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G
WARNING
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.
The PASSENGER AIR BAG OFF indicator lamp
lights up:
R if you turn the SmartKey in the ignition lock
to position 1or 2
R if you press the KEYLESS-GO Start/Stop
button once or twice on vehicles with
KEYLESS-GO
R if an adult is seated properly on the front-
passenger seat and the OCS classifies the
occupant as an adult
The PASSENGER AIR BAG OFF indicator lamp
goes out again after approximately
6 seconds.
If the seat is not occupied and the OCS
detects that the front-passenger seat is
empty, the PASSENGER AIR BAG OFF
indicator lamp will continue to light up. The
PASSENGER AIR BAG OFF indicator lamp will
not go out.
For more information about the OCS, see
"Problems with the Occupant Classification
System" (Y page 56). Occupant safety
55Safety Z
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Problems with the occupant classification system
G
WARNING
If the 4 PASSENGER AIR BAG OFF indicator lamp illuminates and remains illuminated when
the weight of a typical adult or an individual that is the size of a typical adult has been detected
on the front-passenger seat, do not allow any occupant to use the front-passenger seat until the
system has been repaired. G
WARNING
If the 4 PASSENGER AIR BAG OFF 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. Problem Possible causes/consequences and
M MSolutions The PASSENGER AIR
BAG OFF indicator
lights up and remains
on.
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.
X
Have the OCS checked as soon as possible at a qualified
specialist workshop.
X Observe the additional display messages in the multifunction
display (Y page 170). Problem Possible causes/consequences and
M MSolutions The PASSENGER AIR
BAG OFF indicator
lamp does not light up
and/or stays on.
The front-passenger
seat is:
R unoccupied
R occupied with the
weight of a child up
to twelve months old
in a child restraint
system The OCS is malfunctioning.
X
Make sure there is nothing between the seat cushion and the
child seat.
X Check the installation of the child restraint system.
X Make sure that no objects are applying additional weight onto
the seat.
X If the PASSENGER AIR BAG OFF indicator lamp remains off, have
the OCS system checked as soon as possible at a qualified
specialist workshop. Do not transport a child on the front-
passenger seat until the OCS has been repaired.
X Observe the additional display messages in the multifunction
display (Y page 170). 56
Occupant safetySafety
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PRE-SAFE
®
(anticipatory occupant
protection system)
Introduction PRE-SAFE
®
takes preemptive measures to
protect occupants in certain hazardous
situations.
Important safety notes !
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.
Despite your vehicle being equipped with the
PRE-SAFE ®
system, the possibility of
personal injuries occurring as a result of an
accident cannot be eliminated.
Always adapt your driving style to suit the
prevailing road and weather conditions and
maintain a safe distance from the vehicle in
front. Drive carefully.
Function PRE-SAFE
®
intervenes:
R in emergency braking situations, e.g. when
BAS is activated.
R in critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely.
R on vehicles with DISTRONIC PLUS: if
BAS PLUS brakes hard or the radar sensor
system detects an imminent danger of
collision in certain situations.
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the seat belts are pre-tensioned.
R if the vehicle skids, the side windows are
closed so that only a small gap remains. R
the front-passenger seat is adjusted if it is
in an unfavorable position.
R Vehicles with a multicontour seat or
active multicontour seat: the air
pressure in the side bolsters is increased.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. 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.
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. More
information about seat-belt adjustment can
be found under "Seat-belt adjustment"
(Y page 60). NECK-PRO head restraints
Important safety notes G
WARNING
Do not secure any objects (e.g. coat hangers)
on the NECK-PRO head restraints. Otherwise,
the NECK-PRO head restraints may not
function properly, or in the event of a rear-end
collision may not be able offer the level of
protection they are designed to provide. G
WARNING
Seat or head restraint covers can cause a
malfunction when the NECK-PRO head
restraints are activated or when the side
impact air bags are deployed, or they can
prevent this completely. The NECK-PRO head
restraints or side impact air bags can
therefore not provide the intended protection.
Do not use any seat or head restraint covers. G
WARNING
For your protection, drive only with properly
positioned head restraints. Occupant safety
57Safety
Z
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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. G
WARNING
For safety reasons, have the NECK-PRO head
restraints checked at a qualified specialist
workshop after a rear-end collision.
The NECK-PRO head restraints reduce the
likelihood of head and chest injuries. The
NECK-PRO head restraints on the driver's and
front-passenger seats are moved forwards
and upwards in the event of a rear-end
collision of a certain severity. This provides
better head support.
If the NECK-PRO head restraints have been
triggered in an accident, reset the NECK-PRO
head restraints on the driver’s and front-
passenger seat (Y page 58). Otherwise, the
additional protection will not be available in
the event of another rear-end collision. You
can recognize when NECK-PRO head
restraints have been triggered by the fact that
they have moved forwards and can no longer
be adjusted.
Resetting triggered NECK-PRO head
restraints G
WARNING
When pushing back the NECK-PRO head
restraint cushion, make sure your fingers do
not become caught between the head
restraint cushion and the cover. Failure to
observe this could result in injuries. X
Tilt the top of the NECK-PRO head restraint
cushion forwards in the direction of
arrow :.
X Push the NECK-PRO head restraint cushion
down in the direction of arrow ;as far as
it will go.
X Firmly push the NECK-PRO head restraint
cushion back in the direction of arrow =
until the cushion engages.
X Repeat this procedure for the second
NECK-PRO head restraint.
i Resetting the NECK-PRO head restraints
requires a lot of strength. If you have
difficulty resetting the NECK-PRO head
restraints, have this work carried out at a
qualified specialist workshop. 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. 58
Occupant safetySafety
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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 62) for further information on
infants and children traveling in the vehicle
as well as on child restraint systems.
Proper 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, knee bags, front-
passenger front air bag, side impact air
bags, head air bags), Emergency
Tensioning Devices (ETDs) and seat belt
force limiters. The system is designed to
enhance the protection offered to properly
belted occupants in certain frontal (front air
bags, knee bags and ETDs) and side (side
impact air bags, head air bags and ETDs)
impacts which exceed preset deployment
thresholds.
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).
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 Occupant safety
59Safety
Z
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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 X
Adjust the seat and move the backrest to
an almost vertical position (Y page 100).
X Pull the seat belt smoothly through seat
belt 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 60).
X If necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
The seat belt on the front-passenger side is
equipped with a special seat belt retractor to
secure a child restraint system properly to the
front-passenger seat. Further information on
the "Special seat belt retractor"
(Y page 66).
Information on releasing the seat belt with
release button ?(Ypage 61).
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 161).60
Occupant safetySafety
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The seat belt adjustment is a convenience
function integrated in PRE-SAFE ®
(preventative occupant protection). More
information on PRE-SAFE ®
(Y page 57).
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. X
Press release button ?on belt buckle =.
X Guide belt tongue ;back to seat belt
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 üseat 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.
If after six seconds, the driver or front
passenger have not fastened their seat belts
and the doors are closed:
R
the ü 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
ü 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 üseat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the üseat
belt warning lamp flashes again if the vehicle
speed again exceeds 15 mph (25 km/h).
The ü 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 üseat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" (Y page 176). Occupant safety
61Safety Z
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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 co-driver's seat is unoccupied, do
not insert the belt tongue into the buckle of
the co-driver's seat. This may otherwise
lead to the triggering of the Emergency
Tensioning Device in the event of an
accident, which will then need to be
replaced.
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 seat belts 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 "( Ypage 45)
R the belt tongue is engaged in the buckle on
each of the three-point 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
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.
When triggered, seat belt force limiters help
to reduce the force exerted by the seat belt
on the vehicle occupant.
The seat 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. Child restraint systems
Important safety notes
G
WARNING
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 system must be
correctly secured using the vehicle's seat belt
in complete accordance with the child seat
manufacturer's instructions. 62
Child restraint systemsSafety