MERCEDES-BENZ SLK-CLASS ROADSTER 2012 Service Manual

impact air bag and/or head bag inflates.
This could result in serious or fatal injuries
should the side impact air bag and/or head
bag be deployed. 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.
Failure to follow these instructions can result
in severe injuries to you or other occupants.
If you sell your vehicle, it is important that you
make the buyer aware of this safety
information. Be sure to give the buyer this
Operator's Manual.GWARNING
If the side impact air bag and/or head bag is
deployed in the event of a side impact and the
front passenger, especially a child, is not
properly seated or restrained when next to a
side impact air bag/head bag, injuries are
possible due to the rapid inflation of the side
impact air bag/head bag.
To help avoid the possibility of injury, please
follow these guidelines:
(1)Always sit as upright as possible,
and use the seat belts properly.
Make sure that children 12 years
old and under use an appropriately
sized child restraint, infant
restraint or booster seat
recommended for the size and
weight of the child.(2)Always wear seat belts properly.
The air bags are only deployed if the air bag
control unit detects the need for deployment.
Only in the event of such a situation will they
provide their supplemental protection.
The driver and passenger should always wear
their seat belts. Otherwise, it is not possible
for the air bags to provide their supplemental
protection.
In the event of other types of impacts and
impacts below air bag deployment
thresholds, the air bags will not deploy. The
driver and passengers will then be protected
to the extent possible by a properly fastened
seat belt. A properly fastened seat belt is also
needed to provide the best possible
protection in a rollover.
Air bags provide additional protection; they
are not, however, a substitute for seat belts.
All vehicle occupants must fasten their seat
belts regardless of whether your vehicle is
equipped with air bags or not.
It is important for your safety and that of your
passenger to have deployed air bags replaced
and to have any malfunctioning air bags
repaired. This will help to make sure the air
bags continue to perform their protective
function for the vehicle occupants in the
event of a crash.
Front air bags
The front air bags increase protection for the
driver's and front-passenger's head and
chest.
:Driver's air bag;Front-passenger front air bag=Front-passenger knee bag?Driver's knee bag
Driver's air bag : deploys in front of the
steering wheel; front-passenger front air
bag ; deploys in front of and above the glove
box.
Occupant safety39SafetyZ

They are deployed:
R in the event of certain frontal impacts
R if the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
R if the seat belt is fastened
R independently of other air bags in the
vehicle
If the vehicle overturns, the front air bags are
generally not deployed. If the system detects
high vehicle deceleration in a longitudinal
direction, the front air bags are deployed.
Your vehicle has adaptive, two-stage front air
bags. In the event of a collision, the air bag
control unit evaluates the vehicle
deceleration. In the first deployment stage,
the front air bag is filled with enough
propellant gas to reduce the risk of injuries.
The front air bag is fully deployed if a second
deployment threshold is exceeded within a
few milliseconds.
The deployment of the front-passenger front
air bag is also influenced by the weight
category of the front passenger, which is
determined by the Occupant Classification
System (OCS) ( Y page 42).
The lighter the passenger-side occupant, the
higher the vehicle deceleration rate required
(predicted at the start of the impact) for
second stage inflation of the front-passenger
front air bag. In the second stage, the front
air bags are inflated with the maximum
amount of propellant gas available.
The front air bags are not deployed in
situations where a low impact severity is
predicted. You will then be protected by the
fastened seat belt.The front-passenger front air bag will only
deploy if:
R the system, based on the OCS weight
sensor readings, detects that the front-
passenger seat is occupied.
R the ^a indicator lamp in the center
console is not lit, ( Y page 42).
R the air bag control unit predicts a high
impact severity.
Knee bagsGWARNING
Observe "Important safety notes"
( Y page 38).
Knee bags provide increased protection for
the driver and front passenger against the risk
of:
R knee injuries
R thigh injuries
R lower leg injuries
Driver's knee bag ?(Y page 39) deploys
underneath the steering column and front-
passenger knee bag =(Y page 39)
underneath the glove box. They deploy
together with the front air bags. They are
designed to operate together with the front
air bags in frontal impacts if certain
thresholds are exceeded. The knee bags
operate at best in conjunction with correctly
positioned and fastened seat belts.
Side impact air bags
GWARNING
The pressure sensors for side impact air bag
control are located in the doors. Do not
modify any components of the doors or door
trim panels including, for example, the
addition of door speakers.
Improper repair work on the doors or the
modification or addition of components to the
doors create a risk of rendering the side
impact air bags inoperative or causing
unintended air bag deployment. Work on the
40Occupant safetySafety

doors must therefore only be performed by
qualified technicians. Contact an authorized
Mercedes-Benz Center.GWARNING
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 side impact air bags. Contact an
authorized Mercedes-Benz Center for
availability.
When deployed, the side impact air bags offer
additional protection for the thorax of the
vehicle occupants on the side of the vehicle
on which the impact occurs. However, they
do not protect the:
R head
R neck
R arms
Side impact air bags : deploy next to the
outer seat cushions.
Side impact air bags : are deployed:
R on the side on which an impact occurs
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R depending on whether the seat belt is being
used
R independently of the front air bags
R independently of the ETDs
If the vehicle overturns, the side impact air
bags are generally not deployed. Exception: if
the system detects high vehicle deceleration
or acceleration in a lateral direction and
determines that deployment can offer
additional protection to that provided by the
seat belt.
Side impact air bags will not deploy in side
impacts which do not exceed the system's
preset deployment thresholds for lateral
acceleration/deceleration. You will then be
protected by the fastened seat belt.
The side impact air bag on the front-
passenger side will not deploy under the
following conditions:
R the OCS detects that the front-passenger
seat is not occupied.
R the front-passenger seat belt is not
fastened.
The side impact air bag on the front-
passenger side will deploy if the front-
passenger seat belt is fastened, regardless of
whether the front-passenger seat is occupied
or not.
Head bagsGWARNING
Observe "Important safety notes"
( Y page 38).
Head bags enhance the level of protection for
the head, but not the chest or arms, of the
vehicle occupants in the front of the vehicle
on the side on which the impact occurs.
Head bags : deploy in the area of the side
windows at the front. They are deployed:
Occupant safety41SafetyZ

Rat the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R on the side on which an impact occurs
R on the driver's side and passenger side, in
the event of a vehicle rollover and if the
system determines that air bag deployment
can offer the vehicle occupants additional
protection to that provided by the seat belt
R independently of the use of the seat belt
R independently of the front air bags
Head bags : will not deploy in side impacts
which do not exceed the system's preset
deployment thresholds for lateral
acceleration/deceleration. You will then be
protected by the fastened seat belt.
The head bag on the front-passenger side will
not deploy under the following conditions:
R the OCS detects that the front-passenger
seat is not occupied.
R the front-passenger seat belt is not
fastened.
The head bag on the front-passenger side will
deploy if the front-passenger seat belt is
fastened, regardless of whether the front-
passenger seat is occupied or not.
Occupant Classification System
(OCS)
How the Occupant Classification
System works
The Occupant Classification System (OCS)
categorizes the occupant on the front-
passenger seat using a weight sensor. The
front-passenger front air bag and the front-
passenger knee bag are deactivated
automatically for certain weight categories.
The ^a indicator lamp shows you the
current status. When the ^a indicator
lamp is illuminated, the front-passenger front
air bag and the front-passenger knee bag are
deactivated.
The system does not deactivate:
R the side impact air bag
R the front-passenger head bag
R the Emergency Tensioning Devices
To be classified correctly, the front passenger
must sit:
R with the seat belt fastened correctly
R in a position that is as upright as possible
with their back against the seat backrest
R with their feet on the floor
If the front-passenger's weight is transferred
to another object in the vehicle (e.g. by
leaning on armrests), OCS may not be able to
approximate the occupant's weight category.
If the front-passenger seat, the seat cover or
the seat cushion are damaged, have the
necessary repair work carried out at an
authorized Mercedes-Benz Center.
For safety reasons, Mercedes-Benz
recommends that you only use seat
accessories that have been approved by
Mercedes-Benz.
Both the driver and the front passenger
should always use the ^a indicator
lamp as an indication of whether or not the
front passenger is properly positioned.GWARNING
If the 4 PASSENGER AIR BAG OFF
indicator lamp illuminates when an adult or
someone larger than a small individual is in
the front-passenger seat, have the front
passenger reposition himself or herself in the
seat until the 4 PASSENGER AIR BAG OFF
indicator lamp goes out.
In the event of a collision, the air bag control
unit will not allow front-passenger front air
bag and front-passenger knee bag
deployment when the OCS has classified the
front-passenger 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
unoccupied.
42Occupant safetySafety

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 4 PASSENGER AIR BAG OFF
indicator lamp will illuminate when the engine
is started and remain illuminated. This
indicates that the front-passenger front air
bag and the front-passenger knee bag are
deactivated.
When the OCS senses that the front-
passenger seat is classified as being empty,
the 4 PASSENGER AIR BAG OFF indicator
lamp will illuminate when the engine is started
and remain illuminated. This indicates that
the front-passenger front air bag and the
front-passenger knee bag are 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 a standard child
restraint or as being a small individual (such
as a young teenager or a small adult), the
4 PASSENGER AIR BAG OFF indicator
lamp will illuminate for approximately 6
seconds when the engine is started.
Depending on occupant weight sensor
readings from the seat, it will then remain
illuminated or go out. If the 4 PASSENGER
AIR BAG OFF indicator lamp is illuminated, the
front-passenger front air bag and the front-
passenger knee bag are deactivated. If the
4 PASSENGER AIR BAG OFF indicator
lamp is not illuminated, the front-passenger
front air bag and the front-passenger knee
bag are activated.
When the OCS senses that the front-
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 4 PASSENGER AIR BAG
OFF indicator lamp will illuminate for
approximately six seconds when the engine is
started and then go out. This indicates that
the front-passenger front air bag and the
front-passenger knee bag are activated.If the 4 PASSENGER AIR BAG OFF
indicator lamp is illuminated, the front-
passenger front air bag and the front-
passenger knee bag are deactivated and are
not deployed.
If the 4 PASSENGER AIR BAG OFF
indicator lamp is not illuminated, the front-
passenger front air bag and the front-
passenger knee bag are activated and are
deployed:
R in certain front impacts
R independently of the side impact air bag
and head bag
R if the impact has exceeded a
predetermined threshold value for
deployment
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
determined by the OCS
For further information, see "Air bag display
messages" ( Y page 211).GWARNING
Children under 12 years must be secured
correctly in a suitable infant or child restraint
system or booster seat suitable 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, in particular children, must sit as
upright as possible, fasten the seat belt
correctly and use a suitable infant restraint
system, child restraint system or booster seat
suitable for the size and weight of the child.
Children can be seriously or even fatally
injured by an air bag deploying.
Occupant safety43SafetyZ

Observe the following information:
R Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger front air bag and the front-
passenger knee 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 A child in a rear-facing child restraint
system on the front-passenger seat will be
seriously injured or even killed if the front-
passenger front air bag inflates in a collision
despite the air bag technology installed in
your vehicle, which could occur under some
circumstances.
R If you must install a rearward-facing child
restraint on the front-passenger seat, make
sure the 4 PASSENGER AIR BAG OFF
indicator lamp is illuminated, indicating
that the front-passenger front air bag and
front-passenger knee bag are deactivated.
If the 4 PASSENGER AIR BAG OFF
indicator lamp does not light up or goes out
when a rearward-facing child restraint
system is installed, please check
installation. Periodically check the 4
PASSENGER AIR BAG OFF indicator lamp
while driving to make sure the 4
PASSENGER AIR BAG OFF indicator lamp is
illuminated. If the 4 PASSENGER AIR
BAG OFF indicator lamp goes out or
remains out do not carry a child on the
front-passenger seat.
R A child in a rearward-facing child restraint
system on the front-passenger seat will be
seriously injured or even killed if the front-
passenger air bag is deployed.R When securing a child in a child restraint
system on the front-passenger seat, you
must:
- move the front-passenger seat as far
back as possible
- use a child restraint system that is
suitable for the age, size and weight of
the child
- observe the manufacturer's installation
instructions in order to install and secure
the child restraint system correctly.
R For children larger than the typical 12-
month-old child, the front-passenger front
air bag may or may not be activated.
If the driver's air bag deploys, this does not
mean that the front-passenger front air bag
will also deploy.
The OCS may have detected that the seat:
R is either empty or occupied by a person
with a weight up to that of a typical twelve-
month-old child seated in a standard child
restraint
R is occupied by a small individual, such as a
young teenager or a small adult
R is occupied by a child in a child restraint
system, whose weight is greater than that
of a typical twelve-month-old child.
These are examples of when the OCS
deactivates the front-passenger front air bag
and front-passenger knee bag. Deactivation
takes place although the collision fulfills the
criteria for deploying the driver's air bag.
If the SmartKey has been removed from the
ignition lock or is in position 0,
44Occupant safetySafety

^a indicator lamp : does not light
up.
The _^ indicator lamp has no
function. It lights up briefly when the ignition
is switched on and then goes out again.GWARNING
If the red 6 SRS warning lamp in the
instrument cluster and the 4 PASSENGER
AIR BAG OFF indicator lamp light up
simultaneously, the OCS is malfunctioning.
The front-passenger front air bag and the
front-passenger knee bag will be deactivated
in this case. Have the system checked as soon
as possible by qualified technicians. Consult
an authorized Mercedes-Benz Center.
Only have the seat repaired at an authorized
Mercedes-Benz Center.
In order to ensure correct operation of the air
bag system and OCS:
R sit with the seat belt fastened correctly and
in a position that is as upright as possible
with your back against the backrest.
R while seated, an occupant should not
position themselves in such a way as to
cause their weight to be lifted from the seat
cushion as this may result in OCS being
unable to correctly assess the occupant's
weight category.
R read and observe all warnings in this
section.
System self-test
The ^a indicator lamp illuminates
when you:
R turn the SmartKey to position 1 or 2 in the
ignition lock
R press the KEYLESS-GO Start/Stop button
once or twice
If an adult occupant is sitting properly on the
front-passenger seat and the OCS classifies
the occupant as an adult, the ^a
indicator lamp will illuminate and go out again
after approximately six seconds.
If the seat is not occupied and the OCS
classifies the front passenger seat as being
unoccupied, the ^a indicator lamp
will illuminate and not go out.GWARNING
If the 4 PASSENGER AIR BAG OFF
indicator lamp does not illuminate, the system
is not functioning. Consult an authorized
Mercedes-Benz Center before seating a child
on the front-passenger seat.
For more information, see "Problems with the
Occupant Classification System"
( Y page 46).
GWARNING
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.
Occupant safety45SafetyZ

Problems with the Occupant Classification SystemProblemPossible causes/consequences and M SolutionsThe ^a
indicator lamp
illuminates and
remains illuminated.
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 childThe OCS is malfunctioning.XHave the OCS checked as soon as possible at an authorized
Mercedes-Benz Center.XObserve the additional display messages in the multifunction
display ( Y page 211).GWARNING
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.
ProblemPossible causes/consequences and M SolutionsThe ^a
indicator lamp does not
illuminate and/or does
not remain illuminated.
The front-passenger
seat is:
R unoccupied
R occupied with a
weight up to that of a
typical twelve-
month-old child in a
standard child
restraint systemThe OCS is malfunctioning.XMake sure there is nothing between the seat cushion and the
child seat.XCheck the installation of the child restraint system.XMake sure that no objects are applying additional weight onto
the seat.XIf the ^a indicator lamp does not illuminate, have the
OCS checked as soon as possible at an authorized Mercedes-
Benz Center. Do not transport a child on the front-passenger
seat as long as the OCS is not functioning.XObserve the additional display messages in the multifunction
display ( Y page 211).GWARNING
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.
46Occupant safetySafety

PRE-SAFE®
(preventative occupant
protection)
i AMG vehicles do not include the PRE-
SAFE ®
system.GWARNING
The PRE-SAFE ®
system reduces the impact of
an accident on vehicle occupants, as long as
their seat belts have been fastened correctly.
Although your vehicle is equipped with a PRE-
SAFE ®
system, the possibility of injury in the
event of an accident cannot be ruled out. You
should therefore always drive carefully and
adapt your driving style to the prevailing road,
weather and traffic conditions.
PRE-SAFE ®
takes preemptive measures to
protect occupants in certain hazardous
situations.
PRE-SAFE ®
intervenes:
R if BAS intervenes, e.g. in emergency
braking situations
R if BAS PLUS intervenes powerfully on
vehicles with DISTRONIC PLUS
R if, on vehicles with DISTRONIC PLUS, the
radar sensor system detects an imminent
danger of collision in certain situations
R in critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the seat belts are pre-tensioned.
R on vehicles with memory function for the
front-passenger seat: the front-passenger
seat is adjusted if it is in an unfavorable
position.
R if the vehicle skids, the side windows are
closed so that only a small gap remains.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pretensioning. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:XMove the backrest or seat back slightly, but
only when the vehicle is stationary.
The belt pretensioning is reduced and the
locking mechanism is released.GWARNING
Make sure that nobody can become trapped
as you adjust the seat.
! 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.
More information about seat-belt
adjustment, a convenience function
integrated into PRE-SAFE ®
, can be found in
the "Seat-belt adjustment" section
( Y page 51).
NECK-PRO head restraints
The NECK-PRO head restraints increase
protection to the driver's and front
passenger's head and neck. To this end, 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.
GWARNING
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.
GWARNING
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
Occupant safety47SafetyZ

therefore not provide the intended protection.
Do not use any seat or head restraint covers.
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 48). 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.GWARNING
For your protection, drive only with properly
positioned head restraints.
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.
Resetting triggered NECK-PRO head
restraints
GWARNING
For safety reasons, have the NECK-PRO head
restraints checked at an authorized
Mercedes-Benz Center after a rear-end
collision.
GWARNING
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.
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, e.g. an
authorized Mercedes-Benz Center.
XTilt the top of the NECK-PRO head restraint
cushion forwards in the direction of
arrow :.XPush the NECK-PRO head restraint cushion
down in the direction of arrow ; as far as
it will go.XFirmly push the NECK-PRO head restraint
cushion back in the direction of arrow =
until the cushion engages.XRepeat this procedure for the second
NECK-PRO head restraint.
Seat belts
Important 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 when the vehicle is in motion.
i For further information on infants and
children traveling in the vehicle and on
infant and child restraint systems, see
"Children in the vehicle" ( Y page 53).
GWARNING
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 considerably increases
48Occupant safetySafety