady brake pedal pressure
yields the advantages provided by the ABS,
namely braking power and the ability to
steer the vehicle.The ABS/ESP
® warning lampv flashes
whenever the ABS is activated which can
be an indication of hazardous road condi-
tions and functions as a reminder to take
extra care while driving.
Emergency brake maneuver
Keep continuous full pressure on the
brake pedal.
For more information, see the “Practical
hints” section (
page 353).
Warning!
G
When the ABS is malfunctioning, the BAS
and the ESP
® are also switched off.
When the ABS is malfunctioning, the wheels
may lock during hard braking, reducing
steering capability and extending the brak-
ing distance.
Warning!
G
The ABS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking or steering efficiency
beyond that afforded by the condition of the
vehicle brakes and tires or the traction af-
forded. The ABS cannot prevent accidents,
including those resulting from excessive
speed in turns, following another vehicle too
closely, or hydroplaning. Only a safe, atten-
tive, and skillful driver can prevent acci-
dents. The capabilities of an ABS equipped
vehicle must never be exploited in a reck-
less or dangerous manner which could jeop-
ardize the user’s safety or the safety of
others.
86 Safety and SecurityDriving safety systemsBAS
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
®)
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 spin-
ning or if the vehicle starts to skid. By ap-
plying brakes to the appropriate wheel and
by limiting engine output, the ESP
® works
to stabilize the vehicle. The ESP
® is espe-
cially useful while driving off and on wet or
slippery road surfaces.
The ABS/ESP
® warning lampv in the
instrument cluster flashes when the ESP
®
is engaged.
The ABS/ESP
® warning lampv in the
instrument 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
The BAS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking efficiency beyond that
afforded 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, fol-
lowing another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful
driver can prevent accidents. The capabili-
ties 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.
88 Safety and SecurityDriving safety systemsSwitching off the ESP
®
To improve the vehicle’s traction, turn off
the ESP
® in driving situations where it
would be advantageous to have 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 traction control will still brake a
spinning wheel
the ESP
® continues to operate when
you are braking
you cannot activate Distronic*The switch is located on the center con-
sole.
1ESP
® switch
Press ESP
® switch1 until the
ABS/ESP®warning lampv in the
instrument cluster comes on.
The ESP
® is deactivated.
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 driving
maneuvers.
Do not switch off the ESP
® when a Minis-
pare or collapsible tire is mounted.
!Turn on the ESP
® immediately if the
aforementioned circumstances do not
apply anymore.
iWhen the ESP
® is switched off and one
or more drive wheels are spinning, the
ABS/ESP
® warning lampv in the
speedometer flashes. However, the
ESP
® will then not stabilize the vehicle.
89 Safety and Security
Driving safety systems
Switching on the ESP
®
Press ESP
® button1.
The ABS/ESP® warning lampv in
the instrument cluster goes out.
You are now again in normal driving
mode with 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.
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
extended 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)
warning lamp. Refer to the “Practical hints”
section (
page 354). Also read and ob-
serve the messages in the multifunction dis-
play (
page 363).
90 Safety and SecurityDriving safety systems
The electro-hydraulic brake system is auto-
matically activated when you
unlock the vehicle with the SmartKey
or the KEYLESS-GO*
open the driver’s or passenger door
turn the SmartKey in the starter switch
to position1
in vehicles with KEYLESS-GO*, press
the start/stop button on the gear
selector lever once
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 354) and
warning messages in the instrument cluster
(
page 363) come on while driving. To
brake, the driver must then apply signifi-
cantly greater brake pedal pressure and
depress the pedal much further to obtain
the expected braking effect. If necessary,
apply full pressure to the brake pedal.
Brakes may only be applied to the front
wheels. Stopping distance is increased!
If there is a malfunction in the
electro-hydraulic brake system, we recom-
mend that the vehicle be transported with
all wheels off the ground using flatbed or ap-
propriate 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
up to 30 miles (50 km) and at a speed not to
exceed 30 mph (50 km/h). For more infor-
mation, refer to “Towing the vehicle”
(page 437).
91 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 2 minutes after you
pressed the KEYLESS-GO* start/stop
button to turn off the engine or power
supply and opened the driver’s door
(with driver’s door open, the starter
switch is set to position0, same as
SmartKey removed from starter
switch)
approximately 20 seconds after you
locked the vehicle from outside
iIf the electro-hydraulic brake system is
activated as the brake pedal is first de-
pressed, 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 driv-
ing and the red brake warning lamp
(page 354) illuminates and/or warn-
ing messages appear in the instrument
cluster (
page 363), the brake system
is malfunctioning. Follow the instruc-
tions of the warning message(s) and
have the brake system checked imme-
diately.
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 SmartKey, when the
driver or passenger door is opened, when
the starter switch is turned to position1,
when the brake pedal is depressed or when
the parking brake is released. Failure to de-
activate the system prior to maintenance
will cause brake pistons to extend and brake
fluid to leak, which may result in injuries
(contusions and acid burns). Extended
brake pistons may also cause injury.
92 Safety and SecurityDriving safety systemsNote on driving with the
electro-hydraulic brake system
Following extended periods of only
minor loads to your brake system, you
should occasionally apply the brakes
when traveling at high speeds. This
improves the grip of the brake pads.
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 and help prevent corro-
sion.
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 fast-
er.
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
Be very careful not to endanger other road
users when you apply the brakes.