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Emergency Tensioning Device and seat
belt force limiters
The seat belts are equipped with ETDs and
seat belt force limiters.
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
The ETDs do not correct incorrect seat
positions or incorrectly fastened seat belts.
The ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when triggered, help
to reduce the peak force exerted by the seat
belt on the vehicle occupant.
The seat belt force limiters for the front seats
are synchronized with the front air bags.
These take on a part of the deceleration force.
Thus, the force exerted on the occupant is
distributed over a greater area.
The ETDs can only be activated when:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 40).
R the belt tongue is engaged in the buckle on
each of the lap-shoulder belts in the front.
R the front-passenger seat is occupied and
the belt tongue is engaged in the buckle on
the front-passenger side.
The ETDs on the seats in the rear
compartment are triggered independently of
the lock status of the seat belts.
The ETDs are triggered depending on the type
and severity of an accident:
R if, in the event of a head-on or rear-end
collision, the vehicle decelerates or
accelerates rapidly in a longitudinal
direction during the initial stages of the
impact
R if, in the event of a side impact, on the side
opposite the impact the vehicle
decelerates or accelerates rapidly in a
lateral direction
R if, in certain situations where the vehicle
overturns, the system determines that it
can provide additional protection
If the air bags are deployed, you will hear a
bang, and a small amount of powder may also
be released. Only in rare cases will the bang
affect your hearing. The powder that is
released generally does not constitute a
health hazard. The 6 SRS warning lamp
lights up.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.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device could be triggered in the
event of an accident.
Automatic comfort-install feature
The front seat belts have an automatic
comfort-install feature. The automatic
comfort-install feature reduces the retraction
force of the seat belts. This results in
increased seat belt comfort.
Children in the vehicle
Child restraint systems
Important safety notes
We recommend that all infants and children
be properly secured in an infant or child
restraint system at all times while the vehicle
is in motion.
The use of seat belts and infant and child
restraint systems is required by law in all 50
states, the District of Columbia, the U.S.
territories and all Canadian provinces.
Infants and children must always be seated in
an appropriate infant or child restraint system
recommended for the size and weight of the
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child. The infant or child restraint system
must be properly secured in accordance with
the manufacturer's instructions. All infant or
child restraint systems must meet U.S.
Federal Motor Vehicle Safety Standards 213
and 225 and Canadian Motor Vehicle Safety
Standards 213 and 210.2.
An information label on the child restraint
system indicates whether it meets these
standards. This information is also provided
in the installation instructions supplied with
the child restraint system.
Always read and follow the manufacturer's
instructions when using an infant or child
restraint system or booster seat.
Observe all warning signs in the vehicle
interior and on the infant or child restraint.GWARNING
According to accident statistics, children are
safer when properly restrained on the rear
seats than on the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seats whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriately sized
child restraint system or booster seat
recommended for the size and weight of the
child.
The infant or child restraint system must be
properly secured with the vehicle's seat belt,
the seat belt and Top Tether strap, or lower
anchors and Top Tether strap, fully in
accordance with the child seat
manufacturer's instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriate sized infant
restraint, toddler restraint, or booster seat
recommended for the size and weight of the
child.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front-
passenger seat:
R Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropriate
child restraint on the front-passenger seat.
R 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 in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to eliminate
this risk completely is never to place a child
in a rear-facing child restraint in the front-
passenger seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint on the rear
seat.
R If you install a rear-facing child restraint on
the front-passenger seat, make sure the
42 indicator lamp is
illuminated, indicating that the front-
passenger front air bag is deactivated.
Should the 42 indicator lamp
not illuminate or go out while the restraint
is installed, please check installation.
Periodically check the 42
indicator lamp while driving to make sure
the 42 indicator lamp is
illuminated. If the 42 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.56Children in the vehicleSafety
Page 59 of 488

RIf you 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
- secure child restraint with the vehicle's
seat belt according to the child seat
manufacturer's instructions
R For children larger than a typical 12-month-
old child, the front-passenger front air bag
can be activated or deactivated.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
the shoulder belt across the 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.
If an infant or child is traveling in the vehicle:
XSecure the infant or child with an
appropriate infant or child restraint
recommended for the child's age and
weight.XMake sure that the infant or child is
properly secured at all times while the
vehicle is in motion.GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned on these
parts.
GWARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident
Special seat belt retractor
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor.
When activated, the special seat belt
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retractor ensures the seat belt will not
slacken once the child restraint system has
been secured.
Installing a child restraint system:XAlways comply with the manufacturer's
installation instructions.XPull the seat belt smoothly from the inertia
reel.XEngage the seat belt tongue in the belt
buckle.
Activating the special seat belt retractor:
XPull the seat belt out fully and let the inertia
reel retract it again.
While the seat belt is retracting, you should
hear a ratcheting sound. The special seat
belt retractor is enabled.XPush down on the child restraint system to
take up any slack.
Removing a child restraint system/
deactivating the special seat belt retractor:
XAlways comply with the manufacturer's
installation instructions.XPress the seat belt release button and
guide the belt tongue to the belt outlet.
The special seat belt retractor is
deactivated.GWARNING
Never release the seat belt buckle while the
vehicle is in motion, since the special seat belt
retractor will be deactivated.
LATCH-type (ISOFIX) child seat anchors
in the rear
GWARNING
Children that are too large for a child restraint
must travel in seats using normal seat belts.
Position shoulder belt across the chest and
shoulder, not face or neck.
In order to attain the correct seating position
for children weighing over 41 lb (18 kg), it may
be necessary to use a booster seat until they
reach a height where a normal lap/shoulder
seat belt lies properly across their bodies
without the need for a booster seat.
Install the child restraint system according to
the manufacturer's instructions.
The child restraint system must be installed
firmly on both brackets.
An incorrectly installed child restraint system
can come loose in the event of an accident,
causing the child to be severely or fatally
injured.
Child restraint systems/child restraint
retaining brackets that are damaged or have
suffered damage due to an impact must be
replaced.
LATCH-type (ISOFIX) is a standardized
securing system for specially designed child
restraint systems on the rear seats. Securing
rings for two LATCH-type (ISOFIX) child
restraint systems are installed on the left and
right of the rear seats.
Secure non LATCH-type (ISOFIX) child
restraint systems using the vehicle's seat belt
system. Always install child restraint systems
according to the manufacturer's instructions.
Installation instructions : indicate the
installation location of securing rings 2.
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XFold upholstery cover = and the Velcro
fastener upwards.XTurn installation aid ? to a vertical position
to prevent upholstery cover = from folding
down.XInstall the LATCH-type (ISOFIX) child
restraint systems on both securing
rings ;. Comply with the manufacturer's
instructions when installing the LATCH-
type (ISOFIX) child restraint system.
Top Tether
Top Tether provides an additional connection
between the child restraint system secured
with ISOFIX and the rear seat. It helps reduce
the risk of injury even further.
The Top Tether anchorage points are located
in the rear compartment behind the head
restraints.
XRemove respective covering cap : of the
Top Tether anchorage.XPlace covering cap : in a suitable place
(e.g. in the glove box).XMove the head restraint upwards.XRoute Top Tether belt ? under the head
restraint between the two head restraint
bars.XHook Top Tether hook = of Top Tether
belt ? into Top Tether anchorage ;.
Ensure that:
R Top Tether hook = is hooked into Top
Tether anchorage ; as shown.
R Top Tether belt ? is not twisted.
R Top Tether belt ? can move freely
between the rear seat backrest and the
head restraint.XInstall the LATCH-type (ISOFIX) child
restraint system with Top Tether. Comply
with the manufacturer's installation
instructions when doing so. Make sure that
Top Tether belt ? is tight.
The child restraint system with Top Tether
belt ? has been removed:
XSlide covering cap : onto Top Tether
anchorage ;.Children in the vehicle59SafetyZ
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Child-proof locks
Important safety notesGWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned on these
parts.
Override feature for the rear side
windows
GWARNING
When children ride on the vehicle's rear seats,
activate the override switch. Otherwise the
children could be injured, e.g. by trapping
themselves in the rear side window.
XTo activate/deactivate: press button :.
If indicator lamp ; is lit, operation of the
rear side windows is deactivated.
Operation is only possible using the
switches in the driver's door. If indicator
lamp ; is off, operation is possible using
the switches in the rear compartment.
Panic alarm
X To activate: press ! button : for at
least one second.
An alarm sounds and the exterior lighting
flashes.XTo deactivate: press ! button :
again.
or
XInsert the SmartKey into the ignition lock.
or
XPress the KEYLESS-GO Start/Stop button.
The KEYLESS-GO key must be in the
vehicle.60Panic alarmSafety
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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.
The product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
i Canada only:
This device complies with RSS-Gen 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.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
The product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
Driving safety systems
Driving safety systems overview
In this section, you will find information about
the following driving safety systems:
R ABS ( Anti-lock Braking System)
R BAS ( Brake Assist System)
R BAS PLUS ( Brake Assist System Plus*)
R ESP ®
(E lectronic Stability Program)
R EBD ( Electronic Brake force Distribution)
R ADAPTIVE BRAKE
R PRE-SAFE ®
Brake
Important 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.
i Please note that the driving safety
systems described only work as effectively
as possible when there is adequate contact
between the tires and the road surface. Pay
particular attention to the information
regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and
tires" section ( Y page 442).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible.
Driving safety systems61SafetyZ
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ABS (Anti-lock Braking System)
Important safety notes
i Observe the "Important safety notes"
section ( Y page 61).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about
5 mph(8 km/h) upwards, regardless of road-
surface conditions. ABS works on slippery
surfaces, even when you only brake gently.
GWARNING
If the ABS malfunctions, other driving systems
such as the BAS or the ESP ®
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 the steering
capability and extending the braking distance.
The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Braking
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
XIf ABS intervenes: continue to depress the
brake pedal with force until the braking
situation is over.XTo make a full brake application:
depress the brake pedal with full force.
The pulsating brake pedal can be an
indication of hazardous road conditions, and
functions as a reminder to take extra care
while driving.
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.
BAS (Brake Assist System)
i Observe the "Important safety notes"
section ( Y page 61).
BAS operates in emergency braking
situations. If you depress the brake pedal
quickly, BAS automatically boosts the braking
force, thus shortening the stopping distance.
XKeep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is 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 (Brake Assist System Plus)
BAS PLUS is only available in vehicles
equipped with DISTRONIC PLUS.
i Observe the "Important safety notes"
section ( Y page 61).
At speeds above approximately
4 mph (7 km/h), BAS PLUS assists you when
braking in hazardous situations and uses the
radar sensor system to evaluate the traffic
conditions.
i This device has been approved by the FCC
as a "Vehicular Radar System". The radar
sensor system is intended for use in an
automotive radar system only. Removing,
altering or tampering with 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.
62Driving safety systemsSafety