2014 MERCEDES-BENZ M-Class seats

Occupant Classification System
(OCS)
Method of operation G
WARNING
If the 001A001C indicator lamp illuminates
when an adult or someone larger than a small
individual is in the fron tpassenger seat, have
the fron tpassenger reposition himself or
herself in the seat until the 001A001C
indicator lamp goes out.
In the event of a collision, the air bag control
unit will no tallow front passenger front air bag
deploymen twhen the OCS has classified the
front passenger seat occupant as weighing as
much as or less than a typical 12-month-old
child in a standard child restraint or if the front
passenger seat is classified as being empty.
When the OCS senses that the front
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month-old child in a standard child
restraint, the 001A001Cindicator lamp will
illuminate when the engine is started and
remain illuminated. This indicates that the
front passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat is classified as being empty,
the 001A001C indicator lamp will illuminate
when the engine is started and remain
illuminated. This indicates that the front
passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat occupant is classified as
being heavier than the weight of a typical 12-
month-old child seated in astandard child
restraint or as being a small individual (such
as a young teenager or asmall adult), the
001A001C indicator lamp will illuminate for
approximately 6seconds when the engine is
started. Depending on occupant weight
sensor readings from the seat, it will then
remain illuminated or go out. With the
001A001C indicator lamp illuminated, the
fron tpassenger fron tair bag is deactivated. With the
001A001C indicator lamp out, the
front passenger front air bag is activated.
When the OCS senses that the front
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 001A001Cindicator lamp will
illuminate for approximately six seconds
when the engine is started and the ngo out.
This indicates that the front passenger front
air bag is activated.
If the 001A001C indicator lamp is illuminated,
the front passenger front air bag is
deactivated and will not be deployed.
If the 001A001C indicator lamp is not
illuminated, the front passenger front air bag
is activated and will be deployed
R in the event of certain frontal impacts
R if the impact exceeds a predetermined
triggering threshold
R independent of the side impact air bag or
pelvis air bag
If the front passenger front air bag is
deployed, the rate of inflation will be
influenced by
R the rate of vehicle deceleration as assessed
by the air bag control unit
R the front passenger's weight category as
identified by the OCS 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
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 Occupant safety
49Safety
Z

Problem Possible causes/consequences and
0001 Solutions
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 Make sure that the backrest and base of the child restraint
system are resting securely on the front-passenger seat. If
necessary, adjust the position of the front-passenger seat.
X When installing the child restraint system, make sure that the
seat belt is tight. Do not pull the seat belt tight with the front-
passenger seat adjustment .This could result in the seat belt
being pulled too tightly.
X Check the installation of the child restraint system.
X Make sure that no objectsa re 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 293). 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 intervenes powerfully or the
radar sensor system detect sanimminent
dange rofcollision in certain situations.
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
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. 54
Occupant safetySafety

R
on vehicles with the memory function:
the front-passenger seat is adjusted if it is
in an unfavorable position.
R vehicles with amulticontour seat: the
airp ressure in the side bolsters of the
backrest is increased.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the beltp re-tensioning. On vehicles with
multicontour seats, the air pressure in the
side bolsters 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 beltp re-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 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
yourj ourney. 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 Canadia nprovinces
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.
Correct use of the seat belts G
WARNING
USE SEAT BELTS PROPERLY
R Seat belts can only work when used
properly.N ever wear seat belts in any other
way than as described in this section, as Occupant safety
55Safety
Z

tha
tcould 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, 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.N ever 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 distribut eimpact forces.
The twisted seat belt against yourb ody
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. G
WARNING
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. 56
Occupant safetySafety

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
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.
Ac hild'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. X
Adjust the seat and move the backrest to
an almost vertical position (Y page 104).
X Pull the seat belt smoothly through belt
sash guide 0002.
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 0003in buckle 0023.
Seat-belt adjustment:ifn ecessary, 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 except the driver's seat belt are
equipped with a special seat belt retractor to
securely fasten child restraint systems in the
vehicle. Further information can be found
under "Special seat belt retractor"
(Y page 63).
For more information about releasing the seat
belt with release button 0022, see "Releasing
seat belts" (Y page 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 277).
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

Belt height adjustment
You can adjus
tthe seat belt height on the
front 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 0002.
X Slide the belt sash guide downwards.
X Release belt sash guide release 0002and
make sure that the belt sash guide has
engaged.
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. 0002
Belt sash guide
0003 Seat belt tongue
0023 Buckle
0022 Release button
X Press release button 0022and guide belt
tongue 0003back towards belt sash
guide 0002.
Belt warning for the driver and front
passenger Every time the engine is started, the
0020
seat belt warning lamp lights up for six
seconds. It lights up regardless of whether
the driver's and front-passenger seat belts
have already been fastened. If the driver's
and front-passenger seat belts have already
been fastened, the 0020seat belt warning
lamp then goes out.
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 0020 seat belt warning lamp remains lit
as long as the driver's or front-passenger's
seat belt is not fastened 58
Occupant safetySafety

and
R if a vehicle speed of 15 mph (25 km/h) is
exceeded, the 0020seat belt warning lamp
begins to flash. Awarning 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
0020 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases eve nifthe driver or
front-passenger seat belt has still not been
fastened after 60 seconds. The 0020seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated. The 0020seat
belt warning lamp flashes again if the vehicle
speed exceeds 15 mph (25 km/h).
The 0020 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 0020seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" (Y page 317).
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 Emergency Tensioning Devices on the
driver's and front-passenger seat consist of
pyrotechnic belt buckle tensioners and belt
anchor installation tensioners that are
triggered together. The belt buckle tensioner
is mounted on the B-pillar and the belt anchor
installation is mounted on the side of the seat.
After deploying, both tensioners must always
be replaced.
Emergency Tensioning Devices tighten the
seat belts in an accident, pulling them close
against the body.
Emergency Tensioning Devices do not
correct incorrect seat positions or incorrectly
fastened seat belts.
Emergency Tensioning Devices do not pull
vehicle occupants back towards the
backrest.
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 for the front seats
are synchronized with the front air bags,
which take on a part of the deceleration force.
This results in the force exerted on the
occupant being distributed over a greater
area. Occupant safety
59Safety Z

Emergency Tensioning Devices can only be
activated when:
R
the ignition is switched on.
R the restraint systems ar eoperational; see
"SRS warning lamp" (Y page 43)
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 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 if, in the event of a head-on or rear-end
collision, the vehicle decelerates or
accelerates rapidly in a longitudinal
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 situation swhere the vehicle
rolls over, 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 001FSRS
warning lamp lights up. 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 001A001Cindicator
lamp is illuminated, indicating that the front
passenger front air bag is deactivated. 60
Children in the vehicleSafety