warning MERCEDES-BENZ CLA 2017 Owner's Guide

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.
G WARNING
Emergency Tensioning Devices that have
deployed pyrotechnically are no longer opera-
tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Have pyrotechnically triggered Emergency
Tensioning Devices replaced immediately at a
qualified specialist workshop.
If Emergency Tensioning Devices are triggered
or air bags are deployed, you will hear a bang,
and a small amount of powder may also be
released. The u restraint system warning
lamp lights up.
Only in rare cases will the bang affect your hear-
ing. The powder that is released generally does
not constitute a health hazard, but it may cause
short-term breathing difficulties in people with
asthma or other respiratory problems. Provided
it is safe to do so, you should leave the vehicle
immediately or open the window in order to pre-
vent breathing difficulties.
Air bags and pyrotechnic Emergency Tensioning
Devices (ETDs) contain perchlorate material,
which may require special handling and regard
for the environment. National guidelines must
be observed during disposal. In California, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm .
Method of operation During the first stage of a collision, the restraint
system control unit evaluates important physi-
cal data relating to vehicle deceleration or accel-
eration, such as: R
duration R
direction R
intensity
Based on the evaluation of this data, the
restraint system control unit triggers the Emer-
gency Tensioning Devices during a frontal or
rear collision. An Emergency Tensioning Device can only be
triggered, if: R
the ignition is switched on R
the components of the restraint system are
operational. You can find further information
under: "Restraint system warning lamp"
( Y
page 40) R
the seat belt buckle tongue has engaged in
the belt buckle of the respective front seat
The Emergency Tensioning Devices in the rear
compartment are triggered independently of the
lock status of the seat belts.
If the restraint system control unit detects a
more severe accident, further components of
the restraint system are activated independ-
ently of each other in certain frontal collision
situations: R
Front air bags as well as driver's and front-
passenger knee bags R
Window curtain air bag, if the system deter-
mines that deployment can offer additional
protection to that provided by the seat belt
The front-passenger front air bag is activated or
deactiv ated dependin g
on the person on the
front-passenger seat. The front-passenger front
air bag can only deploy in an accident if the
PASSENGER AIR BAG OFF indicator lamp is off.
Observe the information on the PASSENGER AIR
BAG indicator lamps ( Y
page 40).
Your vehicle has two-stage front air bags. During
the first deployment stage, the front air bag is
filled with propellant gas to reduce the risk of
injuries. The front air bag is fully deployed with
the maximum amount of propellant gas if a sec-
ond deployment threshold is reached within a
few milliseconds.
The activation threshold of the Emergency Ten-
sioning Devices and the air bag are determined
by evaluating the rate of vehicle deceleration or
acceleration which occurs at various points in
the vehicle. This process is pre-emptive in
nature. Deployment should take place in good
time at the start of the collision.
The rate of vehicle deceleration or acceleration
and the direction of the force are essentially
determined by: R
the distribution of forces during the collision R
the collision angle R
the deformation characteristics of the vehicle R
the characteristics of the object with which
the vehicle has collided52
Occupant safety
Safety

Factors which can only be seen and measured
after a collision has occurred do not play a deci-
sive role in the deployment of an air bag. Nor do
they provide an indication of air bag deploy-
ment.
The vehicle can be deformed considerably, with-
out an air bag being deployed. This is the case if
only parts which are relatively easily deformed
are affected and the rate of deceleration is not
high. Conversely, air bags may be deployed even
though the vehicle suffers only minor deforma-
tion. This is the case if, for example, very rigid
vehicle parts such as longitudinal body mem-
bers are hit, and sufficient deceleration occurs
as a result.
If the restraint system control unit detects a side
impact or if the vehicle rolls over, the applicable
components of the restraint system are activa-
ted independently of each other depending on
the apparent type of accident. R
Side impact air bags on the side where the
impact takes place, independently of the
Emergency Tensioning Device and the use of
the seat belt on the driver's seat and outer
seats in the second row
The side impact air bag on the front-
passenger side deploys under the following
conditions: -
the OCS system detects that the front-
passenger seat is occupied or -
the seat belt buckle tongue is engaged in
the belt buckle of the front-passenger seat R
Window curtain air bag on the side of impact,
independently of the u se of the seat belt and
independently of whether the front-
passenger seat is occupied R
Emergency Tensioning Devices, if the system
determines that deployment can offer addi-
tional protection in this situation R
Window curtain air bags on the driver's and
front-passenger side in certain situations
when the vehicle rolls over, if the system
determines that deployment can offer addi-
tional protection to that provided by the seat
belt
i Not all air bags are deployed in an accident.
The different air bag systems work independ-
ently of each other. How the air bag system works is determined
by the severity of the accident detected,
especially the vehicle deceleration or accel-
eration and the apparent type of accident: R
Frontal collision R
Side impact R
Rollover
Automatic measures after an acci-
dent Immediately after an accident, the following
measures are implemented, depending on the
type and severity of the impact: R
the hazard warning lamps are activated R
the emergency lighting is activated R
the vehicle doors are unlocked R
the front side windows are lowered R
the engine is switched off and the fuel supply
is cut off R
vehicles with mbrace: automatic emergency
call
Children in the vehicle
Important safety notes Accident statistics show that children secured
in the rear seats are safer than children secured
in the front-passenger seat. For this reason,
Mercedes-Benz strongly advises that you install
a child restraint system on a rear seat. Children
are generally better protected there.
If a child younger than twelve years old and
under 5 ft (1.50 m) in height is traveling in the
vehicle: R
always secure the child in a child restraint
system suitable for Mercedes-Benz vehicles.
The child restraint system must be appropri-
ate to the age, weight and size of the child R
be sure to observe the instructions and safety
notes in this section in addition to the child
restraint system manufacturer's installation
instructions R
be sure to observe the instructions and safety
notes on the "Occupant classification system
(OCS)" ( Y
page 46)Children in the vehicle 53
Safety Z

G WARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example: R
release the parking brake. R
shift the automatic transmission out of the
parking position P .R
start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
G WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
G WARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro-
tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in
the vehicle.
Always ensure that all vehicle occupants have
their seat belts fastened correctly and are sitting
properly. Particular attention must be paid to
children.
Observe the safety notes on the seat belt
( Y
page 41) and the notes on correct use of seat
belts ( Y
page 42).
A booster seat may be necessary to achieve
proper seat belt positioning for children over
41 lbs (18 kg) until they reach a height where a three-point seat belt can be properly fastened
without a booster seat.
Special seat belt retractor
G WARNING
If the seat belt is released while driving, the
child restraint system will no longer be
secured properly. The special seat belt retrac-
tor is disabled and the inertia real draws in a
portion of the seat belt. The seat belt cannot
be immediately refastened. There is an
increased risk of injury, possibly even fatal.
Stop the vehicle immediately, paying atten-
tion to road and traffic conditions. Reactivate
the special seat belt retractor and secure the
child restraint system properly.
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor.
When activated, the special seat belt retractor
ensures that the seat belt will not slacken once
the child restraint system has been secured.
Installing a child restraint system: X
Always comply with the child restraint system
manufacturer's installation instructions. X
Pull the seat belt smoothly from the belt out-
let. X
Engage the seat belt tongue in the belt buckle.
Activating the special seat belt retractor: X
Pull the seat belt out fully and let the inertia
reel retract it again.
While the seat belt is retracting, you should
hear a ratcheting sound. The special seat belt
retractor is activated. X
Push the child seat restraint system down so
that the seat belt is tight and does not loosen.
Removing a child restraint system and deacti-
vating the special seat belt retractor: X
Always comply with the child restraint system
manufacturer's installation instructions. X
Press the release button of the belt buckle,
hold the belt tongue firmly and guide it back
towards the belt outlet.
The special seat belt retractor is deactivated.54
Children in the vehicle
Safety

Child restraint system The use of seat belts and child restraint systems
is required by law in: R
all 50 states R
the U.S. territories R
the District of Columbia R
all Canadian provinces
If you install a rearward-facing child restraint
system on the center rear seat, the rear arm rest
must be folded back as far as possible.
You can obtain further information about the
correct child restraint system from any author-
ized Mercedes-Benz Center.
G WARNING
If the child restraint system is installed incor-
rectly on a suitable seat, it cannot protect as
intended. The child cannot then be restrained
in the event of an accident, heavy braking or
sudden changes of direction. There is an
increased risk of injury, possibly even fatal.
Make sure that you observe the child restraint
system manufacturer's installation instruc-
tions and the notes on use. Please ensure,
that the base of the child restraint system is
always resting completely on the seat cush-
ion. Never place objects, e.g. cushions, under
or behind the child restraint system. Only use
child restraint systems with the original cover
designed for them. Only replace damaged
covers with genuine covers.
G WARNING
If the child restraint system is installed incor-
rectly or is not secured, it can come loose in
the event of an accident, heavy braking or a
sudden change in direction. The child
restraint system could be thrown about, strik-
ing vehicle occupants. There is an increased
risk of injury, possibly even fatal.
Always install child restraint systems prop-
erly, even if they are not being used. Make
sure that you observe the child restraint sys-
tem manufacturer's installation instructions.
You will find further information on stowing
objects, luggage or loads under "Loading guide-
lines" ( Y
page 233). G WARNING
Child restraint systems or their securing sys-
tems which have been damaged or subjected
to a load in an accident can no longer protect
as intended. The child cannot then be
restrained in the event of an accident, heavy
braking or sudden changes of direction. There
is an increased risk of injury, possibly even
fatal.
Replace child restraint systems which have
been damaged or subjected to a load in an
accident as soon as possible. Have the secur-
ing systems on the child restraint system
checked at a qualified specialist workshop,
before you install a child restraint system
again.
The securing systems of child restraint systems
are: R
the seat belt system R
the LATCH-type (ISOFIX) securing rings R
the Top Tether anchorages
If it is absolutely necessary to carry a child on
the front-passenger seat, be sure to observe the
information on the "Occupant Classification
System (OCS)" ( Y
page 46). There you will also
find information on deactivating the front-
passenger front air bag.
All child restraint systems must meet the fol-
lowing standards: R
U.S. Federal Motor Vehicle Safety Standards
213 and 225 R
Canadian Motor Vehicle Safety Standards
213 and 210.2
Confirmation that the child restraint system cor-
responds to the standards can be f ound on an
in struction label on the child restraint system.
This confirmation can also be found in the instal-
lation instructions that are included with the
child restraint system.
Observe the warning labels in the vehicle inte-
rior and on the child restraint system.Children in the vehicle 55
Safety Z

LATCH-type (ISOFIX) child seat secur-
ing system
G WARNING
LATCH-type (ISOFIX) child restraint systems
do not offer sufficient protective effect for
children whose weight is greater than 48 lbs
(22 kg) who are secured using the safety belt
integrated in the child restraint system. In the
event of an accident, a child might not be
restrained correctly. This poses an increased
risk of injury or even fatal injury.
If the child weighs more than 48 lbs (22 kg),
only use LATCH-type (ISOFIX) child restraint
systems with which the child is also secured
with the vehicle seat belt. Also secure the
child restraint system with the Top Tether
belt, if available.
Always comply with the manufacturer's instal-
lation and operating instructions for the child
restraint system used.
Before every trip, make sure that the LATCH-
type (ISOFIX) child restraint system is engaged
correctly in both LATCH-type (ISOFIX) securing
rings
! When installing the child restraint system,
make sure that the seat belt for the middle
seat does not get trapped. The seat belt could
otherwise be damaged.
X
Install the LATCH-type (ISOFIX) child restraint
system on both LATCH-type (ISOFIX) securing
rings C .
ISOFIX is a standardized securing system for
specially designed child restraint systems on
the rear seats. LATCH-type (ISOFIX) securing
rings for two LATCH-type (ISOFIX) child restraint systems are installed on the left and right of the
rear seats.
Non-LATCH-type (ISOFIX) child seats may also
be used and can be installed using the vehicle's
seat belt system. Install the child seat according
to the manufacturer's instructions.
Top Tether
Introduction Top Tether provides an additional connection
between the child restraint system secured with
a LATCH-type (ISOFIX) system and the vehicle.
This helps reduce the risk of injury even further.
If the child restraint system is equipped with a
Top Tether belt, this should always be used.
Important safety notes
G WARNING
If the rear seat backrests are not locked, they
could fold forwards in the event of an acci-
dent, heavy braking or sudden changes of
direction. As a result, child restraint systems
cannot perform their intended protective
function. Rear seat backrests that are not
locked can also cause additional injuries, e.g.
in the event of an accident. This poses an
increased risk of injury or even fatal injury.
Always lock rear seat backrests after instal-
ling a Top Tether belt. Observe the lock veri-
fication indicator. Adjust the rear seat backr-
ests so that they are in an upright position.
If the rear backrest is not engaged and locked,
the red lock verification indicator will be visible
( Y
page 236).56
Children in the vehicle
Safety

Rearward-facing child restraint system If it is absolutely necessary to install a rearward-
facing child restraint system on the front-
passenger seat, always make sure that the
front-passenger front air bag is deactivated.
Only if the PASSENGER AIR BAG OFF indicator
lamp is permanently lit ( Y
page 40) is the front-
passenger front air bag deactivated.
Always observe the child restraint system man-
ufacturer's installation and operating instruc-
tions.
Forward-facing child restraint system If it is absolutely necessary to install a forward-
facing child restraint system on the front-
passenger seat, always move the front-
passenger seat as far back as possible. Fully
retract the seat cushion length. The entire base
of the child restraint system must always rest on
the seat cushion of the front-passenger seat.
The backrest of the child restraint system must
lie as flat as possible against the backrest of the
front-passenger seat. The child restraint system
must not touch the roof or be subjected to a load
by the head restraint. Adjust the angle of the
seat backrest and the head restraint position
accordingly. Always make sure that the shoul-
der belt strap is correctly routed from the vehi-
cle belt outlet to the shoulder belt guide on the
child restraint system. The shoulder belt strap
must be routed forwards and downwards from
the vehicle belt outlet. If necessary, adjust the
vehicle belt outlet and the front-passenger seat
accordingly.
Always observe the child restraint system man-
ufacturer's installation and operating instruc-
tions. Child-proof locks
Important safety notes
G WARNING
If children are traveling in the vehicle, they
could: R
open doors, thus endangering other people
or road users R
exit the vehicle and be caught by oncoming
traffic R
operate vehicle equipment and become
trapped
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are traveling in the
vehicle. When leaving the vehicle, always take
the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
Override feature for: R
the rear doors ( Y
page 59)R
the rear side windows ( Y
page 59)
G WARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example: R
release the parking brake. R
shift the automatic transmission out of the
parking position P .R
start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
G WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.58
Children in the vehicle
Safety

G WARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro-
tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in
the vehicle.
Child-proof locks for the rear doors
You secure each door individually with the child-
proof locks on the rear doors. A door secured
with a child-proof lock cannot be opened from
inside the vehicle. When the vehicle is unlocked,
the door can be opened from the outside. X
To activate: press the child-proof lock lever
up in the direction of arrow C .X
Make sure that the child-proof locks are work-
ing properly. X
To deactivate: press the child-proof lock
lever down in the direction of arrow D . Override feature for the rear side win-
dows X
To activate/deactivate: press button C .
If indicator lamp D is lit, operation of the rear
side windows is disabled. Operation is only
possible using the switches in the driver's
door. If indicator lamp D is off, operation is
possible using the switches in the rear com-
partment.
Pets in the vehicle
G WARNING
If you leave animals unattended or unsecured
in the vehicle, they could press buttons or
switches, for example.
As a result, they could: R
activate vehicle equipment and become
trapped, for example R
activate or deactivate systems, thereby
endangering other road users
Unsecured animals could also be flung around
the vehicle in the event of an accident or sud-
den steering or braking, thereby injuring vehi-
cle occupants. There is a risk of an accident
and injury.
Never leave animals unattended in the vehi-
cle. Always secure animals properly during
the journey, e.g. use a suitable animal trans-
port box.Pets in the vehicle 59
Safety Z

Drivin g safet y systems
Overview of drivin g safet y systemsIn this section , you will fin d information about
th e followin g drivin g safet y systems :R
AB S ( A n ti-loc k B rakin g S ystem)
( Y
page 60)R
BA S ( B rak e A ssist S ystem) ( Y
page 60)R
Active Brak e Assis t ( Y
page 61 )R
ES P ®
( E lectronic S t ability P r ogram)
( Y
page 63)R
EB D ( E lectroni c B rak e forc e D istribution )
( Y
page 66 )R
ADAPTIV E BRAKE ( Y
page 66 )R
STEE R CONTROL ( Y
page 66)
Important safet y notesIf you fail to adapt your drivin g style or if you are
inattentive , th e drivin g safet y systems can nei-
ther reduce th e ris k of an acciden t no r override
th e laws of physics. Driving safet y systems are
merely aids designed to assist driving. You are
responsible fo r maintainin g th e distanc e to th e
vehicle in front, fo r vehicle speed, fo r braking in
goo d time, and fo r stayin g in lane. Always adapt
your drivin g style to suit th e prevailin g road and
weather condition s and maintain a saf e distanc e
from th e vehicle in front. Drive carefully.
The drivin g safet y systems described only wor k
as effectively as possible when there is ade-
quat e contact between th e tires and th e road
surface. Please pay special attention to th e
note s on tires , recommended minimum tire
tread depths, etc. ( Y
page 282).
In wintr y drivin g conditions, always use winte r
tires (M+ S tires )a nd if necessary, snow chains.
Only in this way will the driving safety systems
described in this section work as effectively as
possible.
ABS (Anti-lock Braking System)
General information
ABS regulates brake pressure in such a way that
the wheels do not lock when you brake. This
allows you to continue steering the vehicle when
braking. The % ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface conditions.
ABS works on slippery surfaces, even when you
only brake gently.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 60).
G WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y
page 218) and dis-
play messages which may be shown in the
instrument cluster ( Y
page 189).
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit-
uation is over. X
To make a full brake application: depress
the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indication
of hazardous road conditions, and functions as a
reminder to take extra care while driving.
BAS (Brake Assist System)
General information
BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.60
Driving safety systems
Safety

Important safety notes
i Observ e th e "Importan t safet y notes" sec -
tion ( Y
page 60).
G WARNIN G
If BA S is malfunctioning , th e braking distanc e
in an emergenc y braking situation is
increased. Ther e is a ris k of an accident.
In an emergenc y braking situation , depress
th e brak e pedal wit h full force . AB S prevents
th e wheels from locking.
Braking X
Kee p th e brak e pedal firmly depressed until
th e emergenc y braking situation is over.
AB S prevents th e wheels from locking.
The brakes will function as usual once you
release th e brak e pedal . BA S is deactivated.
Active Brake Assist
General information
i Observ e th e "Importan t safet y notes" sec -
tion ( Y
page 60).
Active Brake Assist consist s of a distanc e warn -
ing function wit h an autonomous braking func-
tion and braking assistanc e appropriat e to th e
situation .
Active Brake Assist can help you to minimiz e th e
ris k of a collision wit h th e vehicl e traveling in
fron t or reduce th e effects of suc h a collision .
If Active Brake Assist detects that there is a ris k
of collision , you will be warned visually and
acoustically. If you do no t reac t to th e visual and
audible collision warning , autonomous braking
can be initiate d in critical situations. If you apply
th e brak e yourself in a critical situation , Adap-
tive Brake Assist support s you wit h braking
assistanc e appropriat e to th e situation .
Important safety notes
Detection of hazardous situation s can be par-
ticularly impaired by: R
there is dirt on th e sensor s or anythin g else
covering th e sensor sR
there is snow or heav y rainR
there is interferenc e by other radar source s R
there are stron g radar reflections, for exam-
ple in parking garages R
a narrow vehicl e is traveling in front, e.g. a
motorbike R
a vehicl e is traveling in fron t on a differen t lin eR
ne w vehicles or after servicing is carrie d out
on th e Active Brake Assist system
Observ e th e important safet y note s in th e
"Breaking-in notes" section ( Y
page 120).
Followin g damag e to th e fron t en d of th e vehicle,
hav e th e configuration and operation of th e
radar sensor checke d at a qualified specialist
workshop. This also applie s to collision s at low
speeds wher e no visible damag e to th e fron t of
th e vehicl e is apparent.
Activating/deactivating Active Brake Assist is active after every ignition
cycle.
You can activat e or deactivat e Active Brake
Assist ( Y
page 182) in th e on-board computer.
When deactivated, th e distanc e warning func-
tion and th e autonomous braking function are
also deactivated.
If Active Brake Assist is deactivated, th e

Thus, the distance warning function cannot
provide a warning in all critical situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
G WARNING
The distance warning function cannot always
clearly identify objects and complex traffic
situations.
In such cases, the distance warning function
may: R
give an unnecessary warning R
not give a warning
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and do not rely solely on the distance
warning function.
Function Starting at a speed of approximately 4 mph
(7 km/h), the distance warning function warns
you if you rapidly approach a vehicle in front. An
intermittent warning tone will then sound, and
the