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75 Safety and Security
Self-test Occupant Classification
After turning the SmartKey in the starter
switch to position1 or2, the
75 indicator lamp located in
the center console illuminates. If an adult
occupant is properly sitting on the passen-
ger seat and the system senses the occu-
pant as being an adult, the 75
indicator lamp will illuminate and go out
after approximately 6 seconds.
If the seat is not occupied and the system
senses the passenger seat as being empty,
the 75 indicator lamp will
illuminate and not go out. More information can be found in the
“Practical hints” section (
If the 1indicator lamp and the
75indicator lamp are lit at the
same time, there is a malfunction in the
Occupant Classification System. The pas-
senger front air bag will be deactivated in
In order to ensure proper operation of the
air bag system and OCS:
Have the system checked as soon as
possible by qualified technicians.
Contact an authorized Mercedes-Benz
Sit properly belted in a position that is
as upright as possible with your back
against the seat backrest.
Do not lean on the armrests or lift your-
self from the seat by using the handle
over the door as this may cause the OCS
to be unable to correctly approximate
the occupant weight category.
Only have the seat repaired or replaced
by an authorized Mercedes-Benz
Read and observe all warnings in this
If the 75 indicator lamp should
not illuminate, the system is not functioning.
You must contact an authorized
Mercedes-Benz Center before seating any
child on the passenger seat.
Never place anything between seat
cushion and child seat (e.g. pillow), since it
reduces the effectiveness of the Occupant
Classification System. The bottom of the
child seat must make full contact with the
passenger seat cushion. 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 seats.
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76 Safety and Security
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 whenever the vehicle is in
For information on fastening seat belts,
see “Fastening the seat belts” (
iFor information on infants and children
traveling with you in the vehicle and restraint
systems for infants and children, see “Children
in the vehicle” (
Always fasten your seat belt before driving
off. Always make sure your passenger is
Failure to wear and properly fasten and
position your seat belt greatly increases
your risk of injuries and their likely severity
in an accident. You and your passenger
should always wear seat belts.
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
In the same crash, the possibility of injury or
death is lessened if you are properly wearing
your seat belt. Air bags can only protect as
they are designed if the occupants are
properly wearing their seat belts.
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position
as this can be dangerous. You could slide
under the seat belt in a collision. If you slide
under it, the seat belt would apply force at
the abdomen or neck. This could cause seri-
ous or even fatal injuries. The seat backrest
and seat belt provide the best restraint
when the wearer is in a position that is as
upright as possible and the seat belt is prop-
erly positioned on the body.
Never let more people ride in the vehicle
than there are seat belts available. Be sure
everyone riding in the vehicle is correctly
restrained with a separate seat belt. Never
use a seat belt for more than one person at
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77 Safety and Security
Damaged seat belts or seat belts that were
highly stressed in an accident must be re-
placed and their anchoring points must also
Only use seat belts which have been
approved by Mercedes-Benz.
Do not make any modifications to the seat
belts. This can lead to unintended activation
of the ETDs or to their failure to activate
Do not bleach or dye seat belts as this may
severely weaken them. In a crash, they may
not be able to provide adequate protection.
Have all work carried out only by qualified
technicians. Contact an authorized
USE SEAT BELTS PROPERLY
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 case of an accident.
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, includ-
ing rollovers. The integrated restraint
system includes SRS (driver air bag,
knee bags, passenger front air bag,
head-thorax air bags) and ETD (seat belt
emergency tensioning device). The
system is designed to enhance the
protection offered to properly belted
occupants in certain frontal (front air
bags, knee bags and ETD) and side
(head-thorax air bags and ETD) impacts
which exceed preset deployment
Never wear the shoulder belt under your
arm, against your neck or off your shoul-
der. In a frontal crash, your body would
move too far forward. That would
increase the chance of head and neck
injuries. The belt would also apply too
much force to the ribs or abdomen,
which could severely injure internal
organs such as your liver or spleen.
Never wear sear belts over rigid or
breakable objects in or on your clothing,
such as eyeglasses, pens, keys, etc., as
these might cause injuries.
Position the lap belt as low as possible
on your hips and not across the abdo-
men. If the belt is positioned across your
abdomen, it could cause serious injuries
in a crash.
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.
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78 Safety and Security
Enhanced seat belt reminder system
When the engine is started, the seat belt
telltale< will always illuminate
for 6 seconds to remind you and your
passenger to fasten your seat belts.
If the driver’s seat belt is not fastened
when the engine is started, an additional
warning chime will also sound for a maxi-
mum of 6 seconds or until the driver’s seat
belt is fastened.
If after these 6 seconds, the driver’s or the
passenger’s seat belt (with the passenger
seat occupied) are not fastened with both
the seat belt telltale< remains illu-
minated for as long as either the driv-
er’s or passenger’s seat belt is not
and if the vehicle speed once exceeds
15 mph (25 km/h), the seat belt
telltale< starts flashing and a
warning chime sounds with increasing intensity for a maximum of 60 seconds
or until both the driver’s and
passenger’s seat belt are fastened.
If the driver’s or the passenger’s seat
belt remains unfastened after
60 seconds, the warning chime stops
sounding. The seat belt telltale<
stops flashing but continues to be
The seat belt telltale< will only go out
if both the driver’s and the passenger’s
seat belt (with the passenger seat occu-
pied) are fastened, or the vehicle is stand-
ing still and a door is opened.
For more information, see the “Practical
hints” section (
Seat belts should not be worn twisted.
In a crash, you would not have the full
width of the seat belt to manage impact
forces. The twisted seat belt against
your body could cause injuries.
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.
Never place your feet on the instrument
panel, dashboard or on the seat. Always
keep both feet on the floor in front of the
When using a seat belt to secure infant
or toddler restraints or children in
booster seats, always follow the child
seat manufacturer’s instructions.
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79 Safety and Security
Emergency tensioning device (ETD),
seat belt force limiter
The seat belts are equipped with
emergency tensioning devices and seat
belt force limiters.
The ETD is designed to activate in the
in frontal or rear-end impacts exceed-
ing the system deployment threshold
if the restraint systems are operational
and functioning correctly, see
1indicator lamp (
in certain vehicle rollovers if the sys-
tem determines an additional degree of
protectionWhen activated, emergency tensioning
devices remove slack from the seat belts in
such a way that the seat belts fit more
snugly against the body. Seat belt force
limiters reduce the force exerted by the
seat belts on occupants during a crash.
Children in the vehicle
If an infant or child is traveling with you in
Secure the child using an infant or child
restraint appropriate to the age and
size of the child.
Make sure the infant or child is
properly secured at all times while the
vehicle is in motion.
iThe ETDs will only activate if the seat belts
are fastened (latch plate properly inserted into
An emergency tensioning device (ETD) that
was activated must be replaced.
When disposing of the emergency tension-
ing device, our safety instructions must be
followed. These are available at your
authorized Mercedes-Benz Center.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system. The children could
injure themselves on parts of the vehicle
be seriously or fatally injured through
excessive exposure to extreme heat or