The front air bags increase protection for the
driver's and front-passenger's head and
chest.
Driver's air bag : deploys in front of the
steering wheel; front-passenger air bag ;
deploys in front of and above the glove box.
They are deployed:
Rin the event of certain frontal impacts
Rif the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
Rif the seat belt is fastened
Rindependently of other air bags in the
vehicle
If the vehicle overturns, the front air bags are
generally not deployed unless the system
detects high vehicle deceleration in a
longitudinal direction.
Your vehicle has adaptive, two-stage front air
bags. In the event of a collision, the air bag
control unit evaluates the vehicle
deceleration. When the first deployment
threshold is reached, the front air bag is filled
with enough propellant gas to reduce the risk
of injuries. The front air bag is fully deployed
if a second deployment threshold is exceeded
within a few milliseconds.
Vehicles with OCS (USA only): front-
passenger front air bag deployment is also
influenced by the passenger's weight
category as identified by the Occupant
Classification System (OCS) (Y page 42).
Vehicles with OCS (USA only): the lighter the
passenger side occupant, the higher the
vehicle deceleration rate required for second
stage inflation of the front-passenger front air
bag. In the second stage, the front air bags
are inflated with the maximum amount of
propellant gas available.
In impact situations with deceleration or
acceleration values lower than the vehicle
deceleration or acceleration values preset in
the system, the front air bags are not
deployed. You will then be protected by the
seat belt.
! Vehicles with BabySmart™ (Canada only):
do not place any objects which weigh more
than 20 lb (9 kg) on the front-passenger
seat. This could cause the system to
identify the seat as being occupied. In the
event of an accident, the restraint systems
on the front-passenger side are triggered.
Have restraint systems that have been
triggered replaced.
The front-passenger air bag will only deploy
if:
Rthe system, based on the OCS weight
sensor readings, detects that the front-
passenger seat is occupied (USA only).
Rthe 45 indicator lamp in the center
console is not lit, USA: (Y page 42),
Canada: (Y page 47).
Rthe impact exceeds a preset deployment
threshold.
Driver's knee bag
GWarning
Observe "Important safety notes"
(Y page 36).
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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 that 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 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 the typical 12-
month-old child, the front-passenger front
air bag may or may not be activated.
Deployment of the driver front air bag does
not mean that the front-passenger front air
bag should also have deployed.
OCS may have determined:
R that the seat was unoccupied or occupied
by a weight of up to or less than that of a
typical 12-month-old child seated in a
standard child restraint
R that the seat was occupied by a small
individual (e.g. a young teenager or a small
adult) or a child who weighs more than a
typical 12-month-old child in a standard
child restraint system
These are examples of when OCS deactivates
the front-passenger front air bag. The air bag
is deactivated despite the impact fulfilling the
criteria for deploying the driver's front air bag.
If the SmartKey has been removed from the
ignition lock or is in position 0, indicator lamp
45 : does not light up.
GWarning
If the red 6 SRS warning lamp in the
instrument cluster and the 45
indicator lamp light up simultaneously, the
OCS is malfunctioning. The front passenger
front air bag will be deactivated in this case.
Have the system checked by qualified
technicians as soon as possible. Contact an
authorized Mercedes-Benz Center.
Only have the seat repaired or replaced at an
authorized Mercedes-Benz Center.
In order to ensure proper operation of the air
bag system and OCS:
R Sit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
R When seated, a passenger should not
position him/herself in such a way as to
cause the passenger's weight to be lifted
from the seat cushion as this may result in
the OCS being unable to correctly
approximate the passenger's weight
category.
R Read and observe all warnings in this
chapter.
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BabySmart™ air bag deactivation
system
How the air bag deactivation system
functions
The BabySmart™ system is standard
equipment in Canada.
GWarning
According to accident statistics, children are
safer when properly restrained on the rear
seats than on the front-passenger seat. For
this reason, Mercedes-Benz strongly advises
that you always secure children in the rear
seats. 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.
Secure the infant restraint system or child
restraint system, using:
R the vehicle's seat belt
R the seat belt and a Top Tether belt
R the LATCH-type (ISOFIX) child seat mount
and a Top Tether belt
The child restraint system must be installed
and secured correctly, observing the
manufacturer's installation instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriately 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. Observe the following
important information if it is necessary to
carry a child on the front-passenger seat:
R Children under 12 years may only sit in the
front-passenger seat if they are seated in a
child restraint system which is compatible
with BabySmart™ and approved by
Mercedes-Benz. If the child restraint
system is installed properly, the front-
passenger front air bag is deactivated in
conjunction with the BabySmart™ system.
Otherwise, the child could be struck by the
air bag when it inflates in a crash. This could
lead to serious or fatal injury.
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 it is necessary to install a BabySmart™-
compatible rear-facing child restraint
system on the front-passenger seat, make
sure the 45 indicator lamp is
illuminated. This indicates that the front-
passenger front air bag is deactivated. If the
45 indicator lamp does not light up
or goes out when the child restraint system
is installed, check the anchorages of the
restraint system. Periodically check the
45 indicator lamp while driving to
make sure the 45 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 seriouslyOccupant safety47SafetyBA 207 USA, CA Edition B 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.62010-05-20T10:38:09+02:00 - Seite 47Z
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 system on the front-
passenger seat, you must:
- 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 instructionsGWarning
The BabySmart™ air bag disabling system
ONLY works with specially adapted child
restraint systems. It does not work with child
restraint systems that are not compatible with
BabySmart™.
Never place anything between the seat
cushion and the child restraint system (e.g. a
cushion), as this reduces the effectiveness of
the BabySmart™ air bag deactivation system.
The underside of the child restraint system
must lie against the seat cushion of the front-
passenger seat. In the event of an accident,
an incorrectly installed child restraint system
could injure the child instead of offering
protection.
Observe the manufacturer's instructions
when installing special child restraint
systems.
GWarning
When using a BabySmart™-compatible child
restraint system on the front-passenger seat,
the front-passenger front air bag is only
disabled if the 45 indicator lamp is
illuminated.
Check the 45 indicator lamp
repeatedly, every time you use a
BabySmart™-compatible child restraint
system on the front-passenger seat. Should
the 45 indicator lamp not illuminate
or go out while the restraint is installed,
please check installation. If the 45
indicator lamp remains out, do not use the
BabySmart™ child restraint system to carry a
child on the front-passenger seat until the
system has been repaired.
Special child restraint systems which are
compatible with BabySmart™ are necessary
for deactivating the front-passenger front air
bag. When the special child restraint system
which is compatible with BabySmart™ is
installed correctly and is recognized by the
sensor system in the front-passenger seat,
the front-passenger front air bag is
deactivated. In this case, 45 indicator
lamp : illuminates. If you have any
questions regarding the special child
restraint systems which are compatible with
BabySmart™, consult an authorized
Mercedes-Benz Center.
If the key has been removed from the ignition
lock or is in position 0, indicator lamp
45 : does not light up.
The system does not deactivate:
R the side impact air bag
R the pelvis air bag
R the front passenger head bag (Cabriolet)
R the window curtain air bag (Coupe)
R the Emergency Tensioning Devices
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workshop immediately and have the roll bar
checked.
PRE-SAFE ®
system
GWarning
The PRE-SAFE ®
system reduces the impact of
an accident on vehicle occupants, as long as
their seat belts have been fastened correctly.
Although your vehicle is equipped with a PRE-
SAFE ®
system, the possibility of injury in the
event of an accident cannot be ruled out. You
should therefore always drive carefully and
adapt your driving style to the prevailing road,
weather and traffic conditions.
PRE-SAFE ®
takes pre-emptive measures to
protect the occupants in certain hazardous
situations.
PRE-SAFE ®
intervenes:
R in emergency braking situations, e.g. if BAS
is activated or, on vehicles with DISTRONIC
PLUS, if BAS PLUS or PRE-SAFE ®
Brake
intervenes powerfully
R if the radar sensor system detects an
imminent danger of collision in certain
situations (on vehicles with DISTRONIC
PLUS)
R in critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely
or when having to swerve to avoid an
obstacle at a speed above 85 mph
(140 km/h).
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
R under accident conditions, the front-
passenger seat is adjusted if it is in an
unfavorable position.
R increases the air pressure in the side
bolsters of the seat cushion and seat
backrest of the multicontour seats in the
front.
R Coupe: if the vehicle skids, the panorama
sliding sunroof and the front side windows
are closed so that only a small gap remains.
R Cabriolet: if the vehicle skids, the front side
windows are closed so that only a small gap
remains.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pretensioning. The air pressure in the
side bolsters on the multicontour seat is
reduced again. All settings made by PRE-
SAFE ®
can then be reversed.
If the seat belts are not released:XWhen the vehicle is stationary, move the
backrest or seat back slightly.
The belt pretensioning is reduced and the
locking mechanism is released.GWarning
Make sure that nobody can become trapped
as you adjust the seat.
! Make sure that there are no objects in the
footwell or behind the seats when resetting
the seats. There is a risk that the seats
and/or the objects could be damaged.
More information about belt adjustment, a
convenience function integrated into PRE-
SAFE ®
, can be found in the "Belt adjustment"
section ( Y page 56).
NECK-PRO head restraints
The NECK-PRO head restraints increase
protection for the driver's and front-
passenger's head and neck. In the event of a
rear collision of a certain severity, the NECK-
PRO head restraints on the driver's and front-
passenger seats are moved forwards and
upwards. This provides better head support.
GWarning
Do not secure any objects (e.g. coat hangers)
on the NECK-PRO head restraints. Otherwise,
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Example: Coupe
XAdjust the seat and move the backrest to
an almost vertical position (Y page 106).
XPull the seat belt smoothly out of seat-belt
extender :.
XWithout twisting it, guide the shoulder
section of the seat belt across the middle
of your shoulder and the lap section across
your hips.
XEngage belt tongue ; in buckle =.
Seat belt adjustment: if necessary, the
driver's and front-passenger seat belts
automatically adjust to the upper body
(Y page 56).
XIf necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
All seat belts in the vehicle, except the
driver's seat belt, are equipped with a special
seat belt retractor to secure child restraint
systems properly. For further information on
"Special seat belt retractors", see
(Y page 61).
For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" (Y page 56).
Seat belt adjustment
The seat-belt adjustment function adjusts the
driver's and front-passenger seat belt to the
upper body of the occupants.
The belt strap is tightened slightly when:
Ryou engage the belt tongue in the belt
buckle and you then turn the SmartKey to
position 2 in the ignition lock.
Rthe SmartKey is in position 2 in the ignition
lock and you then engage the belt tongue
in the buckle once the seat-belt extender
has retracted.
The seat-belt adjustment will apply a certain
tightening force if any slack is detected
between the occupant and the seat belt. Do
not hold on to the seat belt tightly while it is
adjusting. You can switch the seat-belt
adjustment on and off in the on-board
computer (Y page 211).
Releasing seat belts
XPress release button ? (Y page 54) and
guide belt tongue ; back towards seat
belt extender :.
! Make sure that the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt.
Damaged seat belts can no longer fulfill
their protective function and must be
replaced. Consult an authorized Mercedes-
Benz Center.
Belt warning for driver and front
passenger
Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7 seat belt warning lamp
lights up for six seconds each time the engine
is started. It then goes out once the driver and
the front passenger have fastened their seat
belts.
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If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If, after six seconds, the driver or front-
passenger have not fastened their seat belts
and the doors are closed:
R the 7 seat belt warning lamp remains
illuminated as long as either the driver's or
front-passenger seat belt is not fastened.
R if the vehicle speed exceeds 15 mph
(25 km/h), the 7 seat belt warning
lamp lights up. Additionally, a warning tone
will sound with increasing intensity for a
maximum of 60 seconds or until the
driver's and front-passenger seat belt are
fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front passenger have still not fastened their
seat belt after 60 seconds. The 7 seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed again exceeds 15 mph (25 km/h) .
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open.
i For more information on the 7 seat
belt warning lamp, see "Indicator and
warning lamps in the instrument cluster,
seat belt" ( Y page 241).Emergency Tensioning Devices and
seat belt force limiters
The seat belts are equipped with ETDs and
belt force limiters.
! 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.
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
ETDs do not correct incorrect seat positions
or incorrectly fastened seat belts.
ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when activated, are
employed to help reduce the force exerted by
the seat belts on occupants during a crash.
The front belt force limiters are synchronized
with the front air bags, which 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 if:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 34).
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 in the event of a head-on or rear-end
collision if the vehicle decelerates or
accelerates rapidly in a longitudinal
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direction during the initial stages of the
impact
R in the event of a side impact, on the side
opposite the impact if the vehicle
decelerates or accelerates rapidly in a
lateral direction
R Cabriolet: in certain situations if the vehicle
overturns and the system determines that
it can provide additional protection.
If the Emergency Tensioning Devices (ETDs)
are triggered, 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 Emergency Tensioning Devices
that have been deployed must be renewed.
For your safety, when disposing of Emergency
Tensioning Devices, always observe the
safety instructions. These are available from
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
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
Important safety notes
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
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