
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 54).
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.
If necessary, adjust the tilt of the passenger
seat backrest.
An incorrectly mounted child seat could cause
injuries to the child in case of an accident,
instead of increasing protection for the child.
Follow the manufacturer's instructions for
installation of child restraint systems.
Occupant safety53SafetyZ

Problems with the occupant classification systemProblemPossible causes/consequences and M SolutionsThe 42
indicator lamp
illuminates and
remains illuminated.
The person on the
front-passenger seat:
R has the weight of a
typical adult
R has been determined
by the system not to
be a child.The OCS is malfunctioning.XHave the OCS checked as soon as possible at an authorized
Mercedes-Benz Center.XObserve the additional display messages in the multifunction
display ( Y page 399).GWARNING
If the 42 indicator lamp illuminates and remains illuminated when the weight of a
typical adult or someone larger than a small individual has been detected on the passenger seat,
the system then determines the occupant cannot be a child. Do not allow any occupant to use
the passenger seat until the system has been repaired.
ProblemPossible causes/consequences and M SolutionsThe 42
indicator lamp does not
illuminate and/or does
not remain illuminated.
The front-passenger
seat is:
R unoccupied
R occupied with a
weight up to or less
than a typical 12-
month-old child in a
standard child
restraint systemThe OCS is malfunctioning.XMake sure there is nothing between the seat cushion and the
child seat.XCheck the installation of the child restraint system.XMake sure that no objects are applying additional weight onto
the seat.XIf the 42 indicator lamp does not illuminate, have
the OCS checked as soon as possible at an authorized
Mercedes-Benz Center. Do not transport a child on the front-
passenger seat as long as the OCS is not functioning.XObserve the additional display messages in the multifunction
display ( Y page 399).GWARNING
If the 42 indicator lamp does not illuminate or remains out with the weight of a
typical 12-month-old child in a standard child restraint or less, or is unoccupied, on the front-
passenger seat, do not transport a child on the front-passenger seat until the system has been
repaired.
54Occupant safetySafety

XPress the base of the NECK-PRO head
restraint cushion back in the direction of
arrow ; as far as it will go.XPush the NECK-PRO head restraint cushion
down into the guide in the direction of
arrow = as far as it will go.XFirmly fold the NECK-PRO head restraint
cushion back in the direction of arrow :
until it engages.XRepeat this procedure for the second
NECK-PRO head restraint.
NECK-PRO luxury head restraints
i If you have difficulty resetting the NECK-
PRO luxury head restraints, have this work
carried out at a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center.
XRemove resetting tool : from the vehicle
tool kit in the trunk.XSlide resetting tool : into guide ;
between the NECK-PRO luxury head
restraint and the rear cover of the head
restraint.XPush resetting tool : downwards until you
hear the head restraint deployment
mechanism engage.XPull out resetting tool :.XFirmly press the NECK-PRO luxury head
restraint cushion back = until it engages.XRepeat this procedure for the second
NECK-PRO luxury head restraint.XPut resetting tool : back into the vehicle
tool kit.
Seat belts
Important safety notes
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.
Even where this is not the case, all vehicle
occupants should have their seat belts
fastened when the vehicle is in motion.
i For further information on infants and
children traveling in the vehicle and on
infant and child restraint systems, see
"Children in the vehicle" ( Y page 62).
GWARNING
Always fasten your seat belt before driving off.
Always make sure all of your passengers are
properly restrained. You and your passengers
should always wear seat belts.
Failure to wear and properly fasten and
position your seat belt greatly increases your
risk of injuries and their likely severity in an
accident.
If you are ever in an accident, your injuries can
be considerably more severe without your
seat belt properly buckled. Without your seat
belt buckled, you are much more likely to hit
the interior of the vehicle or be ejected from
it. You can be seriously injured or killed.
In the same crash, the possibility of injury or
death is lessened if you are properly wearing
your seat belt. The air bags can only protect
as intended if the occupants are properly
wearing their seat belts.
GWARNING
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
Occupant safety57SafetyZ

RMake sure the seat belt is always routed
snugly. Take special care of this when
wearing loose clothing.
R Never use a seat belt for more than one
person at a time. Do not fasten a seat belt
around a person and another person or
other objects at the same time.
R Seat belts should not be worn twisted. In a
crash, you would not have the full width of
the seat belt to distribute impact forces.
The twisted seat belt against your body
could cause injuries.
R Pregnant women should also always use a
lap-shoulder belt. The lap belt portion
should be positioned as low as possible on
the hips to avoid any possible pressure on
the abdomen.
R Place the seat backrest in a position that is
as upright as possible.
R Check your seat belt during travel to make
sure it is properly positioned.
R Never place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
R When using a seat belt to secure infant
restraints, toddler restraints, or children in
booster seats, always follow the child seat
manufacturer's instructions.GWARNING
Do not pass seat belts over sharp edges. They
could tear.
Do not allow the seat belt to get caught in the
door or in the seat adjustment mechanism.
This could damage the seat belt.
Never attempt to make modifications to seat
belts. This could impair the effectiveness of
the seat belts.
Fastening seat belts
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 seat 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. For additional information, see the
"Children in the vehicle" section.
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.XAdjust the seat and move the backrest to
an almost vertical position ( Y page 102).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.Occupant safety59SafetyZ

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 60).XIf necessary, adjust the seat belt to the
appropriate height ( Y page 60).XIf necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor to
securely fasten child restraint systems in the
vehicle. For further information on special
seat belt retractors, see ( Y page 64).
For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" ( Y page 60).
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:
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
retraction 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 386).
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. More
information about PRE-SAFE ®
can be found
in the "PRE-SAFE ®
(preventative occupant
protection)" section ( Y page 55).
Belt height adjustment
You can adjust the seat belt height on the
driver's seat and the front-passenger seat.
Adjust the height so that the upper part of the
seat belt is 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.
The seat belts for the outer seats in the rear
are adjusted automatically.
Releasing seat belts
XPress release button ?(Y page 59) 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.
60Occupant safetySafety

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 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.
! 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. In vehicles with a rear
bench seat with electrically adjustable outer
seats, the seat belts for the outer seats 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
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.
62Children in the vehicleSafety

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 42indicator 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.
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 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
Children in the vehicle63SafetyZ

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
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.
64Children in the vehicleSafety