MERCEDES-BENZ SLK-Class 2013 R172 Service Manual
Manufacturer: MERCEDES-BENZ, Model Year: 2013, Model line: SLK-Class, Model: MERCEDES-BENZ SLK-Class 2013 R172Pages: 358, PDF Size: 4.61 MB
Page 41 of 358

tamper with electronic components or their
software.
In this section, you will lear nthe most
important facts about the restraint system
components of the vehicle.
The restraint system consists of:
R seat belts
R child restraint systems
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R NECK-PRO head restraints
R PRE-SAFE ®
R Air bag system components with:
-PASSENGER AIR BAG ON/OFF indicator
lamp 1
- Front-passenger seat with Occupant
Classification System (OCS)
The different air bag systems work
independently of each other. The protective
functions of the system work in conjunction
with each other. Not all air bags are always
deployed in an accident.
i See "Children in the vehicle" for
information on infants and children
traveling with you in the vehicle and
restraint systems for infants and children
(Y page 56). SRS (Supplemental Restraint System)
Introduction SRS consists of:
R
the 001B SRS warning lamp
R air bags
R the air bag control unit with crash sensors
R Emergency Tensioning Devices
R belt force limiters
SRS reduces the risk of occupants coming
into contact with the vehicle's interior in the event of an accident. It can also reduce the
effect of the forces to which occupants are
subjected during an accident.
SRS warning lamp G
WARNING
The SRS self-check has detected a
malfunction if the 001BSRS indicator lamp:
R does not light up at all
R does not go out after approximately four
seconds after the engine is started
R lights up after the engine is started or while
the vehicle is in motion
For your safety, Mercedes-Ben zstrongly
recommends tha tyou have the system
checked as soon as possible at a qualified
specialist workshop. SRS may otherwise fail
to activate when it is needed in the event of
an accident, which could lead to serious or
fatal injuries. SRS might also be activated
unexpectedly and unnecessarily, which could
also result in injury.
In addition, work carried out improperly on
SRS may render SRS inoperative or cause
unintended air bag deployment. Work on the
SRS system should only be carried out by
qualified specialist personnel. Consult a
qualified specialist workshop.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz Center
for details. USA only: for further information,
contact our Customer Assistance Center at
1-800-FOR-MERCedes (1-800-367-6372).
The 001B SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
SRS functions are checked regularly when the
engine is running. Therefore, malfunctions
can be detected in good time.
1 The PASSENGER AIR BAG ON indicator lamp has no function. When switching on the ignition, it lights up
briefly and then goes out again. Occupant safety
39Safety Z
Page 42 of 358

The SRS components are in operational
readiness when the SRS 001Bindicator lamp
goes out while the engine is running.
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags G
WARNING
R Damaged seat belts or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts
installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment.C heck your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R 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.
R No modifications of any kind may be made
to any components or wiring of the SRS.
R Do not change or remove any component
or part of the SRS.
R Do not install additional trim material, seat
covers, badges, etc. over the steering
wheel hub, front-passenger front air bag
cover, outer sides of the seat backrests,
door trim panels, or door frame trims.
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring. R
Keep area between air bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
R Air bag system components will be hot after
an air bag has inflated. Do not touch them.
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 Improper repair work on the SRS creates a
risk of rendering the SRS inoperative or
causing unintended air bag deployment.
Work on the SRS must therefore only be
performed by qualified technicians.
Contact an authorized Mercedes-Benz
Center.
R For your protection and the protection of
others, when scrapping the air bag unit or
ETD, our safety instructions must be
followed. These instructions are available
from any authorized Mercedes-Benz
Center.
R Given the considerable deployment speed,
required inflation volume, and the material
of the air bags, there is the possibility of
abrasions or other, potentially more serious
injuries resulting from air bag deployment.
If you sell your vehicle, Mercedes-Benz
strongly recommends that you inform the
subsequent owner that the vehicle is
equipped with SRS. Also, refer them to the
applicable section in the Operator's Manual. 40
Occupant safetySafety
Page 43 of 358

Air bags
Important safety notes G
WARNING
Air bags are designed to reduce the incidence
of injuries and fatalities in certain situations:
R frontal impacts (driver's and front-
passenger fron tair bags and knee bags)
R side impacts (side impact air bags and head
bags)
R rollover (head bags)
However, no system available today can
completely eliminate injuries and fatalities.
When the air bags are deployed, a small
amount of powder is released .The powder
generally does not constitute a health hazard
and does not indicate that there is a fire in the
vehicle. In order to prevent potential
breathing difficulties, you should leave the
vehicle as soon as it is safe to do so. If you
have any breathing difficulty but cannot get
out of the vehicle after the air bag inflates,
then get fresh air by opening a window or
door. G
WARNING
In order to reduce the potential danger of
injuries caused during the deployment of the
front air bags, the driver and front passenger
must always be correctly seated and wear
their seat belts.
For maximum protection in the event of a
collision, you must always be in the normal
seat position with your back against the
backrest. Fasten your seat belt and make sure
that it is correctly positioned on your body. As the air bag inflates with considerable
speed and force, a proper seating position
and correct positioning of the hands on the
steering wheel will help to keep you at a safe
distance from the air bag. Occupants who are
not wearing their seat belt, are not seated
properly or are too close to the air bag can be
seriously injured or killed by an air bag, as it
inflates with great force instantaneously:
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 move the driver's seat as far back as
possible, still permitting proper operation
of vehicle controls. The distance from the
center of the driver's chest to the middle of
the air bag cover on the steering wheel
must be at least 10 inches (25 cm). You
should be able to accomplish this by
adjusting the seat and steering wheel. If
you have any difficulties, please contact a
qualified specialist workshop.
R do not lean your head or chest close to the
steering wheel or dashboard.
R only hold the steering wheel on the outside.
Placing hands and arms inside the rim of
the steering wheel can increase the risk
and potential severity of hand/arm injuries
if the air bag inflates.
R adjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
R occupants, especially children, should
never place their bodies or lean their heads
in the area of the door where the side
impact air bag and/or head bag inflates.
This could result in serious injuries or death
should the side impact air bag/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. Occupant safety
41Safety
Z
Page 44 of 358

If you sell yourv
ehicle, it is important that you
make the buyer aware of this safety
information. Be sure to give the buyer this
Operator's Manual. G
WARNING
If the side impact air bag and/or head bag is
deployed in the event of a side impact and the
fron tpassenger, especially achild, 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.
If the air bags 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. The 001BSRS warning lamp
lights up.
The air bags are deployed if the air bag control
unit detects the need for deployment.O nly in
the event of such a situatio nwill the air bags
provide their supplemental protection.
If the drive rand front passenge rdo not wear
their seat belts, 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 extentp ossible by a properly fastened
seat belt. Aproperly fastened seat belti s alsoneeded 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.
It is important for your safety and that of your
passengers 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 0003
Driver's air bag
0004 Front-passenger front air bag
0024 Front-passenger knee bag
0023 Driver's knee bag
Driver's air bag 0003deploys in front of the
steering wheel; front-passenger front air
bag 0004deploys in front of and above the glove
box.
The front air bags increase protection against
head and chest injuries.
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 42
Occupant safetySafety
Page 45 of 358

R
depending on whether the seat belt is being
used
R independently of other air bags in the
vehicle
If the vehicle overturns, the fron tair bags are
generally not deployed. If the system detects
high vehicle deceleration in alongitudinal
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 45).
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.
Front-passenger front air bag will only deploy
if:
R the system, based on the OCS weight
sensor readings, has detected that the
front-passenger seat is occupied.
R the 00030005 indicator lamp on the center
console is not lit (Y page 45).
R the air bag control unit predicts a high
impact severity. Knee bags Driver's knee bag
0023(Ypage 42) deploys
underneath the steering column and front-
passenger knee bag 0024(Ypage 42)
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.
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
Side impact air bags G
WARNING
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
doors must therefore only be performed by
qualified technicians. Contact an authorized
Mercedes-Benz Center. 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 side impact air bags. Contact an
authorized Mercedes-Benz Center for
availability. Occupant safety
43Safety Z
Page 46 of 358

Example: side impact ai
rbag on the driver's side
Side impac tair bags 0003deploy nex tto the
outer side bolsters of the seat backrest.
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
The 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 aside 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 impac tair
bags are generally not deployed. Side impact
air bags are deployed if the system detects
high vehicle deceleration or acceleration in a
lateral direction and determines that side
impac tair bag deploymen tcan offer
additional protection to that provided by the
seat belt.
Side impac tair bags will not deploy in side
impacts which do not exceed the system's
prese tdeployment 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 does not deploy under the
following conditions:
R
the OCS system detects that the front-
passenger seat is not occupied, and
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 bags Example: headbag on the front-passenger side
Headbags
0003deploy in the area of the side
windows at the front.H eadbags enhance the
level of protection for the head, but not chest
or arms, of the vehicle occupants on the side
of the vehicle on which the impact occurs.
The headbags are deployed:
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in aside impact
R on the side on which an impac toccurs
R on the driver's side and passenger side, in
the event of a vehicle rollover and if the
system determines that ai rbag 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 fron tair bags
Headbags will not deploy in side impacts
which do not exceed the system's preset 44
Occupant safetySafety
Page 47 of 358

deployment thresholds for lateral
acceleration/deceleration. You will then be
protected by the fastened seat belt.
The head bag on the front-passenger side is
not deployed in the following situations:
R the OCS system detects that the front-
passenger seat is not occupied, and
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)
Method of operation G
WARNING
If the 0017 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 0017PASSENGER AIR BAGO FF
indicator lamp goes out.
In the event of a collision, the air bag control
uni tw ill not allow front-passenge rfront air
bag and front-passenge rknee bag
deployment when the OC Shas 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.
When the OCS senses that the front-
passenger seat occupant is classified as
being up to or less than the weigh tofatypical
12-month-old child in a standard child
restraint, the 0017PASSENGER AIR BAG OFF
indicator lamp will illuminate when the engine
is started and remai nilluminated. This
indicates that the front-passenger front air bag and the front-passenge
rknee bag are
deactivated.
When the OCS senses that the front-
passenger sea tis classified as being empty,
the 0017 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 astandard child
restraint or as being a small individual (such
as a young teenager or asmall adult), the
0017 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 0017PASSENGER
AIR BAG OFF indicator lamp is illuminated, the
front-passenger front air bag and the front-
passenger knee bag are deactivated. If the
0017 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 0017PASSENGER 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 0017 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. Occupant safety
45Safety
Z
Page 48 of 358

If the
0017 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 G
WARNING
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.
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 yourv ehicle 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 fron tair 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-passenge rseat, make
sure the 0017PASSENGER AIR BAG OFF
indicator lamp is illuminated, indicating
that the front-passenger front air bag and
front-passenger knee bag are deactivated.
If the 0017 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 0017
PASSENGER AIR BAG OFF indicator lamp
while driving to make sure the 0017
PASSENGER AIR BAG OFF indicator lamp is
illuminated. If the 0017PASSENGER AIR
BAG OFF indicator lamp goes out or
remains out do not carry a child on the
front-passenger seat.
R Ac hild 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 achild 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. 46
Occupant safetySafety
Page 49 of 358

G
WARNING
If the red 001BSRS warning lamp in the
instrument cluster and the 0017PASSENGER
AIR BAG OFF indicator lamp light up
simultaneously, the OCS is malfunctioning.
The front-passenger front air bag and the
front-passenge rknee 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 sea trepaired 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 away as to
cause their weigh tto 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. If the key has been removed from the ignition
lock or is in position 0, the00030005
indicator lamp 0003does not light up.
The 00030004 indicator lamp 0004is
inoperative. It lights up briefly when the
ignition is switched on and then goes out
again.
Occupant Classification System (OCS)
categories 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
00030005 indicator lamp 0003shows you
the current status. If the 00030005indicator
lamp 0003lights up, the front-passenger air bag
and the front-passenger knee bag are
disabled.
The OCS weight sensor reading is affected if
the occupant's weight is transferred, e.g. by
leaning on the armrest.
Both the driver and the front passenger
should always observe the 00030005
indicator lamp 0003to determine whether or
not the front passenger is positioned
correctly. Also observe the air bag display
messages, which appear in the instrument
cluster (Y page 221).
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 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 empty or occupied by the weight of a
typical child up to twelve months old,
seated in a child restraint system
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 Occupant safety
47Safety Z
Page 50 of 358

takes place although the collision fulfills the
criteria for deploying the driver's ai
rbag.
If the front-passenger seat, the seat cover or
the seat cushion are damaged, have the
necessary repai rwork carried out at a
qualified specialist workshop.
Mercedes-Benz recommends that you only
use seat accessories which have been
approved by Mercedes-Benz.
System self-test G
WARNING
If the 0017 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. G
WARNING
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.
The 00030005 indicator lamp lights up:
R if you turn the SmartKey in the ignition lock
to position 1or 2
R if you press the KEYLESS-GO Start/Stop
button once or twice on vehicles with
KEYLESS-GO
R if an adult is seated properly on the front-
passenger seat and the OCS classifies the
occupant as an adult
The 00030005 indicator lamp goes out after
approximately 6seconds. If the seat is not occupied and the OCS
detects that the front-passenger seat is
empty, the 00030005indicator lamp will
continue to light up. The 00030005front-
passenger fron tair bag warning lamp then
stays lit continuously.
For more information about the OCS, see
"Problems with the Occupant Classification
System" (Y page 49). 48
Occupant safetySafety