Page 57 of 430

R
if, on vehicles with DISTRONIC PLUS, the
radar sensor system detects an imminent
danger of collision in certain situations.
R in critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely.
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
R the front-passenger seat is adjusted if it is
in an unfavorable position.
R the air pressure in the side bolsters of the
seat cushion and seat backrest of the front
active multicontour seats is increased.
R if the vehicle skids, the sliding sunroof and
the side windows are closed so that only a
small gap remains. On vehicles with a
panorama roof with power tilt/sliding
panel, they are closed completely.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. The air pressure in
the side bolsters of the active multicontour
seat is reduced again. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:
X When the vehicle is stationary, move the
backrest or seat back slightly.
The seat belt pre-tensioning is reduced and
the locking mechanism is released.
Information about seat belt adjustment, a
convenience function integrated into PRE-
SAFE ®
, can be found in the "Seat belt
adjustment" section (Y page 57).Seat belts
Important safety notes G
WARNING
The seat belt does not offer the intended level
of protection if the backrest is not in the
upright position. When braking or in the event of an accident, you could slide underneath the
seat belt and sustain abdomen or neck
injuries, for example. This poses an increased
risk of injury or even fatal injury.
Adjust the seat properly before beginning
your journey. Always make sure that the seat
is in the upright position.
G
WARNING
Seat belts cannot protect as intended, if:
R they are damaged, extremely dirty,
bleached or dyed
R the seat belt buckle is damaged or
extremely dirty
R the Emergency Tensioning Devices or the
belt anchorage has been modified.
Damage caused to seat belts in an accident
may not be visible, e.g. by splinters of glass.
Modified or damaged seat belts can tear or
fail, for example in the event of an accident.
Modified Emergency Tensioning Devices may
be deployed unintentionally or fail to be
deployed when required. There is an
increased risk of injury, possibly even fatal.
Never modify seat belts, Emergency
Tensioning Devices, seat belt anchorages and
inertia reels. Ensure that seat belts are not
damaged or worn and are clean.
Only use seat belts that have been approved
for your vehicle by Mercedes-Benz.
The use of seat belts and infant and child
restraint systems is required by law in:
R all 50 states
R the U.S. territories
R the District of Columbia
R all Canadian provinces
Even where this is not required by law, all
vehicle occupants should correctly fasten
their seat belts before starting the journey.
i See "Children in the vehicle"
(Y page 60) for further information on
infants and children traveling in the vehicle
as well as on child restraint systems. Occupant safety
55Safety Z
ProCarManuals.com
Page 58 of 430

Correct use of the seat belts
G
WARNING
USE SEAT BELTS PROPERLY
R Seat belts can only work when used
properly. Never wear seat belts in any other
way than as described in this section, as
that could result in serious injuries in the
event of an accident.
R Each occupant should wear their seat belt
at all times, because seat belts help reduce
the likelihood of and potential severity of
injuries in accidents, including rollovers.
The integrated restraint system includes
SRS (driver front air bag, driver's side knee
bag, front-passenger front air bag, side
impact air bags, pelvis air bags, window
curtain air bags for the side windows),
Emergency Tensioning Devices, seat belt
force limiters, and front seat knee bolsters.
The system is designed to enhance the
protection offered to properly belted
occupants in certain frontal (front air bags,
driver's side knee bag and ETDs) and side
(side impact air bags, window curtain air
bags, and ETDs) impacts which exceed
preset deployment thresholds and in
certain rollovers (window curtain air bags
and ETDs).
R Never wear the shoulder belt under your
arm, across your neck or off your shoulder.
In a frontal crash, your body would move
too far forward. That would increase the
chance of head and neck injuries. The seat
belt would also apply too much force to the
ribs or abdomen, which could severely
injure internal organs such as your liver or
spleen.
Adjust the seat belt so that the shoulder
section is located as close as possible to
the middle of the shoulder. It should not
touch the neck. Never pass the shoulder
portion of the seat belt under your arm. For
this purpose, you can adjust the height of
the seat belt outlet. R
Position the lap belt as low as possible on
your hips and not across the abdomen. If
the lap belt is positioned across your
abdomen, it could cause serious injuries in
a crash.
R Never wear seat belts over rigid or
breakable objects in or on your clothing,
such as eyeglasses, pens, keys etc., as
these might cause injuries.
R Make sure the seat belt is always fitted
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.
Fastening seat belts G
WARNING
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 56
Occupant safetySafety
ProCarManuals.com
Page 59 of 430

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. Seat belt (example: Sedan)
X
Adjust the seat and move the backrest to
an almost vertical position (Y page 108).
X Pull the seat belt smoothly through belt
sash guide :.
X Without twisting it, guide the shoulder
section of the seat belt across the middle
of your shoulder and the lap section across
your pelvis.
X Engage 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 57). X
If necessary, adjust the seat belt to the
appropriate height (Y page 58).
X If necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
All seat belts in the vehicle with the exception
of the driver's seat belt and the seat belt on
the folding bench seat in the cargo
compartment are equipped with a special
seat belt retractor, to which a child restraint
system can be secured. Further information
can be found under "Special seat belt
retractor" (Y page 63).
Information on releasing the seat belt with
release button ?(Ypage 58).
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 2in the ignition lock.
R the SmartKey is in position 2in 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 252).
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. More
information about PRE-SAFE ®
can be found
under "PRE-SAFE ®
(preventative occupant
protection)" (Y page 54). Occupant safety
57Safety Z
ProCarManuals.com
Page 60 of 430

Belt height adjustment
You can adjust the seat belt height on the
front seats. Wagon:you can also adjust the
belt height on the outer rear seats. Adjust the
belt to a height that allows the upper part of
the seat belt to be routed across the center
of your shoulder.
X To raise: slide the belt sash guide upwards.
The belt sash guide engages in various
positions.
X To lower: press and hold belt sash guide
release :.
X Slide the belt sash guide downwards.
X Release belt sash guide release :and
make sure that the belt sash guide has
engaged.
Using the rear center seat belt If the left-hand rear seat backrest is folded
down and back up again, the rear center seat
belt may lock. The seat belt can then not be
pulled out.
X To release the rear center seat belt: pull
out the seat belt by the belt outlet on the
backrest approximately 1 in (25 mm) and
release it again.
The seat belt is retracted and released.
Releasing seat belts !
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. Visit a qualified specialist
workshop.
Seat belt (example: Sedan)
X
Press release button ?on belt buckle =.
X Guide belt tongue ;to belt sash
guide :.
Belt warning for the driver and front
passenger Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7seat belt warning lamp
lights up for six seconds each time the engine
is started. It then goes out if the driver and
the front passenger have already fastened
their seat belts.
If the driver's seat belt is not fastened when
the engine is started, an additional warning
tone will sound. This warning tone stops after
a maximum of six seconds or once the
driver's seat belt is fastened. 58
Occupant safetySafety
ProCarManuals.com
Page 61 of 430

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 lit
as long as the driver's or front-passenger's
seat belt is not fastened
and
R if a vehicle speed of 15 mph (25 km/h) is
exceeded, the 7seat belt warning lamp
begins to flash. A warning tone also sounds
with increasing intensity for a maximum of
60 seconds or until the driver or front
passenger have fastened their seat belts.
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 seat belt has still not been
fastened after 60 seconds. The 7seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the seat belt
warning lamp 7flashes 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 7seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" (Y page 285).
Emergency Tensioning Devices, seat
belt force limiters G
WARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed are no longer
operational and are unable to perform their intended protective function. This poses an
increased risk of injury or even fatal injury.
Therefore, have pyrotechnic Emergency
Tensioning Devices which have been
triggered immediately replaced at a qualified
specialist workshop.
! 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.
i Vehicles with PRE-SAFE ®
: Emergency
Tensioning Devices that are triggered by an
electric motor can be deployed as often as
desired and do not need to be replaced.
The front seat belts and the outer seat belts
in the rear are equipped with Emergency
Tensioning Devices 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.
The ETDs can only be activated when:
R the ignition is switched on
R the restraint systems are operational; see
"SRS warning lamp 6" (Ypage 41)
R the belt tongue is engaged in the buckle on
each of the front seat belts
The ETDs on the outside 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 Occupant safety
59Safety Z
ProCarManuals.com
Page 62 of 430

direction during the initial stages of the
impact.
R in the event of a side impact if the vehicle
decelerates or accelerates rapidly in a
lateral direction on the side opposite to the
impact.
R in certain situations where the vehicle rolls
over if the system determines that it can
provide additional protection.
If the ETDs 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 and does not indicate that there
is a fire in the vehicle. The dust might cause
some temporary breathing difficulty for
people with asthma or other breathing
trouble. To avoid this, you may wish to get out
of the vehicle as soon as it is safe to do so.
You can also open the window to allow fresh
air to enter the vehicle interior. The 6SRS
warning lamp lights up.
If the seat belt is also equipped with a seat
belt force limiter and this is triggered, the
force exerted by the seat belt on the vehicle
occupant is reduced.
The seat belt force limiters for the front seats
are synchronized with the front air bags,
which absorb part of the deceleration force.
This results in the force exerted on the
occupant being distributed over a greater
area. Children in the vehicle
Child restraint systems
Important safety notes G
WARNING
According to accident statistics, children are
safer when properly restrained in the rear
seating positions than in the front seating
position. 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 appropriate
infant restraint, toddler restraint, or booster
seat recommended for the size and weight of
the child.
The infant or child restraint 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 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. 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 For children larger than the typical
12-month-old child, the front passenger
front air bag may or may not be activated.
Always make sure the 45indicator
lamp is illuminated, indicating that the front
passenger front air bag is deactivated.
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
completely eliminate this risk is to never
place a child in a rear-facing child restraint
in the front seat. We therefore strongly 60
Children in the vehicleSafety
ProCarManuals.com
Page 63 of 430

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 45indicator
lamp is illuminated, indicating that the front
passenger front air bag is deactivated.
Should the 45indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check the 45indicator
lamp while driving to make sure the 4
5 indicator lamp is illuminated. If the
45indicator 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. G
WARNING
If the child restraint system is installed
incorrectly on a suitable seat, it cannot
protect as intended. The child cannot then be
restrained in the event of an accident, heavy
braking or sudden changes of direction. There
is an increased risk of injury, possibly even
fatal.
Make sure that you observe the child restraint
system manufacturer's installation
instructions and the notes on use. Please
ensure, that the base of the child restraint
system is always resting completely on the
seat cushion. Never place objects, e.g.
cushions, under or behind the child restraint system. Only use child restraint systems with
the original cover designed for them. Only
replace damaged covers with genuine covers.
G
WARNING
If the child restraint system is installed
incorrectly or is not secured, it can come
loose in the event of an accident, heavy
braking or a sudden change in direction. The
child restraint system could be thrown about,
striking vehicle occupants. There is an
increased risk of injury, possibly even fatal.
Always install child restraint systems
properly, even if they are not being used.
Make sure that you observe the child restraint
system manufacturer's installation
instructions. G
WARNING
Child restraint systems or their securing
systems which have been damaged or
subjected to a load in an accident can no
longer protect as intended. The child cannot
then be restrained in the event of an accident,
heavy braking or sudden changes of direction.
There is an increased risk of injury, possibly
even fatal.
Replace child restraint systems which have
been damaged or subjected to a load in an
accident as soon as possible. Have the
securing systems on the child restraint
system checked at a qualified specialist
workshop, before you install a child restraint
system again. G
WARNING
Infants and small children should never share
a seat belt with another occupant. In the event
of 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 in the vehicle
61Safety
Z
ProCarManuals.com
Page 64 of 430

Children that are too large for a child restraint
must travel in seats using normal seat belts.
Position the shoulder belt across the chest
and shoulder, not the face or neck. A booster
seat may be necessary to achieve proper seat
belt positioning for children over 41 lbs
(18 kg) until they reach a height where a lap/
shoulder belt fits properly without a booster
seat.
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. G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. G
WARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Children may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight.
Protect it with a blanket, for example. If the
child restraint system has been exposed to
direct sunlight, let it cool down before
securing the child in it. Never leave children
unattended in the vehicle.
If an infant or child is traveling in the vehicle:
R Secure the child with a child or infant seat
restraint system appropriate to the age and
weight of the child.
R Make sure that the infant or child is
properly secured at all times while the
vehicle is in motion.
Mercedes-Benz recommends that you always
properly secure all infants and children with
a child or infant seat restraint system for the
trip.
The use of seat belts and infant and child
restraint systems is required by law in:
R all 50 states
R the U.S. territories
R the District of Columbia
R 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
the following standards:
R U.S. Federal Motor Vehicle Safety
Standards 213 and 225
R Canadian Motor Vehicle Safety Standards
213 and 210.2
Confirmation that the child restraint system
corresponds to the standards can be found
on an instruction label on the child restraint
system. This confirmation can also be found 62
Children in the vehicleSafety
ProCarManuals.com