MERCEDES-BENZ CLS 2014 Service Manual

Useful information..............................40
Panic alarm..........................................40
Occupant safety..................................40
Children in the vehicle........................60
Driving safetysystems.......................66
Theftdeterrent locking system.........73
39
Safety

Useful information
iThis Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please notethat your vehicle may
not be equipped with all features
described. This also applies to safety-
related systemsand functions.
iRead the information on qualified
specialist workshops: (Ypage 26).
Panic alarm
XTo activate:press\rbuttonfor at
least one second.
An alarm sounds and the exterior lighting
flashes.
XTo deactivate:press\rbutton
again.
or
XInsert the SmartKey intothe ignition lock.
or
XPress the KEYLESS-GO Start/Stop button.
The KEYLESS-GO key must be in the
vehicle.
Occupant safety
Important safetynotes
GWARNING
Modifications to the restraint systemscould
result in them not functioning properly any
more. The restraint systemscould then no
longer protect vehicle occupants as they are
designed to do and could fail in the eventof
an accidentoractivateunexpectedly, for
example. Thereisanincreased risk of injury.
Never modify partsoftherestraint systems.
Do notattempttomodify the wiring as well as
electronic components or their software.
If it is necessary to modify an air bag system
to accommodateaperson with disabilities,
contact an authorized Mercedes-Benz center.
USA only: for further information contact our
Customer Assistance Center at
1-800-FOR-MERCedes (1800-367-6372).
In this section,you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint system consistsof:
RSeat belts
RChild restraint systems
RLATCH-type (ISOFIX) child seat securing
system
Additional protection is provided by:
RSRS (Supplemental Restraint System)
RNECK-PRO head restraints/NECK-PRO
luxury head restraints
RPRE-SAFE®
RAir bag system components with:
-PASSENGER AIR BAG OFF indicator lamp
-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 deployed
in an accident.
40Occupant safety
Safety

iFor information on infants and children
traveling with youinthe vehicle as well as
restraint systems for infants and children,
see "Childreninthe vehicle"
(Ypage 60).
SRS (Supplemental Restraint System)
Introduction
RS consistsof:
RTheRS warning lamp
RAir bags
RThe air bag control unit with crash sensors
REmergency Tensioning Device for the front
seat belts and the outer seat belts in the
rear
RSeat belt force limiters for the front seat
belts and the outer seat belts in the rear
RS 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
GWARNING
If SRS is malfunctioning, child restraint
system components may be triggered
unintentionally or might not be triggered at all
in the event of an accident withahigh rate of
vehicle deceleration. There is an increased
risk of injury, possibly even fatal.
Have SRS checked and repaired immediately
ataqualified specialist workshop.
SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
TheSRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later thanafew seconds
after the engine is started.
The SRS components are in operational
readiness when theSRS indicator lamp
goes out while the engine is running.
There isamalfunction if:
RtheSRS warning lamp does not light
up when the ignition is switched on
Rthe engine is running and theSRS
warning lamp does not go out afterafew
seconds
Rthe engine is running and theSRS
warning lamp lights up again.
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags
GWARNING
RDamaged 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-BenzCenter.
RAir bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment. Check your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
RAir bags and ETDs are designed to function
onaone-time-only basis. An air bag or ETD
that has deployed must be replaced. PRE-
SAFE®has electrically operated reversible
belt tensionersinaddition to the
pyrotechnic ETDs.
RDo not pass seat belts over sharp edges.
They could tear.
RDo not make any modification that could
change the effectiveness of the seat belts.
RDo not bleach or dye seat belts as this may
severely weaken them. Inacrash they may
not be able to provide adequate protection.
Occupant safety41
Safety
Z

RNo modifications of any kind may be made
to any components or wiring of the SRS.
RDo not change or remove any component
or part of the SRS.
RDo not install additional trim material,seat
covers, badges, etc. to the:
-padded steering wheel boss
-knee bag covers
-front-passenger air bag cover
-outer side of front seat bolsters
-side trim next to the rear seat backrest
-roof lining trim
RDo not install additional electrical/
electronic equipment on or near SRS
components and wiring.
RKeep area between air bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
RDo not hang items such as coat hangers
from the coat hooks or handles over the
door. These items may be thrown around in
the vehicle and cause head and other
injuries when the window curtain air bag is
deployed.
RAir bag system components willbehot after
an air bag has inflated. Do not touch them.
RNever place yourfeet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
RImproper repairwork on the SRS creates a
risk of rendering the SRS inoperative or
causing unintended air bag deployment.
Work on the SRS must thereforeonly be
performed by qualified technicians.
Contact an authorized Mercedes-Benz
Center.
RFor 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.
RGiven 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
applicablesection in the Operator's Manual.
Air bags
Important safety notes
GWARNING
If you modify the air bag covers or affix objects
such as stickers to them, the air bags may not
function correctly. There is an increased risk
of injury.
Never modify the air bag covers or affix
objectstothem.
GWARNING
Using unsuitable seat covers could restrictor
even preventdeployment of the air bags
integrated into the seats. Consequently, the
air bags cannot protectvehicle occupantsas
they are designed to do. In addition, the
function of the air bag deactivation system
could be restricted. This poses an increased
risk of injury or even fatal injury.
You should only use seat coversthat have
been approved for the respective seat by
Mercedes-Benz.
GWARNING
The air bag parts are hot after the airbag has
been deployed. There isarisk of injury.
Do not touch the air bag parts. Have the
deployed air bags replaced ataqualified
specialist workshop as soon as possible.
42Occupant safety
Safety

GWARNING
Air bagsare designed to reduce the incidence
of injuriesand fatalities in certain situations:
Rfrontal impacts (driver's and front-
passenger front air bagsand knee bags)
Rside impacts (sideimpact air bags, window
curtainair bags and pelvis air bags)
Rrollover (window curtain air bags)
However, no system available today can
completely eliminate injuries and fatalities.
When the air bags are deployed,asmall
amount of powder is released.The powder
generally does not constituteahealth hazard
and does not indicate that there isafire 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 openingawindow or
door.
GWARNING
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,aproper seating position
and correct positioning of the hands on the
steering wheel will help to keep you atasafe
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:
Rsit with the seat belt fastened correctly and
inaposition that is as upright as possible
with your back against the backrest.
Rmove the driver's seat as far back as
possible, still permittingproper operation
of vehicle controls. The distance from the
center of the driver's chest to the center 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 an
authorized Mercedes-BenzCenter.
Rdo not lean your head or chest close to the
steeringwheel or dashboard.
Ronly hold the steeringwheel on the outside.
Placing hands and arms inside the rim can
increase the risk and potential severityof
hand/arm injury if the driver frontair bag
inflates.
Radjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
Roccupants, especially children,should
never place their bodies or lean their heads
in the area of the door where the side
impact air bag inflates.This could result in
serious or fatal injuries should the side
impact air 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 safety43
Safety
Z

If you sell yourvehicle, it is important that you
make the buyer aware of this safety
information.Besure to give the buyer this
Operator's Manual.
If the air bags are deployed, you will hear a
bang, andasmall 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 and does not indicatethat there
isafire in the vehicle. The dust might cause
some temporary breathingdifficulty for
people with asthma or other breathing
trouble. To avoid this, you may wish to get out
of the vehicle as soon as it is safe to do so.
You can also open the window to allow fresh
air to enter the vehicle interior. TheSRS
warning lamp lights up.
The air bag installation locationsare
identified by the AIR BAG symbol.
The air bags are deployed if the air bag control
unit detects the need for deployment. Only in
the event of suchasituation will the air bags
provide their supplemental protection.
If the driver and frontpassenger do notwear
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 passenger will then be protected
to the extent possible byaproperly fastened
seat belt.Aproperlyfastened seat beltisalso
needed to provide the best possible
protection inarollover.
Air bags provide additional protection; they
are not, however,asubstitute 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 ofacrash.
iAfter an air bag has been deployed, have
the vehicle towed to the nearest qualified
specialist workshop, even if your vehicle is
ready to drive.
Front air bags
Driver's air bagdeploysinfront of the
steering wheel; front-passenger front air
bagdeploysinfront of and above the glove
box.
The front air bags increase protection for the
driver's and front passenger's head and
chest.
They are deployed:
Rat the start of an accident withahigh rate
of vehicle acceleration or deceleration in a
longitudinal direction
Rin the event of certain frontal impacts
Rif the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
Rdepending on whether the seat belt is being
used
Rindependently of other air bags in the
vehicle
If the vehicle rolls over, the front air bags are
generally not deployed.
Your vehicle has adaptive, two-stage front air
bags. The air bag control unit evaluates
vehicle deceleration or acceleration in the
event ofacollision. In the first deployment
stage, the front air bag is filled with part of the
44Occupant safety
Safety

totalavailablepropellant gas, thereby
reducing the risk of injury.Ifthe airbag
control unitrecognizeswithinafew
milliseconds thatthe vehicle is being braked
or accelerated faster than originally
predicted, the front air bag is filled with the
maximum amount of propellant gas available.
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) (Ypage 47).
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 wherealow impact severity is
predicted. You will then be protected by the
fastened seat belt.
The front-passenger front air bag will only
deploy if:
Rthe system, based on the OCS weight
sensor readings, detectsthat the front-
passenger seat is occupied
Rthe PASSENGER AIR BAG OFF indicator
lamp on the center console is not lit
(Ypage 47)
Rthe air bag control unit predictsahigh
impact severity
Knee bags
Driver's knee bagdeploysunderneath the
steering column and front-passenger knee
bagunderneath 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:
Rknee injuries
Rthigh injuries
Rlower leg injuries
Side impact air bags
GWARNING
Using unsuitable seat covers could restrict or
even prevent deployment of the air bags
integrated into the seats. Consequently, the
air bags cannot protect vehicle occupants as
they are designed to do. In addition, the
function of the air bag deactivation system
could be restricted. This poses an increased
risk of injury or even fatal injury.
You should only use seat covers that have
been approved for the respective seat by
Mercedes-Benz.
GWARNING
Sensors to control the air bags are located in
the doors. Modifications or work not
performed correctly to the doors or door
paneling, as well as damaged doors, can lead
to the function of the sensors being impaired.
The air bags might therefore not function
properly any more. Consequently, the air bags
cannot protect vehicle occupants as they are
designed to do. There is an increased risk of
injury.
Never modify the doors or parts of the doors.
Always have work on the doors or door
paneling carried out ataqualified specialist
workshop.
Occupant safety45
Safety
Z

You should only use seat cover that have been
approved for your vehicle by Mercedes-Benz.
The seat covers must haveaspecial tear
seam for side impact air bags. Otherwise, the
side impact air bags cannot deploy correctly
and therefore cannot provide the intended
protection in the eventofanaccident.
Front side impact air bagsand rear side
impact air bagsdeploy nexttothe outer
seat cushions.
When deployed, the side impact air bags offer
additional protection for the thorax of the
vehicle occupantsonthe side of the vehicle
on which the impact occurs. However, they
do not protectthe:
Rhead
Rneck
Rarms
The side impact air bags are deployed:
Ron the side on which an impact occurs
Rat the start of an accident withahigh rate
of lateral vehicle deceleration or
acceleration, e.g. inaside impact
Rindependently of the use of the seat belt
Rindependently of the front air bags
Rindependently of the ETDs
If the vehicle rolls over,the side impact air
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
impact air bag deploymentcan offer
additional protection to that providedbythe
seat belt.
Sideimpactair bags will not deploy in side
impacts which do not exceed the system's
presetdeployment 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 is not deployed in the
following situations:
ROCS has detected that the front-passenger
seat is unoccupied.
Rthe 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.
Pelvis air bags
GWARNING
Only use seat covers which have been tested
and approved by Mercedes-Benz for your
vehicle model. Using seat covers or other seat
coverings can causeamalfunction of the side
impact air bags and/or the pelvis air bags.
Contact an authorized Mercedes-Benz Center
for availability.
Pelvis air bagsenhancethe level of
protection of the vehicle occupantsonthe
side of the vehicle on which the impact
occurs.
46Occupant safety
Safety

The pelvis air bags deploy next to and below
the outer seat cushions. They are deployed:
Ron the side on which an impact occurs
Rat the start of an accident withahigh rate
of lateral vehicle deceleration or
acceleration,e.g. inaside impact
Rindependently of the use of the seat belt
Rindependently of the front air bags
Rindependently of the ETDs
If the vehicle rolls over,the pelvis air bags are
generally not deployed. Exception: if the
system detectshigh vehicle deceleration or
acceleration inalateral direction and
determines that deploymentcan offer
additional protection to that providedbythe
seat belt.
Pelvis air bagswill notdeploy 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 pelvis air bag on the front-passenger side
is not deployed in the following situations:
ROCS has detected that the front-passenger
seat is unoccupied.
Rthe front-passenger seat belt is not
fastened.
The pelvis 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.
Window curtain air bags
Window curtain air bagsenhancethe level
of protection for the head, but not chest or
arms, of the vehicle occupantsonthe side of
the vehicle on which the impact occurs.
The window curtain air bags are integrated
into the side of the roof frame and deploy in
the area from the A-pillar to the C-pillar.
Window curtain air bags are deployed:
Rat the start of an accident withahigh rate
of lateral vehicle deceleration or
acceleration, e.g. inaside impact
Ron the side on which an impactoccurs
Ron the driver'ssideand passenger side, in
the event ofavehiclerollover and if the
system determinesthat airbag deployment
can offer thevehicle occupants additional
protection to that providedbytheseat belt
Rindependently of theuse of theseat belt
Rregardless of whether thefront-passenger
seat is occupied
Rindependently of thefrontair bags
Windowcurtain air bagswill not deploy in
the eventofimpacts which do not exceed the
system'spresetdeployment thresholds for
vehicle acceleration/deceleration. You will
then be protected by the fastened seat belt.
Occupant Classification System
(OCS)
Method of operation
GWARNING
If theindicator lamp illuminates
when an adult or someone larger thanasmall
individual is in the front-passenger seat, have
the front passenger reposition himself or
herself in the seat until the
indicator lamp goes out.
In the event ofacollision, the air bag control
unit will not allow front-passenger front air
bag deployment when the OCS has classified
the front-passenger seat occupant as
weighing as much as or less thanatypical 12-
month-old child inastandard child restraint
Occupant safety47
Safety
Z

or if the front-passenger seat is classified as
being empty.
When the OCS senses that the front-
passenger seat occupant is classified as
being up to or less than the weight ofatypical
12-month-old child inastandard child
restraint,theindicator lamp will
illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat is classified as being empty,
theindicator lamp will illuminate
when the engine is started and remain
illuminated, indicating that the front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat occupant is classified as
being heavier than the weight ofatypical 12-
month-old child seated inastandardchild
restraint or as beingasmall individual (such
asayoung teenager orasmall adult), the
indicator lamp willilluminate for
approximately6seconds when the engine is
started and then,depending on occupant
weight sensor readings from the front-
passenger seat, remain illuminated or go out.
With theindicator lamp
illuminated, the front-passenger frontair bag
is deactivated. With theindicator
lamp out, the front-passengerfront air bag is
activated.
When the OCS senses that the front-
passenger seat occupant is classifiedasan
adult or someone larger thanasmall
individual, theindicator lamp will
illuminate for approximately6seconds when
the engine is started and then go out,
indicating that the front-passenger frontair
bag is activated.
If theindicator lamp is illuminated,
the front-passenger frontair bag and the
front-passenger knee bag are deactivated and
will not be deployed.
If theindicator lamp is not
illuminated, the front-passenger frontair bag
and the front-passengerknee bagare
activatedand will be deployed:
Rin the event of certain frontalimpacts
Rif impact exceedsapreset deployment
threshold
Rindependentlyofthe side impact airbag or
pelvis air bag
If thefront-passenger frontair bag is
deployed, therateofinflation will be
influenced by:
Rtherateofrelevantvehicle deceleration as
assessed by the air bag control unit
Rthe frontpassenger's weightcategoryas
identified by OCS
GWARNING
Accordingtoaccidentstatistics, childrenare
saferwhen properly restrained on the rear
seats than on the front-passenger seat. Thus,
we strongly recommendthat children be
placed in the rear seats whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriate infant
restraint,toddler restraint,orbooster 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, the seat
belt and Top Tether strap, or lower LATCH-
type (ISOFIX) child seat retaining loops and
Top Tether strap, fully in accordance with the
infant or 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,orbooster seat
recommended for the size and weight of the
child.
Children can be killed or seriously injured by
an inflating air bag.
48Occupant safety
Safety