MERCEDES-BENZ SLK280 2008 R171 Manual PDF

70 Safety and Security
Occupant safety
The air bags will not deploy in impacts
which do not exceed the system’s deploy-
ment thresholds. You will then be protect-
ed by the fastened seat belts.The passenger air bag will only be de-
ployed if

the system, based on OCS weight sen-
sor readings, senses that the front pas-
senger seat is occupied

the 75indicator lamp in
the center console is not lit
(
page 74)

the impact exceeds a preset deploy-
ment threshold
Knee bags
The driver-side knee bag is located on the
driver’s side lower instrument panel. The
passenger-side knee bag is located on the
passenger side below the glove box. They
are designed to operate together with the
front air bags in certain frontal impacts
exceeding a preset threshold. The knee
bags operate best in conjunction with
properly positioned and fastened seat
belts.Head-thorax air bags
1Head-thorax air bag
The head-thorax air bags are deployed

in impacts exceeding a preset deploy-
ment threshold

on the impacted side of the vehicle

independently of the front air bags
The head-thorax air bags are not deployed
in impacts which do not exceed the
system’s deployment threshold.
iThe front air bags in this vehicle have been
designed to inflate in two stages. This allows
the air bag to have different rates of inflation that
are based on the rate of relevant vehicle deceler-
ation as assessed by the air bag control unit.
On the passenger side, the front air bag
deployment is additionally influenced by the
passenger’s weight category as identified by the
Occupant Classification System (OCS)
(
page 71).
The lighter the passenger side occupant, the
higher the vehicle deceleration rate required for
the second stage inflation of the air bag.

71 Safety and Security
Occupant safety
Occupant Classification System
The O
ccupant Classification System (OCS)
automatically turns the passenger front air
bag and passenger-side knee bag on or off
based on the classified occupant weight
category determined by weight sensor
readings from the passenger seat.
Occupants must sit properly belted in a
position that is as upright as possible with
their back against the seat backrest and
feet on the floor to be correctly classified.
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. Both driver and the passenger should al-
ways use the 75 indicator
lamp as an indication of whether or not the
passenger is properly positioned
(
page 76).
Warning!G
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 deploy-
ment of the head-thorax air bags. Contact
an authorized Mercedes-Benz Center for
availability.
iThe system does not deactivate the
head-thorax air bag and the emergency tension-
ing device.
iIf the 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.

72 Safety and Security
Occupant safety
Warning!G
If the 75 indicator lamp illumi-
nates when an adult or someone larger than
a small individual is in the passenger seat,
have the passenger re-position himself or
herself in the seat until the 75
indicator lamp goes out.
More information about air bag display
messages (
page 365).
In the event of a collision, the air bag control
unit will not allow passenger front air bag
deployment when the OCS classified the
passenger seat occupant as being up to or
less than the weight of a typical
12-month-old child in a standard child
restraint or if the passenger seat is sensed
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 75 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
75 indicator lamp will illumi-
nate 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
75 indicator lamp will illumi-
nate for approximately 6 seconds when the
engine is started and then, depending on
occupant weight sensor readings from the
seat, remain illuminated or go out. With the
75 indicator lamp illuminated,
the passenger front air bag is deactivated.
With the 75 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
75 indicator lamp will illumi-
nate for approximately 6 seconds when the
engine is started and then go out, indicating
that the passenger front air bag is activated.

73 Safety and Security
Occupant safety
If the 75 indicator lamp is
illuminated, the passenger front air bag is
deactivated and will not be deployed.
If the 75 indicator lamp is not
illuminated, the passenger front air bag is
activated and will be deployed:

in the event of certain frontal impacts

if impact exceeds a preset deployment
threshold

independently of the head-thorax air
bags
If the passenger front air bag is deployed,
the rate of inflation will be influenced by:

the rate of relevant vehicle deceleration
as assessed by the air bag control unit

passenger’s weight category as identi-
fied by the Occupant Classification
System (OCS)
Warning!G
Children 12 years old and under must be
seated and properly secured in an appropri-
ate infant or child restraint 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 manufactur-
er's instructions.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information:

Your vehicle is equipped with air bag
technology designed to turn off the pas-
senger front air bag in your vehicle when
the system senses the weight of a typi-
cal 12-month-old child or less along with
the weight of a standard appropriate
child restraint on the passenger seat.

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 in-
stalled in your vehicle.

If you install a rear-facing child restraint
on the passenger seat, make sure that
the 75indicator lamp is
illuminated, indicating that the passen-
ger front air bag is deactivated. Should
the 75 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check the 75
indicator lamp while driving to make
sure the 75 indicator lamp
is illuminated. If the 75 in-
dicator 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 in-
jured or even killed if the passenger
front air bag inflates.


74 Safety and Security
Occupant safety
The 75indicator lamp is
located in the center console.
1Passenger front air bag off indicator
lamp
The 75indicator lamp1 will
be illuminated, except with the SmartKey
removed or in starter switch position0.
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 recom-
mended 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.
For children larger than the typical
12-month-old child, the passenger front
air bag may or may not be activated
(
page 72).
iDeployment of the driver front air bag does
not mean that the passenger front air bag also
should have deployed.
The Occupant Classification System (
page 71)
may have determined:

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 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.

that the seat was occupied by a small individ-
ual (such as a young teenager or a small
adult) or a child weighing more than the
weight of a typical 12-month-old child in a
standard child restraint – 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.


75 Safety and Security
Occupant safety
Self-test Occupant Classification
System
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 (
page 358).
Warning!G
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
this case. Have the system checked as soon
as possible by qualified technicians. Contact
an authorized Mercedes-Benz Center.
Only have the seat repaired or replaced by
an authorized Mercedes-Benz Center.
In order to ensure proper operation of the
air bag system and OCS:

Sit properly belted in a position that is
as upright as possible with your back
against the seat backrest.

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 to be unable to correctly
approximate the occupant’s weight
category.

Read and observe all warnings in this
chapter.Warning!G
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.
Warning!G
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.

76 Safety and Security
Occupant safety
Seat belts
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.
For information on fastening seat belts,
see “Fastening the seat belts” (
page 48).
iFor information on infants and children
traveling with you in the vehicle and restraint
systems for infants and children, see “Children
in the vehicle” (
page 79).
Warning!G
Always fasten your seat belt before driving
off. Always make sure your passenger is
properly restrained.
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
or killed.
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.
Warning!G
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.
Warning!G
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
a time.

77 Safety and Security
Occupant safety
Warning!G
Damaged seat belts or seat belts that were
highly stressed in an accident must be re-
placed and their anchoring points must also
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.
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.
Warning!G
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
thresholds.

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.


78 Safety and Security
Occupant safety
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
doors closed,

the seat belt telltale< remains illu-
minated for as long as either the driv-
er’s or passenger’s seat belt is not
fastened.

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
illuminated.
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 (
page 353).

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
seat.

When using a seat belt to secure infant
or toddler restraints or children in
booster seats, always follow the child
seat manufacturer’s instructions.


79 Safety and Security
Occupant safety
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
following cases:

in frontal or rear-end impacts exceed-
ing the system deployment threshold

if the restraint systems are operational
and functioning correctly, see
1indicator lamp (
page 64)

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
the vehicle:
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
buckle).
Warning!G
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 any
authorized Mercedes-Benz Center.
Warning!G
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
cold