2017 MERCEDES-BENZ CLA ABS

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

Braking assistance appropriate to the situation
can also detect stationary objects, up to vehicle
speeds of around 44 mph 70 km/h. X
Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if: R
you release the brake pedal. R
there is no longer any danger of a collision. R
no obstacle is detected in front of your vehi-
cle.
Braking assistance appropriate to the situation
is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems ( Y
page 60).
G WARNING
Adaptive Brake Assist does not react: R
to people or animals R
to oncoming vehicles R
to crossing traffic R
when cornering
As a result, Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
G WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist might: R
intervene unnecessarily R
not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. Terminate the
intervention in a non-critical driving situation.
Due to the nature of the system, complex but
non-critical driving conditions may also cause
Active Brake Assist to intervene.
Even if Active Brake Assist is not available due to
a malfunction in the radar sensor system, the brake system is still available with full brake
boosting effect and BAS.
ESP ®
(Electronic Stability Program)
General notes
i Observe the "Important safety notes" sec-
tion ( Y
page 60).
ESP ®
monitors driving stability and traction, i.e.
power transmission between the tires and the
road surface.
If ESP ®
detects that the vehicle is deviating from
the direction desired by the driver, one or more
wheels are braked to stabilize the vehicle. The
engine output is also modified to keep the vehi-
cle on the desired course within physical limits.
ESP ®
assists the driver when pulling away on
wet or slippery roads. ESP ®
can also stabilize
the vehicle during braking.
ETS/4ETS (Electronic Traction System)
i Observe the "Important safety notes" sec-
tion ( Y
page 60).
ETS traction control is part of ESP ®
. On vehicles
with 4MATIC, 4ETS is part of ESP ®
.
Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side. In addition, more drive torque is transfer-
red to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP ®
.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 60).
G WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further driv-
ing safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.Driving safety systems 63
Safety Z

Parking Assist PARKTRONIC
Important safety notes Parking Assist PARKTRONIC is an electronic
parking aid with ultrasound. It monitors the area
around your vehicle using six sensors in the
front bumper and six sensors in the rear
bumper. Parking Assist PARKTRONIC visually
and audibly indicates the distance between your
vehicle and an object.
Parking Assist PARKTRONIC is only an aid. It is
not a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking and
exiting a parking space. When maneuvering,
parking or pulling out of a parking space, make
sure that there are no persons, animals or
objects in the area in which you are maneuver-
ing.
! When parking, pay particular attention to
objects above or below the sensors, such as
flower pots or trailer drawbars. Parking Assist
PARKTRONIC does not detect such objects
when they are in the immediate vicinity of the
vehicle. You could damage the vehicle or the
objects.
The sensors may not detect snow and other
objects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic car
wash, the compressed-air brakes of a truck or
a pneumatic drill could cause Parking Assist
PARKTRONIC to malfunction.
Parking Assist PARKTRONIC may not function
correctly on uneven terrain.
Parking Assist PARKTRONIC is activated auto-
matically when you: R
switch on the ignition R
shift the transmission to position D , R or NR
release the electric parking brake
Parking Assist PARKTRONIC is deactivated at
speeds above 11 mph (18 km/h). It is reactiva-
ted at lower speeds. Range of the sensors General notes Parking Assist PARKTRONIC does not take into
account obstacles located: R
below the detection range, e.g. people, ani-
mals or objects. R
above the detection range, e.g. overhanging
loads, tail sections or loading ramps of goods
vehicles.
C
Sensors in the front bumper, left-hand side
(example)
The sensors must be free from dirt, ice or slush.
They can otherwise not function correctly. Clean
the sensors regularly, taking care not to scratch
or damage them ( Y
page 262).
Range
C
Detection range of front sensors
D
Detection range of rear sensors160
Driving systems
Driving and parking

Important safety notes
G WAR NING
Lane Kee pin g Assist may not always clearly
recognize lane markings.
In th is case, Lane Kee pin g Assist may:R
give an unnecessary warning R
not give a warning
There is a risk of an acc iden t.
Always pay particular attention to the traff ic
situation and stay in lane, in particular if
warned by Lane Kee pin g Assist.
G WAR NING
The Lane Kee pin g Assist warning does not
return the veh icle to the original lane. There is
a risk of an acc iden t.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Kee p-
ing Assist.
If you fail to adapt your driv ing style, Lane Kee p-
ing Assist can neither reduce the risk of an acc i-
dent nor overr ide the laws of physics. Lane
Kee pin g Assist cannot take into account the
road, traff ic and weather conditions. Lane Kee p-
ing Assist is merely an aid. You are respon sible
for the dist ance to the veh icle in front, for veh i-
cle spee d, for braking in good time and for stay-
ing in your lane.
The Lane Kee pin g Assist does not keep the veh i-
cle in the lane.
The system may be impaired or may not function
if: R
there is poor vis ibilit y, e.g. due to insuff icie nt
illumi nation of the road, or due to snow, rain,
fog or spray R
there is glare, e.g. from oncoming traffic, the
sun or reflection from other veh icle s (e.g. if
the road surface is wet)R
the win dshield is dirt y, fogged up, damaged or
covered, for instance by a sticker, in the vicin-
ity of the camera R
there are no, several or unclear lane markings
for a lane, e.g. in areas wit h road construction
work R
the lane markings are worn away, dark or cov-
er ed up, e.g. by dirt or snow R
the distance to the vehicle in front is too small
and the lane markings thus cannot be detec-
ted R
the lane markings change quickly, e.g. lanes
branch off, cross one another or merge R
the road is narrow and win dingR
there are highly variable shade conditions on
the roadway
Switching on Lane Keeping Assist X
Swit ch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive ( Y
page 183).
If you drive at spee ds above 40 mph
(60 km/ h) and lane markings are detected,
the lines in the assistance graphics display
( Y
page 182) are shown in green. Lane Keep-
ing Assist is ready for use.
If Standard is selected, no warning vibration
occurs if: R
you have switched on the turn signal. In this
event, the warnings are suppressed for a cer-
tain period of time. R
a driving safety system intervenes, e.g. ABS,
BAS or ESP ®
.
When Adaptive
is selected, no warning vibra-
tion occurs if: R
you have switched on the turn signal. In this
event, the warnings are suppressed for a cer-
tain period of time. R
a driving safety system intervenes, e.g. ABS,
BAS or ESP ®
. R
you accelerate hard, e.g. kickdown. R
you brake hard. R
you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly. R
you cut the corner on a sharp bend.
In order that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, the system recognizes certain conditions
and warns you accordingly.
The warning vibration occurs earlier if: R
you approach the outer lane marking on a
bend. R
the road has very wide lanes, e.g. a highway. R
the system detects solid lane markings.
The warning vibration occurs later if: R
the road has narrow lanes. R
you cut the corner on a bend.Driving systems 173
Driving and parking Z

Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions
%
Q The yellow ABS warning lamp is lit while the engine is running.
ABS (Anti-lock Braking System) is deactivated due to a malfunction. BAS (Brake
Assist), Active Brake Assist, ESP ®
(Electronic Stability Program), the HOLD func-
tion and hill start assist are also deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions listed
above. The wheels could therefore lock if you brake hard, for example.
The steerability and braking characteristics may be severely affected. The braking
distance in an emergency braking situation can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident. X
Observe the additional display messages in the multifunction display. X
Drive on carefully. X
Visit a qualified specialist workshop immediately.
If the ABS control unit is faulty, there is also a possibility that other systems, such
as the navigation system or the automatic transmission, will not be available.
%
Q The yellow ABS warning lamp is lit while the engine is running.
ABS is temporarily unavailable. BAS, Active Brake Assist, ESP ®
, EBD (Electronic
Brake-force Distribution), the HOLD function and hill start assist are also deacti-
vated, for example.
Possible causes are: R
Self-diagnosis is not yet complete. R
The on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions listed
above. The front and rear wheels could therefore lock if you brake hard, for exam-
ple.
The steerability and braking characteristics may be severely affected. The braking
distance in an emergency braking situation can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is a risk of an accident. X
Carefully drive a suitable distance, making slight steering movements at a speed
above 12 mph (20 km/h).
The functions mentioned above are available again when the warning lamp goes
out.
If the warning lamp is still on: X
Observe the additional display messages in the multifunction display. X
Drive on carefully. X
Visit a qualified specialist workshop immediately.218
Warning and indicator lamps in the instrument cluster
On-board computer and displays

Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions
%
Q The yellow ABS warning lamp is lit while the engine is running. A warning tone
also sounds.
EBD is malfunctioning. ABS, BAS, Active Brake Assist, ESP ®
, the HOLD function
and hill start assist, for example, are also unavailable.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions listed
above. The front and rear wheels could therefore lock if you brake hard, for exam-
ple.
The steerability and braking characteristics may be severely affected. The braking
distance in an emergency braking situation can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident. X
Observe the additional display messages in the multifunction display. X
Drive on carefully. X
Visit a qualified specialist workshop immediately.
%

Tire pressure reached
G WARNING
A tire temporarily sealed with tire sealant
impairs the driving characteristics and is not
suitable for higher speeds. There is a risk of
accident.
You should therefore adapt your driving style
accordingly and drive carefully. Do not exceed
the specified maximum speed with a tire that
has been repaired using tire sealant.
The maximum permissible speed for a tire
sealed with tire sealant is 50 mph (80 km/h).
The upper part of the TIREFIT sticker must be
affixed to the instrument cluster in the driver's
field of vision.
If a tire pressure of 200 kPa (2.0 bar/29 psi) has
been attained after ten minutes: X
Switch off the tire inflation compressor. X
Unscrew the filler hose from the valve of the
faulty tire.
Note that tire sealant may escape when you
unscrew the filler hose. X
Stow the tire sealant bottle and the tire infla-
tion compressor. X
Pull away immediately .X
Stop after driving for approximately ten
minutes and check the tire pressure with the
tire inflation compressor.
The tire pressure must now be at least
130 kPa (1.3 bar/19 psi).
G WARNING
If the required tire pressure is not reached
after driving for a short period, the tire is too
badly damaged. The tire sealant cannot repair
the tire in this instance. Damaged tires and a
tire pressure that is too low can significantly
impair the vehicle's braking and driving char-
acteristics. There is a risk of accident.
Do not continue driving. Contact a qualified
specialist workshop.
i In cases such as the one mentioned above,
contact an authorized Mercedes-Benz Cen-
ter. Or call 1-800-FOR-MERCedes (in the
USA) or 1-800-387-0100 (in Canada). X
Correct the tire pressure if it is still at least
130 kPa (1.3 bar/19 psi). See the Tire and
Loading Information placard on the driver's
side B-pillar or the tire pressure table in the
fuel filler flap for values. X
To increase the tire pressure: switch on the
tire inflation compressor.
X
When the tire pressure is correct, unscrew the
filler hose from the valve of the sealed tire.
Note that tire sealant may escape when you
unscrew the filler hose. X
Screw the valve cap onto the tire valve of the
sealed tire.
X
To remove the tire sealant bottle from the tire
inflation compressor, press together the lock-
ing tabs on the yellow cap. X
Pull the tire sealant bottle out of the tire infla-
tion compressor.
The filler hose remains attached to the tire
sealant bottle. X
Drive to the nearest qualified specialist work-
shop and have the tire changed there. X
Have the tire sealant bottle and the filler hose
replaced as soon as possible at a qualified
specialist workshop. X
Have the tire sealant bottle replaced every
four years at a qualified specialist workshop.270
Flat tire
Breakdown assistance

Battery (vehicle)
Important safety notes Special tools and expert knowledge are required
when working on the battery, e.g. removal and
installation. You should therefore have all work
involving the battery carried out at a qualified
specialist workshop.
G WARNING
Work carried out incorrectly on the battery
can lead, for example, to a short circuit and
thus damage the vehicle electronics. This can
lead to function restrictions applying to
safety-relevant systems, e.g the lighting sys-
tem, the ABS (anti-lock braking system) or the
ESP ®
(Electronic Stability Program). The oper-
ating safety of your vehicle may be restricted.
You could lose control of the vehicle, for
example: R
when braking R
in the event of abrupt steering maneuvers
and/or when the vehicle's speed is not
adapted to the road conditions
There is a risk of an accident.
In the event of a short circuit or a similar inci-
dent, contact a qualified specialist workshop
immediately. Do not drive any further. You
should have all work involving the battery car-
ried out at a qualified specialist workshop.
For further information about ABS and ESP ®
,
see ( Y
page 60) and ( Y
page 63).
G WARNING
Electrostatic build-up can lead to the creation
of sparks, which could ignite the highly explo-
sive gases of a battery. There is a risk of an
explosion.
Before handling the battery, touch the vehicle
body to remove any existing electrostatic
build-up.
The highly flammable gas mixture forms when
charging the battery as well as when jump-start-
ing. Always make sure that neither you nor the bat-
tery is electrostatically charged. A build-up of
electrostatic charge can be caused, for exam-
ple: R
by wearing clothing made from synthetic
fibers R
due to friction between clothing and seats R
if you push or pull the battery across the car-
pet or other synthetic materials R
if you rub the battery with a cloth
G WARNING
During the charging process, a battery produ-
ces hydrogen gas. If a short circuit occurs or
sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion. R
Make sure that the positive terminal of a
connected battery does not come into con-
tact with vehicle parts. R
Never place metal objects or tools on a bat-
tery. R
It is important that you observe the descri-
bed order of the battery terminals when
connecting and disconnecting a battery. R
When jump-starting, make sure that the
battery poles with identical polarity are
connected. R
It is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables. R
Never connect or disconnect the battery
terminals while the engine is running.
G WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with
plenty of clean water and seek medical atten-
tion.
H Environmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them withBattery (vehicle) 271
Breakdo wn assis tance Z