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:
R in the event of certain frontal impacts
R if the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
R if the seat belt is fastened
R independently 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, dual-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.
The air bags will not deploy in impacts which
do not exceed the system's preset
deployment thresholds. You will then be
protected by the seat belt.
! Vehicles with BabySmart™ (Canada only):
do not place objects heavier than 20 lb
(9 kg) on the front-passenger seat, as this
could be interpreted as the seat being
occupied. In the event of an accident, the
restraint systems on the front-passenger
side are deployed. Have restraint systems
replaced that have been deployed.
The front-passenger front air bag will only
deploy if:
R the system, based on the OCS weight
sensor readings, detects that the front-
passenger seat is occupied (USA only).
R the 42 indicator lamp in the
center console is not lit, USA:
( Y page 42), Canada: ( Y page 48).
R the impact exceeds a preset deployment
threshold
Side impact air bagsGWarning
Observe "Important safety instructions"
( Y page 38).
GWarning!
The pressure sensors for side impact air bag
control are located in the doors. Do not
modify any components of the doors or door
trim panels including, for example, the
addition of door speakers.
Improper repair work on the doors or the
modification or addition of components to the
doors create a risk of rendering the side
impact air bags inoperative or causing
unintended air bag deployment. Work on the
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If the key has been removed from the ignition
lock or is in position 0, indicator lamp
42 : does not light up.
GWarning
If the red + SRS warning lamp in the
instrument cluster and the 42
indicator lamp are lit at the same time, there
is a malfunction in the OCS. The front-
passenger front air bag will be deactivated in
this case. Have the system checked as soon
as possible by qualified technicians. 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 Do not place more than 4.4 lb (2 kg) into
the parcel net on the rear of the front-
passenger seat. Otherwise, the OCS may
not be able to properly approximate the
occupant weight category.
R Do not place objects under and/or around
the front-passenger seat.
R Do not hang anything from or attach any
items to the seats.
R Do not store any objects, such as books,
between the front-passenger seat and the
center console or the front-passenger door.
R Do not move the front-passenger seat
backwards against rigid objects.
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 While seated, an occupant should not
position him/herself in such a way as to
cause the occupant's weight to be lifted
from the seat cushion as this may result in
the OCS being unable to correctly
approximate the occupant's weight
category.
R Read and observe all warnings in this
chapter.
System self-test
The 42 indicator lamp
illuminates when you:
R turn the SmartKey to position 1 or 2 in the
ignition lock
R press the KEYLESS-GO Start-Stop button
once or twice
If an adult occupant is properly sitting on the
passenger seat and the OCS classifies the
occupant as an adult, the 42
indicator lamp illuminates and goes out again
after approximately 6 seconds.
If the seat is not occupied and the OCS
classifies the front-passenger seat as being
unoccupied, the 42 indicator
lamp will illuminate and not go out.
GWarning!
If the 4 2 indicator lamp does
not illuminate, the system is not functioning.
You must contact an authorized Mercedes-
Benz Center before seating any child on the
front passenger seat.
For more information, see "Problems with the
occupant classification system"
( Y page 47).
GWarning
Never place anything between seat cushion
and child seat (e.g. a pillow), since it reduces
the effectiveness of the OCS. The underside
and rear side child restraint system must be
placed entirely on the seat cushion and the
backrest of the front-passenger seat
backrest.
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indicator lamp while driving to make sure
that the 42 indicator lamp is
illuminated. If the 42 indicator
lamp goes out or remains out, you may only
carry a child on the front-passenger seat
once 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 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
When using a BabySmart™-compatible child
restraint system on the front-passenger seat,
the front-passenger front air bag is only
disabled if the 42 indicator lamp
is illuminated.
Check the 42 indicator lamp
repeatedly, every time you use a
BabySmart™-compatible child restraint
system on the front-passenger seat. Should
the 42 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation. If the
42 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.
GWarning
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.
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, 42
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
42 : does not light up.
The system does not disable:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices
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PRE-SAFE®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
R on vehicles with memory functions: the
front-passenger seat is adjusted if it is in an
unfavorable position under accident
conditions.
R if the vehicle skids, the side windows are
closed so that only a small gap remains.
R on vehicles with sliding sunroof: if the
vehicle skids, the sliding sunroof closes so
that only a small gap remains.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pretensioning. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:XMove the backrest or the seat back slightly
until the belt pretensioning is reduced.
The locking mechanism releases.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/NECK-
PRO luxury head restraints
NECK-PRO head restraints/NECK-PRO luxury
head restraints increase protection of 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/
NECK-PRO luxury head restraints on the
driver's and the front-passenger seat are
moved forwards and upwards. This provides
better head support.GWarning
Do not attach any objects (e.g. a coat hanger)
to the NECK-PRO head restraints/NECK-PRO
luxury head restraints. Otherwise, the NECK-
PRO head restraints/NECK-PRO luxury head
restraints may not function properly and in
the event of a rear-end collision may not offer
the protection they are designed to provide.
GWarning
Only use seat covers/head restraint covers
that have been tested and approved by
Mercedes-Benz for your vehicle model.
Using seat covers and head restraint covers
other than those recommended may cause a
malfunction when NECK-PRO head
restraints/NECK-PRO luxury head restraints
are triggered or may prevent side impact air
bags/pelvis air bags from deploying.
Consult an authorized Mercedes-Benz Center
regarding availability.
If the NECK-PRO head restraints/NECK-PRO
luxury head restraints have been triggered in
an accident, reset the NECK-PRO head
restraints/NECK-PRO luxury head restraints
on the driver's and front-passenger seats
( Y page 53). Otherwise, the additional
protection will not be available in the event of
another rear-end collision. NECK-PRO head
restraints/NECK-PRO luxury head restraints
that have been triggered are moved forwards
and can no longer be adjusted.
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.
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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.GWarning
Canada only: children 12 years old and under
may ride on the front seat if a BabySmart™
compatible child restraint system is installed
on the front-passenger seat. Use only
Mercedes-Benz approved BabySmart™
compatible child restraint systems. A
BabySmart™ compatible child restraint
system will deactivate the front-passenger
front air bag when installed correctly. The
front-passenger front air bag will not be
deactivated if the child restraint systems that
are installed are not BabySmart™ compatible
or if BabySmart™ compatible child restraint
systems are not installed correctly. If the
front-passenger front air bag is deployed in a
collision, the child could be struck by the air
bag. This could lead to serious or fatal injury.
XAdjust the seat and move the backrest to
an almost vertical position ( Y page 98).XPull the seat belt smoothly through belt
sash guide :.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, adjust the seat belt to the
appropriate height ( Y page 57).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 57).
Seat belt adjustment
The 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:
R you engage the belt tongue in the belt
buckle and you then turn the SmartKey to
position 2 in the ignition lock.
R the SmartKey is in position 2 in the ignition
lock and you then engage the belt tongue
in the buckle.
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 belt adjustment
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on and off in the on-board computer
( Y page 209).
Seat belt outlet height adjustment
You can adjust the seat belt height on the
driver's seat and the front-passenger seat.
Adjust the belt to a height that allows the
upper part of the seat belt to be routed across
the center of your shoulder.
XTo raise: slide the belt sash guide upwards.
The belt sash guide engages in various
positions.XTo lower: press and hold belt sash guide
release :.XSlide the belt sash guide downwards.XRelease belt sash guide release : and
make sure that the belt sash guide has
engaged.
Releasing seat belts
XPress release button ? (Y page 55) and
guide belt tongue ; back towards belt
sash guide :.
!
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.
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 once 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 continues to
be illuminated.
After the vehicle has come to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed has exceeded 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
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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 237).
Emergency Tensioning Devices and
seat belt force limiters
The seat belts for the following seats are
equipped with ETDs and belt force limiters:
R driver's and front-passenger seat
R the outer seats in the second row
R the seats in the third row
! 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 belt tensioners 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 belt tensioners can only be activated
when:
R the ignition is switched on
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 36)
R
the belt tongue is engaged in the buckle on
each of the three-point seat 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 outside seats in the second
row and on the seats in the third row 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
direction during the initial stages of the
impact
R in the event of a side impact if the vehicle
is subjected to high lateral acceleration/
deceleration.
R in certain situations if the vehicle overturns
and 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 + 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 instructions are available
from any authorized Mercedes-Benz Center.
The PRE-SAFE ®
system is equipped with
electrically resettable seat belt tensioners
that do not need replacing after deployment.
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Children in the vehicle
Important safety guidelines
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
If an infant or child is traveling in the vehicle:XSecure the child using an infant or child
restraint system appropriate to the age and
weight of the child.XMake sure that the infant or child is
properly secured at all times while the
vehicle is in motion.
Child restraint systems
Important safety guidelines
GWarning
Observe "Important safety instructions"
( Y page 59).
We recommend all infants and children be
properly restrained using the child restraint
systems at all times while the vehicle is in
motion.
The use of infant or child restraints is required
by law in all 50 states, the District of
Columbia, the U.S. territories and all
Canadian provinces.
Infants and small children should always be
seated in an infant or child seat restraint
system appropriate for the size and weight of
the child. They must be properly secured in
accordance with the manufacturer's
installation instructions for the infant or child
seat restraint system. All infant and child seat
restraint systems must comply with the US
Federal Motor Vehicle Safety Standards 213
and 225 and Canadian Motor Vehicle Safety
Standards 213 and 210.2.
A statement by the child restraint
manufacturer of compliance with these
standards can be found on the instruction
label on the restraint system. You will also
find the statement in the instruction manual
provided with the child restraint system.
When using any infant restraint, child
restraint or booster seat, make sure to
carefully read and follow all manufacturer's
instructions for installation and use.
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