2011 MERCEDES-BENZ SLK300 ECU

R
independently of the front air bags
R independently of the ETDs
The passenger head-thorax air bag : will
only deploy if the OCS senses that the
passenger seat is occupied and the impact
exceeds a preset deployment threshold.
Head-thorax air bags : are not deployed in
side impacts which do not exceed the
system’s deployment threshold. G
Warning!
Only use seat covers which have been tested
and approved by Mercedes-Benz for your
vehicle model. Using other seat covers may
interfere with or prevent the deployment of
the head-thorax air bags. Contact an
authorized Mercedes-Benz Center for
availability. Occupant Classification System
The Occupant Classification System (OCS)
activates or deactivates the passenger front
air bag and passenger-side knee bag
automatically.
The respective status is based
on the classified occupant weight category
determined by weight sensor readings from
the passenger seat.
The system does not deactivate the
passenger head-thorax air bag and the
Emergency Tensioning Devices (ETDs).
To be classified correctly, the passenger must
sit
R with the seat belt properly fastened
R in a position that is as upright as possible
with the back against the seat backrest
R with the feet on the floor
If the occupant’s weight is transferred to
another object in the vehicle (e.g. by leaning
on armrests), the OCS may not be able to
properly approximate the occupant’s weight
category.
If your seat, including the trim cover and
cushion, needs to be serviced in any way, take the vehicle to an authorized Mercedes-Benz
Center.
Only seat accessories approved by
Mercedes-Benz may be used.
Both the driver and the passenger should
always use the
04 indicator
lamp as an indication of whether or not the
passenger is properly positioned. G
Warning!
If the 04 indicator lamp
illuminates when an adult or someone larger
than a small individual is in the passenger
seat, have the passenger reposition himself
or herself in the seat until the
04 indicator lamp goes out.
In the event of a collision, the air bag control
unit will not allow passenger front air bag
deployment when the OCS has classified the
passenger seat occupant as weighting as
much as or less than a typical 12-month-old
child in a standard child restraint or if the
passenger seat is classified as being empty.
When

the OCS senses that the 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
04 indicator lamp will illuminate
when the engine is started and remain
illuminated, indicating that the passenger
front air bag is deactivated.
When the OCS senses that the passenger seat
is classified as being empty, the
04 indicator lamp will illuminate
when the engine is started and remain
illuminated, indicating that the passenger
front air bag is deactivated.
When the OCS senses that the passenger seat
occupant is classified as being heavier than
the weight of a typical 12-month-old child
seated in a standard child restraint or as being
a small individual (such as a young teenager
or a small adult), the 04
indicator lamp will illuminate for
approximately 6 seconds when the engine is
started and then, depending on occupant Occupant safety
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weight sensor readings from the seat, remain
illuminated or go out. With the
04 indicator lamp illuminated,
the passenger front air bag is deactivated.
With the 04 indicator lamp out,
the passenger front air bag is activated.
When
the OCS senses that the passenger seat
occupant is classified as an adult or someone
larger than a small individual, the
04 indicator lamp will illuminate
for approximately 6 seconds when the engine
is started and then go out, indicating that the
passenger front air bag is activated.
If the 04 indicator lamp is
illuminated, the passenger front air bag is
deactivated and will not be deployed.
If the 04 indicator lamp is not
illuminated, the passenger front air bag is
activated and will be deployed
R in the event of certain frontal impacts
R if impact exceeds a preset deployment
threshold
R independently of the head-thorax air bag
If the passenger front air bag is deployed, the
rate of inflation will be influenced by
R the rate of relevant vehicle deceleration as
assessed by the air bag control unit
R the passenger’s weight category as
identified by the OCS
For more information on air bag display
messages in the multifunction display, see
(Y page 239). 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 must be properly
secured with the vehicle’s seat belt 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:
R Your vehicle is equipped with air bag
technology designed to deactivate the
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 passenger seat.
R A child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the passenger front air bag
inflates in a collision which could occur
under some circumstances, even with the
air bag technology installed in your vehicle.
R If you install a rear-facing child restraint on
the passenger seat, make sure the
04 indicator lamp is
illuminated, indicating that the passenger
front air bag is deactivated. Should the
04 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check the 04
indicator lamp while driving to make sure
the 04 indicator lamp is
illuminated. If the 04 indicator
lamp goes out or remains out, do not
transport a child on the passenger seat
until the system has been repaired.
A child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the passenger front air bag
inflates.
R If you place a child in a forward-facing child
restraint on the passenger seat, move the
seat as far back as possible, use the proper
child restraint recommended for the age, 38
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size and weight of the child, and secure
child restraint with the vehicle’s seat belt
according to the child seat manufacturer’s
instructions. For children larger than the
typical 12-month-old child, the passenger
front air bag may or may not be activated.
Deployment of the driver front air bag does
not mean that the passenger front air bag also
should have deployed.
The OCS may have determined
R that the seat was empty or occupied by the
weight up to or less than that of a typical
12-month-old child seated in a standard
child restraint – both of which are instances
where the system suppresses deployment
of the passenger front air bag even though
the impact met the criteria and was of
sufficient severity to deploy the driver front
air bag
R that the seat was occupied by a small
individual (such as a young teenager or a
small adult) or a child who weighs more
than the weight of a typical 12-month-old
child in a standard child restraint – both of
which are instances where the system may
suppress deployment of the passenger
front air bag even though the impact met
the criteria and was of sufficient severity to
deploy the driver front air bag 04 indicator lamp
: will be
illuminated, except with the SmartKey
removed from the starter switch or with the
starter switch in position 0. G
Warning!
If the red SRS indicator lamp + in the
instrument cluster and the 04
indicator lamp are lit at the same time, there
is a malfunction in the OCS. The passenger
front air bag will be deactivated in this case.
Have the system checked by qualified
technicians as soon as possible. Contact an
authorized Mercedes-Benz Center.
Only have the seat repaired or replaced at an
authorized Mercedes-Benz Center.
In order to ensure proper operation of the air
bag system and OCS:
R Sit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
R While seated, an occupant should not
position him/herself in such a way as to
cause the occupant’s weight to be lifted
from the seat bottom as this may result in
the OCS being unable to correctly
approximate the occupant’s weight
category.
R Read and observe all warnings in this
chapter.
OCS Self-test After turning the SmartKey in the starter
switch to position 1 or 2 the
04 indicator lamp illuminates. If
an adult occupant is properly sitting on the
passenger seat and the system classifies the
occupant as an adult, the
04
indicator lamp will illuminate and go out after
approximately 6 seconds.
If the seat is not occupied and the system
classifies the passenger seat as being empty,
the 04 indicator lamp will
illuminate and not go out. G
Warning!
If the 04 indicator lamp does not
illuminate, the system is not functioning. You
must contact an authorized Mercedes-Benz Occupant safety
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Center before seating any child on the
passenger seat.
For more information, see the “Practical
hints” section ( Y page 263). G
Warning!
Never place anything between seat cushion
and child seat (e.g. pillow), since it reduces
the
effectiveness of the OCS. The bottom and
back of the child seat must make full contact
with the passenger seat cushion and
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 seats. Seat belts
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 whenever the vehicle is in motion.
i
See “Children in the vehicle”
(Y page 45) for information on
R infants

and children traveling with you in
the vehicle
R restraint systems for infants and children G
Warning!
Always fasten your seat belt before driving off.
Always
make sure your passenger is properly
restrained. You and your passenger 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. G
Warning!
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. That could cause serious
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 properly
positioned on the body. G
Warning!
Never let more people ride in the vehicle than
there are seat belts available. Make 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 a
time. G
Warning!
Damaged seat belts or seat belts that have
been
subjected to stress in an accident must
be replaced. Also, the seat belt anchoring
points must be checked.
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 when
necessary. 40
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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
Mercedes-Benz Center.
Proper use of seat belts G
Warning!
USE SEAT BELTS PROPERLY
R Seat belts can only protect 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.
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,
passenger front air bag, head-thorax 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 (head-thorax
air bags and ETDs) impacts which exceed
preset deployment thresholds.
R Never wear the shoulder belt under your
arm, against 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. 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. G
Warning!
Do not pass seat belts over sharp edges. They
could tear. Occupant safety
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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 the seat belts G
Warning!
Children 12 years old and under must be
seated and properly secured in an
appropriately sized infant restraint, toddler
restraint, or booster seat recommended for
the size and weight of the child. For additional
information, see section “Children in the
vehicle”.
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. X
With a smooth motion, pull the seat belt out
of the seat belt outlet.
Loop : guides the seat belt.
X Place the shoulder portion of the seat belt
across the top of your shoulder and the lap
portion across your hips. X
Push latch plate ; into buckle = until it
clicks.
X If necessary, tighten the lap portion to a
snug fit by pulling shoulder portion up.
The passenger lap/shoulder belt has a
special seat belt retractor to secure child
restraints properly. For more information on
special seat belt retractors, see “Infant and
child restraint systems” (Y page 45).
To release the seat belt with seat belt release
button ?, see ( Y page 42).
Releasing the seat belts X
Press seat belt release button ?
(Y page 42).
Allow the retractor to completely rewind
the seat belt by guiding latch plate ;
(Y page 42).
! Make sure the seat belt retracts
completely. Otherwise the seat belt and/or
latch plate could get caught or pinched in
the door or in the seat mechanism. This can
damage the seat belt and impair its
effectiveness, and/or cause damage to the
door and/or door trim panel. Such damage
is not covered by the Mercedes-Benz
Limited Warranty.
Damaged seat belts must be replaced.
Contact an authorized Mercedes-Benz
Center.
Enhanced seat belt reminder system When the engine is started, the seat belt
telltale
7 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 sound. The warning chime goes out
after approximately 6 seconds or once the
driver’s seat belt is fastened. 42
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If after these 6 seconds the driver’s or the
passenger’s seat belt (with the passenger
seat occupied) is not fastened with both
doors closed,
R
the seat belt telltale 7 remains
illuminated
for as long as either the driver’s
or passenger’s seat belt is not fastened.
R and if the vehicle speed once exceeds
15 mph (25 km/h), the seat belt telltale
7 starts flashing and a warning chime
sounds with increasing intensity for a
maximum of 60 seconds or until the
driver’s and passenger’s seat belt are
fastened.
If you and/or your passenger release the
seat belt during driving, the seat belt
telltale 7 starts flashing and the
warning chime sounds as described before.
If the driver’s or the passenger’s seat belt
remains unfastened after 60 seconds, the
warning chime stops sounding, the seat
belt telltale 7 stops flashing but
continues to be illuminated.
After a vehicle standstill, the warning chime
is reactivated and the seat belt telltale
7 is flashing again if the vehicle speed
once exceeds 15 mph (25 km/h).
The seat belt telltale 7 will only go out if
both the driver’s and the passenger’s seat
belt (with the passenger seat occupied) are
fastened, or the vehicle is standing still and a
door is opened.
For more information, see “Practical hints”
(Y page 259).
Emergency Tensioning Device (ETD),
seat belt force limiter The seat belts are equipped with ETDs and
seat belt force limiters. The ETDs are designed to activate in the
following cases:
R
in frontal or rear-end impacts exceeding
the system’s preset deployment threshold
R if
the restraint systems are operational and
functioning correctly, see “SRS indicator
lamp” (Y page 32)
R in certain vehicle rollovers if the system
determines an additional degree of
protection
The ETDs will only activate if the seat belts are
fastened (latch plate properly inserted into
buckle).
In an impact, the ETDs remove slack from the
seat belts in such a way that the seat belts fit
more snugly against the body. Seat belt force
limiters, when activated, are employed to
help reduce the peak force exerted by the
seat belts on occupants during a crash.
i The ETDs do not correct an incorrect seat
position or incorrectly worn seat belts.
The ETDs do not pull occupants back
toward the seat backrest. G
Warning!
Pyrotechnic ETDs that were activated must be
replaced.
For your safety, when disposing of the
pyrotechnic ETDs always follow our safety
instructions. These are available at any
authorized Mercedes-Benz Center. Correct driver seat adjustment
G
Warning!
In order to avoid possible loss of vehicle
control
the following must be done before the
vehicle is put into motion:
R seat adjustment
R head restraint adjustment
R steering wheel adjustment Occupant safety
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R
rear view mirror adjustment
R fastening of seat belts Steering wheel
G
Observe Safety notes, see page 66.
X Position steering wheel : properly. See
(Y page 66) for manual adjustment and
(Y page 66) for electrical adjustment.
Make sure:
R You can reach the steering wheel with your
arms slightly bent at the elbows.
R You can move your legs freely.
R All displays (including malfunction and
indicator lamps) on the instrument cluster
are clearly visible.
Seat belt G
Observe Safety notes, see page 40.
X Fasten and position your seat belt ;
correctly (Y page 42). Make sure:
R
The seat belt is always fitted snugly.
R Adjust the seat belt so that the shoulder
section is located as close as possible to
the middle of the shoulder.
R Place the lap portion of the seat belt as low
as possible on your hips.
Seat and head restraint G
Observe Safety notes, see page 62.
X Position seat = and head restraint
properly. See ( Y page 63) for seat and
head restraint adjustment.
Observe the following points:
R Always be in a properly seated position.
R The position should be as far rearward from
the front air bag in the steering wheel as
possible, while still permitting proper
operation of vehicle controls.
R Adjust the seat to a comfortable seating
position that still allows you to reach the
accelerator/brake pedal safely.
R The seat must be adjusted so that you can
correctly fasten and position your seat belt.
R The seat backrest must be in a position that
is as nearly upright as possible.
R Adjust the seat cushion so that the front
edge of the seat cushion lightly supports
your legs.
R 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.
R Never place hands under the seat or near
any moving parts while the seat is being
adjusted. 44
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