69 Safety and Security
Driving safety systems
After a hard collision or damage to the
front of the vehicle from an accident, have
the adjustment and operation of the radar
sensors checked by an authorized
Mercedes-Benz Center.
If BAS Plus is not available due to a radar
sensor malfunction, the braking system
will continue to function normally with full
brake boost and full standard BAS
function.EBP
The Electronic Brake Proportioning (EBP)
enhances braking effectiveness by allow-
ing the rear brakes to supply a greater pro-
portion of the braking effort in straight line
braking without a loss of vehicle stability.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 spin-
ning or if the vehicle starts to skid. By ap-
plying 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 ESP
® warning lamp v in the instru-
ment cluster flashes when the ESP® is en-
gaged.
The ESP
® warning lamp v in the instru-
ment cluster comes on when you switch on
the ignition (
page 336). It goes out when
the engine is running.
Warning!G
When the EBP is malfunctioning, the ABS,
BAS, BAS Plus* and ESP® are also switched
off.
If the EBP is malfunctioning, the brake sys-
tem will still function with full brake boost.
However, the rear wheels could lock up dur-
ing emergency braking situations, for exam-
ple. You could lose control of the vehicle and
cause an accident. Adapt your driving style
to the changed driving characteristics.
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70 Safety and Security
Driving safety systems
For more information, see “Practical hints”
section (
page 572) and (page 580).
Warning!G
Never switch off the ESP® when you see the
ESP® warning lamp v flashing in the in-
strument cluster. In this case proceed as fol-
lows:
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 result-
ing 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.
iDISTRONIC Plus* and cruise control are
switched off when the ESP® engages.
iThe ESP® will only function properly if you
use wheels of the recommended tire size
(
page 678).
!Because the ESP® operates automatically,
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 electronic parking brake is being tested
on a brake test dynamometer
the vehicle is being towed with the
front/rear axle raised
Active braking action through the ESP
® may oth-
erwise seriously damage the brake system.
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71 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
you cannot activate the cruise control
or the DISTRONIC Plus*
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 stan-
dard driving maneuvers.
Warning!G
Switch on the ESP® immediately if the afore-
mentioned circumstances do not apply any-
more. Otherwise the ESP
® will not stabilize
the vehicle when it is starting to skid or a
wheel is spinning.
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72 Safety and Security
Driving safety systems
1ESP® off/on
Press ESP® switch1 until the ESP®
warning lampv in the instrument
cluster comes on.
The ESP
® is switched off.Switching on the ESP
®
Press ESP® switch1.
The ESP
® warning lampv in the in-
strument cluster goes out.
You are now again in normal driving
mode with the ESP
® switched on.
iWhen the ESP® is switched off and one or
more drive wheels are spinning, the ESP® warn-
ing lampv in the instrument cluster flashes.
However, the ESP
® will then not stabilize the
vehicle.
Warning!G
When the ESP® warning lampv is illumi-
nated 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.
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73 Safety and Security
Driving safety systems
PRE-SAFE® Brake* (vehicles with
DISTRONIC Plus* only)
PRE-SAFE
® Brake* can assist you in mini-
mizing the risk of a rear-end collision with
a vehicle in front of you and in reducing the
severity of an accident. At speeds over ap-
proximately 20 mph (30 km/h), it will
warn you of a possible collision
automatically begin to brake the vehi-
cle lightly in a speed range of up to
112 mph (180 km/h)
activate preventative occupant safety
measures (PRE-SAFE®) (page 56)PRE-SAFE
® Brake will only assist you by
automatically initiating braking if the driver
and front passenger have their seat belts
fastened.
Using the radar sensors, PRE-SAFE
® Brake
detects obstacles that are in your driving
path for a sufficient period of time for the
system to recognize it. If you approach a
vehicle and PRE-SAFE
® Brake has estab-
lished that the distance to the vehicle
ahead at your current speed is so close
that PRE-SAFE
® Brake will not be capable
of slowing the vehicle sufficiently, the sys-
tem will initially warn you visually and
acoustically.
When travelling in Canada in a vehicle not
registered in Canada, you must switch off
the radar sensor system* (
page 272). Canadian law does not permit the use of
the radar sensor system* (
page 272) for
vehicles from outside of Canada. When you
switch off the radar sensor system*, the
following functions are deactivated:
BAS Plus* (page 67)
DISTRONIC Plus* (page 411)
Park Assist* (page 435)
PRE-SAFE® Brake
Warning!G
PRE-SAFE® Brake is a convenience system
designed to assist the driver during vehicle
operation. The responsibility for the vehicle
speed and the distance to the vehicle ahead,
including most importantly brake operation
to assure safe stopping distance, always re-
mains with the driver.
Always pay attention to traffic conditions
even while PRE-SAFE® Brake is switched on.
Otherwise, you may not be able to recognize
dangerous situations until it is too late and
could cause an accident resulting in person-
al or fatal injury to you or others.
iUSA only:
This device has been approved by the FCC as a
“Vehicular Radar System”. The radar sensor is
intended for use in an automotive radar system
only. Removal, tampering, or altering of the de-
vice will void any warranties, and is not permitted
by the FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
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74 Safety and Security
Driving safety systems
When the distance to the forward vehicle is
too small, the distance warning lampl
comes on in the instrument cluster. If you
approach the forward vehicle very quickly,
you will hear a warning tone.
If you do not apply the brakes yourself or
maneuver around a sensed obstacle, the
vehicle will automatically initiate light
braking. PRE-SAFE
® (page 56) is activat-
ed when the distance to the vehicle ahead
at your current speed is so close that
PRE-SAFE
® Brake will not be capable of
slowing the vehicle sufficiently.
iCanada only:
This device complies with RSS-210 of Industry
Canada. Operation is subject to the following
two conditions:
(1) This device may not cause interference, and
(2) this device must accept any interference re-
ceived, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the device will
void any warranties, and is not permitted. Do not
tamper with, alter, or use in any non-approved
way.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.Warning!G
PRE-SAFE® Brake will only respond with
brake assistance if it has clearly detected an
object. Detection can be impeded by
dirty or covered sensors
snowfall or heavy rain
disturbance from other radar sources
strong radar reflection such as in park-
ing garages
PRE-SAFE
® Brake uses radar signals that
are not reflected well by narrow objects and
absorptive materials. For this reason BAS
Plus will not react to
persons and animals
approaching traffic or cross-traffic
PRE-SAFE
® Brake may not detect narrow ve-
hicles driving in front of you, such as motor-
cycles and vehicles driving offset from your
vehicle center.
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77 Safety and Security
Anti-theft systems
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
Activating
With the SmartKey: Remove the
SmartKey from the starter switch.
With the KEYLESS-GO*: Turn off the
engine (
page 337) and open the driv-
er’s door.
Deactivating
Switch on the ignition (page 336).
Anti-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 activating
element (a door, for example) is immedi-
ately closed.
The alarm system will also be triggered
when
the vehicle is raised (only vehicles with
tow-away alarm)
the vehicle is opened with the
mechanical key
a door is opened from the inside
To cancel the alarm after it has been trig-
gered, see “Canceling the alarm”
(
page 78).1Indicator lamp
Arming: Lock your vehicle with the
SmartKey or KEYLESS-GO*.
The turn signal lamps flash three times
to indicate that the vehicle is locked.
The indicator lamp1 flashes to indi-
cate that the alarm system is armed.
iStarting the engine will also deactivate the
immobilizer.
In case the engine cannot be started (yet the ve-
hicle’s battery is charged), the system is not op-
erational. Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in the
USA), or 1-800-387-0100 (in Canada).
iIf the alarm stays on for more than
30 seconds, a call to the Response Center is ini-
tiated automatically by the Tele Aid system
(
page 482) provided Tele Aid service was sub-
scribed to and properly activated, and that nec-
essary mobile phone, power supply and GPS
coverage are available.
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78 Safety and Security
Anti-theft systems
Disarming: Unlock your vehicle with
the SmartKey or KEYLESS-GO*.
The turn signal lamps flash once to in-
dicate that the alarm system is dis-
armed.
Tow-away alarm
Depending on production date, your vehi-
cle may not be equipped with the 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.To cancel the alarm after it has been trig-
gered, see “Canceling the alarm”
(
page 78).
Arming: Lock your vehicle with the
SmartKey or KEYLESS-GO*.
The tow-away alarm is automatically
armed after about 30 seconds.
Disarming: Unlock your vehicle with
the SmartKey or KEYLESS-GO*.
To prevent triggering the tow-away alarm
feature, switch off the tow-away alarm be-
fore towing the vehicle, or when parking ona surface subject to movement, such as a
ferry or auto train.
To switch off the tow-away alarm, see
“Switching the tow-away alarm on/off”
(
page 243).
Canceling the alarm
To cancel the alarm, do one of the follow-
ing:
Insert the SmartKey or SmartKey with
KEYLESS-GO* in the starter switch.
Press the Œ or ‹ button on the
SmartKey or SmartKey with
KEYLESS-GO*.
In vehicles with KEYLESS-GO*:
Grasp an outside door handle.
The SmartKey with KEYLESS-GO must
be within 3 ft (1 m) of the vehicle.
Press the KEYLESS-GO start/stop but-
ton (
page 337).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
iIf the turn signal lamps does not flash three
times one of the following elements may not be
properly closed:
a door
the trunk
Close the respective element and lock the vehi-
cle again.
iThe alarm system will rearm automatically
again after approximately 40 seconds if no door
was opened.
iIf the alarm stays on for more than
30 seconds, a call to the Response Center is ini-
tiated automatically by the Tele Aid system
(
page 482) provided Tele Aid service was sub-
scribed to and properly activated and that neces-
sary mobile phone, power supply and GPS
coverage are available.
iWhen you unlock your vehicle, the tow-away
protection disarms automatically.
The tow-away alarm remains disarmed until you
lock your vehicle again.
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