
The ETDs for the rear outer seats will activate
with or without the respective seat belts
fastened.
In an impact, the ETDs remove slack from the
seat belts in such a way that the seat belts fit
more snugly against the body. Seat belt force
limiters, when activated, are employed to
help reduce the peak force exerted by the
seat belts on occupants during a crash.
i The ETDs do not correct an incorrect seat
position or incorrectly worn seat belts.
The ETDs do not pull occupants back
toward the seat backrest.GWarning!
Pyrotechnic ETDs that were activated must be
replaced.
For your safety, when disposing of the
pyrotechnic ETDs always follow our safety
instructions. These are available at any
authorized Mercedes-Benz Center.
The PRE-SAFE ®
system has electrically
operated reversible pre-tensioners that do
not require replacement after activation.
Automatic comfort-fit feature seat belt
An automatic comfort-fit feature for the front
seats reduces the retracting force of the seat
belts when they are in normal use.
Preventive occupant safety (PRE-
SAFE ®
)
GWarning!
The PRE-SAFE ®
system is intended to reduce
the effects of an accident on vehicle
occupants who are wearing their seat belt
properly. Despite your vehicle being equipped
with the PRE-SAFE ®
system, the possibility of
personal injuries occurring as a result of an
accident cannot be eliminated. Therefore,
always drive carefully and adjust your driving
to the prevailing road, weather, and traffic
conditions.
The PRE-SAFE ®
system takes preventive
measures to better protect the occupants
from the possibility of personal injuries in the
following hazardous situations:
R emergency braking situations, e.g. if the
Brake Assist System (BAS) ( Y page 63) is
activated
or when
vehicles with DISTRONIC PLUS:
the BAS PLUS ( Y page 63) or the PRE-
SAFE ®
Brake ( Y page 69) is strongly
engaging
R when the radar sensors recognize the
immediate risk of collision in certain
situations (vehicles with DISTRONIC PLUS)
R critical dynamic driving situations, e.g.
when the vehicle has been caused to
understeer or oversteer because it has
exceeded its physical limitations or in case
of evasive steering maneuvers at speeds
above approximately 85 mph (140 km/h)
The PRE-SAFE ®
system takes the following
measures when it is activated:
R The front seat belts are pre-tensioned
automatically.
R If the front passenger seat is in an
unfavorable position, the seat will be
adjusted to a position that seeks to better
protect the occupant.
R The system increases the air pressure in
the air pockets (on the sides of the seat
cushion and backrest) of the drive-dynamic
multicontour front seats.
R If the vehicle is in a critical dynamic driving
situation, the door windows and the tilt/
sliding sunroof or panorama roof with tilt/
sliding panel also closes, except for a
minimal gap that remains open.
If the closing procedure of any of these
elements is blocked, it will stop and open
slightly.
Once the hazardous situation no longer exists
and an accident has been avoided, the PRE-
SAFE ®
system loosens the seat belt pre-Occupant safety53Safety and security212_AKB; 2; 41, en-USd2ureepe,Version: 2.11.8.12009-07-17T09:14:21+02:00 - Seite 53Z

tension and decreases the air pressure in the
air pockets of the drive-dynamic multicontour
front seats. All of the PRE-SAFE ®
system
settings can be re-adjusted following the
critical driving event.
If the seat belts do not release:XAdjust the seat backrest or seat slightly to
the rear until the seat belt tension is
reduced.
The locking mechanism releases.
! When moving the seats, make sure there
are no items in the footwell or behind the
seats. Otherwise, you could damage the
seats and/or the items.
For information on the seat belt adjustment
function as an integrated comfort feature of
the PRE-SAFE ®
system, see ( Y page 51).
NECK-PRO active front head
restraints
The NECK-PRO active front head restraints
are intended to offer the driver and front
passenger increased protection from
whiplash-type injuries. In the event of a rear-
end collision, the NECK-PRO active front head
restraints are designed to move forward and
up in the direction of travel. They thus provide
the head with increased support earlier on in
the collision sequence. The NECK-PRO active
front head restraints will move forward and
up whether the seats are occupied or not.
GWarning!
Do not attach any objects (e.g. hangers) to the
head restraint posts. Otherwise, the NECK-
PRO active front head restraints may not be
able to function properly or offer the intended
degree of protection they were designed for
in the event of a rear-end collision.
GWarning!
Only use seat or head restraint covers which
have been tested and approved by Mercedes-
Benz for your vehicle model.
Using other seat or head restraint covers may
interfere with or prevent the activation of the
NECK-PRO active front head restraints and/
or the deployment of the front side impact air
bags or pelvis air bags.
Contact an authorized Mercedes-Benz Center
for availability.
When the NECK-PRO active front head
restraints have been triggered in an accident,
the NECK-PRO active front head restraints
must be reset. Otherwise, the NECK-PRO
active front head restraints cannot offer any
additional protection in the event of another
rear-end collision.
For information on resetting the activated
NECK-PRO active front head restraints, see
“Resetting activated head restraints”
( Y page 316).
You cannot remove the NECK-PRO active
front head restraints.GWarning!
For your protection, drive only with properly
positioned head restraints.
Adjust the head restraint so that it is as close
to the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
injury to the head and neck in the event of an
accident or similar situation.
For information on head restraint adjustment,
see “Head restraint height” ( Y page 89), or
see “Head restraint fore and aft adjustment”
( Y page 89).
Correct driver seat adjustment
GWarning!
In order to avoid possible loss of vehicle
control the following must be done before the
vehicle is put into motion:
R seat adjustment
R head restraint adjustment
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RA child in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to
completely eliminate this risk is to never
place a child in a rear-facing child restraint
in the front seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint in a backseat.
R If you must install a rear-facing child
restraint on the front passenger seat
because circumstances require you to do
so, make sure the 45 indicator lamp
is illuminated, indicating that the front
passenger front air bag is deactivated.
Should the 45 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check the 45 indicator
lamp while driving to make sure the
45 indicator lamp is illuminated. If
the 45 indicator lamp goes out or
remains out, do not transport a child on the
front passenger seat until the system has
been repaired.
A child in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates.
R If you have to place a child in a forward-
facing child restraint on the front passenger
seat, move the seat as far back as possible,
use the proper child restraint
recommended for the age, size and weight
of the child, and secure child restraint with
the vehicle’s seat belt according to the child
seat manufacturer’s instructions.GWarning!
Infants and small children should never share
a seat belt with another occupant. During an
accident, they could be crushed between the
occupant and seat belt.
A child’s risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.
Children too big for a toddler restraint must
ride in seats using regular seat belts. Position
shoulder belt across chest and shoulder, not
face or neck. A booster seat may be
necessary to achieve proper seat belt
positioning for children over 41 lb (18 kg) until
they reach a height where a lap/shoulder belt
fits properly without a booster.
When the child restraint is not in use, remove
it from the vehicle or secure it with the seat
belt to prevent the child restraint from
becoming a projectile in the event of an
accident.
Installation of infant and child restraint
systemsGObserve Safety notes, see page 56.GWarning!
Always lock the seat backrests in their upright
position when the rear seats are occupied by
passengers. Lock the seat backrests in their
upright position before installing top tether
straps or when the extended cargo
compartment is not in use. Make sure that
seat backrests are secured properly by
pushing and pulling on the seat backrests. If
a seat backrest is not locked properly, the
seat backrest could fold. The child seat would
no longer be supported properly or positioned
to provide its intended benefit. That could
cause serious or even fatal injuries.
This vehicle is equipped with tether
anchorages for a top tether strap at each of
the rear seating positions.
Top tether straps enable an additional
connection to be made between child
restraint systems secured with LATCH-type
(ISOFIX) anchors and rear seats. This can
further reduce the risk of injury.
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The LATCH-type (ISOFIX) anchors are
blended with covers.
Information sign : on the cover indicates the
position of anchor ;.
XInstall a LATCH-type (ISOFIX) child seat
according to the manufacturer’s
instructions.
The anchorage ring covers of anchors ;
swings back with insert the mounting
fittings of a LATCH-type (ISOFIX) child seat.
A rigid connection between the child seat
and the body of the vehicle is established.
XMake sure that the seat belt for the rear
center seat can operate freely with a child
seat installed.
Child safety
Child safety locks
GObserve Safety notes, see page 56.GWarning!
Children could open a rear door from the
inside. This may cause serious personal injury
or an accident. Therefore, secure the rear
doors with the child safety locks whenever
children are riding in the back seats of the
vehicle.
The child safety locks on the rear doors
enable you to secure each rear door
individually. You cannot open a secured rear
door from the inside. You can open the rear
door from the outside when the vehicle is
unlocked.
XSecuring: Press the lever up in direction of
arrow :.
XCheck to make sure the child safety locks
are working properly.
XReleasing: Press the lever down in
direction of arrow ;.
Override switch
GObserve Safety notes, see page 56.
With the override switch you can disable the
rear door window switches in the rear door
panels. This can be useful, for instance, when
you have children riding in the rear passenger
compartment.
GWarning!
Activate the override switch when children
are riding in the back seats of the vehicle. The
children may otherwise injure themselves,
e.g. by becoming trapped in the rear door
window opening.
XActivating: Press override switch :.
Indicator lamp ; comes on.
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The rear door windows can no longer be
operated using the respective switch
located in the rear doors.
You can still operate the rear door windows
using the switches located on the door
control panel of the driver’s door.
XDeactivating: Press override switch :
again.
Indicator lamp ; goes out.
The rear door windows can be operated
again using the respective switch located
in the rear doors.
For more information on power windows, see
the “Controls in detail” section
(Y page 105).
Panic alarm
XActivating: Press and hold !
button : for at least 1 second.
An audible alarm and flashing exterior
lamps will operate.
XDeactivating: Press ! button : again.
or
XInsert the SmartKey into the starter switch.
or
XPress the KEYLESS-GO start/stop button.
The SmartKey with KEYLESS-GO must be
inside the vehicle.
iUSA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any
interference received, including
interference that may cause undesired
operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
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 received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Driving safety systems
Introduction
This section contains information about the
following driving safety systems:
RABS (Antilock Brake System)
RAdaptive Brake
RBAS (Brake Assist System)
RBAS PLUS (Brake Assist System PLUS)
REBP (Electronic Brake Proportioning)
RESC (Electronic Stability Control)
RPRE-SAFE® Brake (Preventive Occupant
Safety System Brake)
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iIn winter operation, the maximum
effectiveness of most of the driving
systems described in this section is only
achieved with winter tires, or snow chains
as required.
Safety notesGWarning!
The following factors increase the risk of
accidents:
R Excessive speed, especially in turns
R Wet and slippery road surfaces
R Following another vehicle too closely
The driving safety systems described in this
section cannot reduce these risks or prevent
the natural laws of physics from acting on the
vehicle. They cannot increase braking or
steering efficiency beyond that afforded by
the condition of the vehicle brakes and tires
or the traction afforded.
Only a safe, attentive, and skillful driver can
prevent accidents.
The capabilities of a vehicle equipped with the
driving safety systems described in this
section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user’s safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear.
ABSGObserve Safety notes, see page 62.GWarning!
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal defeats the purpose of the ABS
and significantly reduces braking
effectiveness.
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) independent
of road surface conditions.
On slippery road surfaces, the ABS will
respond even to light brake pressure.
The ABS indicator lamp ! in the
instrument cluster comes on when you switch
on the ignition. It goes out when the engine
is running.
Braking
At the instant one of the wheels is about to
lock up, a slight pulsation can be felt in the
brake pedal. The pulsation indicates that the
ABS is in the regulating mode.
XKeep firm and steady pressure on the brake
pedal while you feel the pulsation.
Continuous, steady brake pedal pressure
yields the advantages provided by the ABS,
namely braking power and the ability to steer
the vehicle.
The pulsating brake pedal can be an
indication of hazardous road conditions and
functions as a reminder to take extra care
while driving.
Emergency brake maneuver
XKeep continuous full pressure on the brake
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GWarning!
If the ABS malfunctions, other driving safety
systems such as the BAS or the ESC are also
switched off. Observe indicator and warning
lamps that may come on as well as messages
in the multifunction display that may appear.
If the ABS malfunctions, the wheels may lock
during hard braking, reducing steering
capability and extending the braking distance.
BAS
GObserve Safety notes, see page 62.
The Brake Assist System (BAS) operates in
emergency situations. If you apply the brakes
very quickly, the BAS provides full brake
boost automatically, thereby potentially
reducing the braking distance.
XApply 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.
GWarning!
If the BAS malfunctions, the brake system still
functions, but without the additional brake
boost available that the BAS would normally
provide in an emergency braking maneuver.
Therefore, the braking distance may increase.
BAS PLUS
The Brake Assist System PLUS (BAS PLUS)
operates in emergency braking situations and
uses radar sensors to assess the traffic
situation. BAS PLUS assists you in braking at
speeds above approximately 20 mph
(30 km/h).
When traveling in Canada in a vehicle not
registered in Canada, you must switch off the
radar sensor system ( Y page 144). Canadian
law does not permit the use of the radar
sensor system for vehicles from outside of
Canada.
When you switch off the radar system, the
following functions are deactivated:
R BAS PLUS
R PRE-SAFE ®
Brake ( Y page 69)
R DISTRONIC PLUS ( Y page 149)GWarning!
BAS PLUS 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 remains with
the driver.
Always pay attention to traffic conditions
even while BAS PLUS is switched on.
Otherwise, you may not be able to recognize
dangerous situations until it is too late and
could cause an accident. Personal or fatal
injury to you or others may be the result.
i 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 device 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.
BAS PLUS detects obstacles that are in your
driving path for a sufficient period of time to
permit the system to recognize these
obstacles. If you approach the detected
obstacle quickly, BAS PLUS calculates the
level of brake power boost appropriate for the
circumstance to supply when the driver
applies the brakes.
When you step quickly on the brake pedal in
an emergency braking situation, BAS PLUS
automatically regulates the brake power
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boost to a level that is suitable for the traffic
situation.
If BAS PLUS requires a particularly high brake
power boost, PRE-SAFE ®
is activated at the
same time.XKeep constant pressure on the brake pedal
until the emergency braking situation is
over.
During this process, the ABS prevents the
wheels from locking up.
The brakes will resume normal operation
after
R the brake pedal is released
R no obstacles are detected in your path
R the system no longer senses a risk of a
collision
BAS PLUS is then deactivated.
BAS PLUS can react to stationary obstacles
such as standing or parked vehicles at road
speeds of up to approximately 40 mph
(70 km/h).
BAS PLUS can only assist you when the radar
sensors are switched on and functional. You
can check whether the sensors are active by
switching on DISTRONIC PLUS
( Y page 149) or using the Radar sensors
function in the instrument cluster control
system.
GWarning!
BAS PLUS will only respond with brake
assistance if it has clearly detected an object.
Detection can be impeded by
R dirty or covered sensors
R snowfall or heavy rain
R disturbance from other radar sources
R strong radar reflection such as in parking
garages
BAS PLUS uses radar signals that are not
reflected well by narrow objects and
absorptive materials. For this reason BAS
PLUS will not react to persons, animals, and
approaching traffic or cross-traffic.
BAS PLUS may not detect narrow vehicles
driving in front of you, such as motorcycles
and vehicles driving offset from your vehicle
center.
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.
Adaptive Brake
Adaptive Brake provides a high level of
braking safety as well as increased braking
comfort. Adaptive Brake takes driver and
vehicle characteristics into consideration,
thus achieving an optimal braking effect.
In addiditon, Adaptive Brake provides the
HOLD function (Y page 161) and the hill-start
assist system ( Y page 160).
For more information on the brake system,
see ( Y page 254).
EBP
GObserve Safety notes, see page 62.
The Electronic Brake Proportioning (EBP)
enhances braking effectiveness by allowing
the rear brakes to supply a greater proportion
of the braking effort in straight-line braking
without a loss of vehicle stability.
GWarning!
If the EBP malfunctions, the brake system will
still function with full brake boost. However,
the rear wheels could lock up during
emergency braking situations, for example.
You could lose control of the vehicle and
cause an accident.
Adapt your driving style to the changed
driving characteristics.
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