76 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 especially
useful while driving off and on wet or slip-
pery road surfaces.
The ABS/ESP warning lamp v in the
instrument cluster flashes when the ESP is
engaged.
The ABS/ESP warning lamp v in the
instrument cluster comes on when you
turn the SmartKey in the starter switch to
position2 or press the KEYLESS-GO*
start/stop button twice. It goes out when
the engine is running.
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.
77 Safety and Security
Driving safety systems
More information can be found in the
“Practical hints” section (
page 311).
Warning!
G
Never switch off the ESP when you see the
ABS/ESP warning lamp v fl as h in g i n t he
instrument cluster. In this case proceed as
follows:
While driving off, apply as little throttle
as possible.
While driving, ease up on the accelera-
tor.
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 us-
er’s safety or the safety of others.!The ESP will only function properly if
you use wheels of the recommended
tire size (
page 394).
!Vehicles without 4MATIC:
Because of the ESP’s automatic opera-
tion, the engine and ignition must be
shut off (SmartKey in starter switch
position0 or1 or KEYLESS-GO
start/stop button* in position0 or1)
when:
the parking brake is being tested on
a brake test dynamometer
the vehicle is being towed with the
front axle raised
Active braking action through the ESP
may otherwise seriously damage the
brake system.
For information on vehicles with
4MATIC, see “Four wheel electronic
traction system (4MATIC) with the
ESP” (
page 82).
80 Safety and SecurityDriving safety systems
The SBC brake system is automatically ac-
tivated 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 gear selector
lever once
depress the brake pedal
release the parking brake
If there is a malfunction in the SBC 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 cir-
cumstances do not permit the use of the
recommended towing methods and the ve-
hicle 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 information, refer to “Towing the vehi-
cle” (
page 381).
iIf the SBC brake system is activated 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 SBC brake system-
pump. This is normal and not an indica-
tion of a malfunction. Pedal travel
returns to normal when you release the
brake pedal and the sound soon ceas-
es.
If you experience the above while driv-
ing and the red brake warning lamp
(page 312) illuminates and/or warn-
ing messages appear in the instrument
cluster (
page 318), the brake system
is malfunctioning. Follow the instruc-
tions of the warning message(s) and
have the brake system checked imme-
diately.
81 Safety and Security
Driving safety systems
The SBC brake servo assistance switches
off automatically
approximately two minutes after you
turned the SmartKey in the starter
switch to position0 or removed the
SmartKey
approximately two 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 position 0, same as
SmartKey removed from starter
switch)
approximately 20 seconds after you
locked the vehicle from outside
Note on driving with the SBC
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.
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 in-
stalled on your vehicle. Brake pads not
approved by Mercedes-Benz may im-
pair the safety of your vehicle.
Warning!
G
Have brake pad replacement and other work
on the SBC brake system carried out by
qualified technicians only. Contact your
Mercedes-Benz Center for further informa-
tion. The SBC brake system must be deacti-
vated prior to working on the system. High
pressure is intermittently built up in the sys-
tem as part of its automatic self-test. In ad-
dition, 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
position
1, when the brake pedal is de-
pressed or when the parking brake is re-
leased. 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
Be very careful not to endanger other road
users when you apply the brakes.
82 Safety and SecurityDriving safety systemsFour wheel electronic traction system (4MATIC) with the ESP
Models with all-wheel-drive only.
The 4MATIC improves vehicle’s ability to
use available traction, e.g. during winter
operation in mountains under snowy
conditions, by applying power to all four
wheels.
Warning!
G
If you see the ESP warning lampv flash-
ing in the speedometer, proceed as follows:
While driving off, apply as little throttle
as possible
While driving, ease up on the accelera-
tor
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.!Do not tow with one axle raised.
Otherwise the transfer case can be
damaged, which is not covered by the
Mercedes-Benz Limited Warranty.
!Performance testing must only be con-
ducted on a two-axle dynamometer.
Otherwise the transfer case can be
damaged, which is not covered by the
Mercedes-Benz Limited Warranty.!Because of the ESP’s automatic opera-
tion, the engine and ignition must be
shut off (SmartKey in starter switch
position0 or1 or KEYLESS-GO
start/stop button* in position0 or1)
when the parking brake is being tested
on a brake test dynamometer.
Active braking action through ESP may
otherwise seriously damage the front
or rear axle brake system.
Operational tests with the engine
running can only be conducted on a
two-axle dynamometer.
83 Safety and Security
Anti-theft systems
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
Activating
With the SmartKey: Removing the
SmartKey from the starter switch acti-
vates the immobilizer.
With KEYLESS-GO*: Turning off the en-
gine by means of the KEYLESS-GO
start/stop button on the gear selector
lever activates the immobilizer.Deactivating
With the SmartKey: Inserting the
SmartKey in the starter switch deacti-
vates the immobilizer.
With KEYLESS-GO*: Starting the en-
gine by means of the start/stop button
on the gear selector lever deactivates
the immobilizer.
iIn case the engine cannot be started
(yet the vehicle’s battery is charged),
the system is not operational. Contact
an authorized Mercedes-Benz Center
or call 1-800-FOR-MERCedes (in the
USA), or 1-800-387-0100 (in Canada).
84 Safety and SecurityAnti-theft systemsAnti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens
a door
the trunk
the hood.
The alarm will stay on, even if the activat-
ing element (a door, for example) is imme-
diately closed.
The alarm system will also be triggered
when
someone attempts to raise the vehicle.Arming the alarm system
The alarm system is armed within approxi-
mately ten seconds after locking the vehi-
cle with the SmartKey or KEYLESS-GO*.
The turn signal lamps flash three times to
indicate that the alarm system is activated.
The indicator lamp in the central locking
switch (
page 25) begins to flash after
arming the alarm system.Disarming the alarm system
The alarm system is disarmed when you
unlock your vehicle with the SmartKey or
KEYLESS-GO*. The turn signal lamps flash
once to indicate that the alarm system is
deactivated.
iIf the alarm stays on for more than
20 seconds, an emergency call is initi-
ated automatically by the Tele Aid sys-
tem* (
page 250) provided Tele Aid
service was subscribed to and properly
activated, and that necessary cellular
service and GPS coverage are avail-
able.
iIf the turn signal lamps do not flash
three times one of the following ele-
ments may not be properly closed:
a door
the trunk lid
Close the respective element and lock
the vehicle again.
85 Safety and Security
Anti-theft systems
Canceling the alarm
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press the Œ or ‹ button on the
SmartKey.
The alarm is canceled.
With KEYLESS-GO*
Grasp the outside door handle.
or
Press the KEYLESS-GO* start/stop
button.
The alarm is canceled.
Tow-away alarm
Once the tow-away alarm is armed, a visual
and audible alarm will be triggered when
someone attempts to raise the vehicle.Arming the tow-away alarm
When you lock your vehicle, the tow-away
alarm is automatically armed after about
30 seconds.
When you unlock your vehicle, the
tow-away protection disarms automatical-
ly.
Disarming the tow-away alarm
To prevent triggering the tow-away alarm
feature, switch off the tow-away alarm be-
fore towing the vehicle, or when parking on
a surface subject to movement, such as a
ferry or auto train.
The button is located on the overhead con-
trol panel.
iThe tow-away protection alarm is trig-
gered, for example, if the vehicle is lift-
ed on one side.
If the alarm stays on for more than
20 seconds, an emergency call is initi-
ated automatically by the Tele Aid sys-
tem* (
page 250), provided that the
Tele Aid service was subscribed to and
properly activated, and that necessary
cellular service and GPS coverage are
available.