ABS MERCEDES-BENZ A-CLASS HATCHBACK 2015 User Guide

Pets in the vehicle
G
WARNING
If you leave animals unsupervised or unse-
cured in the vehicle, they may push a button
or a switch, for example.
They could:
R activate vehicle equipment and become
trapped, for example
R switch vehicle systems on or off, thus
endangering other road users
In the event of an accident, sudden braking or
abrupt changes of direction, unsecured ani-
mals could be flung around the vehicle, injur-
ing the vehicle occupants. There is a risk of an accident and injury.
Never leave animals unattended in the vehi-
cle. Always secure animals correctly during a
journey, e.g. in an animal transport box. Driving safety systems
Driving safety systems overview
In this section, you will find information about the following driving safety systems:
R ABS ( Anti-lock BrakingSystem)
(Y page 69)
R BAS ( Brake Assist System) (Y page 70)
R COLLISION PREVENTION ASSIST PLUS
(Y page 70)
R Adaptive brake lights (Y page 73)
R ESP ®
(Electronic StabilityProgram)
(Y page 73)
R EBD ( electronic brake force distribution)
(Y page 77)
R ADAPTIVE BRAKE (Y page 77)
R STEER CONTROL (Y page 77) Important safety notes
If you fail to adapt your driving style or if you
are inattentive, the driving safety systems can neither reduce the risk of an accident nor
override the laws of physics. Driving safety
systems are merely aids designed to assist
driving. You are responsible for maintaining
the distance to the vehicle in front, for vehicle speed, for braking in good time, and for stay-ing in lane. Always adapt your driving style to
suit the prevailing road and weather condi-
tions and maintain a safe distance from the
vehicle in front. Drive carefully.
The driving safety systems described only
work as effectively as possible when there is
adequate contact between the tyres and the
road surface. Please pay special attention to
the notes on tyres, recommended minimum
tyre tread depths etc. (Y page 358).
In wintry driving conditions, always use winter
tyres (M+S tyres) and, 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 notes ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi-
cle 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 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 69). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition- Driving safety systems
69Safety
Z

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.
If ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information on the ABS warning lamp (Y page 295) and
display messages which may be shown in the
instrument cluster (Y page 258).
Brakes X
If ABS intervenes: continue to depress the
brake pedal with force 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 indica-
tion of hazardous road conditions; this serves as a reminder to take extra care while driving. BAS (Brake Assist)
General notes BAS operates in emergency braking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 69). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking. Braking X
Keep the brake pedal depressed firmly until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. COLLISION PREVENTION ASSIST
PLUS
General notes i
Observe the "Important safety notes" sec-
tion (Y page 69).
COLLISION PREVENTION ASSIST PLUS con-
sists of a distance warning function with an
autonomous braking function and Adaptive
Brake Assist.
COLLISION PREVENTION ASSIST PLUS can
help you to minimise the risk of a collision
with the vehicle in front or reduce the effects of such a collision.
If COLLISION PREVENTION ASSIST PLUS
detects that there is a risk of a collision, you
will be warned visually and acoustically. If you
do not react to the visual and audible collision warning, autonomous braking can be initiated
in critical situations. If you apply the brake
yourself in a critical situation, the COLLISION PREVENTION ASSIST PLUS Adaptive Brake
Assist assists you.
Important safety notes Detection of hazardous situations can be par-
ticularly impaired by:
R dirt on the sensors or obscured sensors
R snow or heavy rain
R interference by other radar sources
R strong radar reflections, for example, in
multi-storey car parks
R a narrow vehicle travelling in front, e.g. a
motorcycle 70
Driving safety systemsSafety

X
Brake immediately in order to increase the
distance from the vehicle in front.
or
X Take evasive action provided it is safe to do
so.
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause the system to display a
warning.
With the help of the radar sensor system, the distance warning function can detect obsta-
cles that are in the path of your vehicle for an
extended period of time.
Up to a speed of approximately 70 km/h, the
distance warning function can also react to
stationary obstacles, such as stopped or
parked vehicles.
Autonomous braking function If the driver does not react to the distance
warning signal in a critical situation, COLLI-
SION PREVENTION ASSIST PLUS can assist
with the autonomous braking function.
The autonomous braking function:
R gives the driver more time to react to criti-
cal driving situations
R can help the driver to avoid an accident or
R reduces the effects of an accident
Due to the nature of the system, complicated but non-critical driving conditions may also
cause the Autonomous Braking function to
intervene.
If the autonomous braking function demands
particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously (Y page 56).
Adaptive Brake Assist General notes
i Observe the "Important safety notes" sec-
tion (Y page 69).
With the help of Adaptive Brake Assist, the
distance warning signal can detect obstacles that are in the path of your vehicle for an
extended period of time.
If Adaptive Brake Assist detects a risk of col-
lision with the vehicle in front, it calculates
the braking force necessary to avoid a colli-
sion. If you apply the brakes forcefully, Adap-
tive Brake Assist will automatically increase
the braking force to a level suitable for the
traffic conditions.
Adaptive Brake Assist provides braking assis- tance in hazardous situations at speeds
above 7 km/h. It uses radar sensor technol-
ogy to assess the traffic situation.
Up to a speed of approximately 250 km/h,
Adaptive Brake Assist is capable of reacting
to moving objects that have already been
detected as such at least once over the period
of observation.
Up to a speed of approximately 70 km/h,
Adaptive Brake Assist reacts to stationary
obstacles.
If Adaptive Brake Assist demands particularly high braking force, preventative passenger
protection measures (PRE-SAFE ®
) are activa-
ted simultaneously (Y page 56).
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
vehicle
Adaptive Brake Assist is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 69). G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions. 72
Driving safety systemsSafety

H
Environmental note Batteries contain pollutants.
It is illegal to dispose of them with the household rubbish.
They must be collected sep-
arately and disposed of in anenvironmentally responsible
recycling system. Dispose of batteries in an
environmentally responsible
manner. Take discharged
batteries to a qualified spe-
cialist workshop or to a col-
lection point for used batter-
ies.
Mercedes-Benz recommends that you have
the battery replaced at a qualified specialist
workshop.
Checking the battery X
Press the &or% button.
The battery is working properly if battery
check lamp :lights up briefly.
The battery is discharged if battery check
lamp :does not light up briefly.
X Replace the battery (Y page 86).
i If the key battery is checked within the
signal reception range of the vehicle, press- ing the &or% button:
R locks or
R unlocks the vehicle
i You can obtain a battery from any quali-
fied specialist workshop. Replacing the battery You require a CR 2025 3 V cell battery.
X Take the emergency key element out of the
key (Y page 85). X
Press emergency key element ;into the
opening in the key in the direction of the
arrow until battery tray cover :opens.
When doing so, do not hold cover :shut.
X Remove battery tray cover :. X
Repeatedly tap the key against your palm
until battery =falls out.
X Insert the new battery with the positive ter-
minal facing upwards. Use a lint-free cloth
to do so.
X Make sure that the surface of the battery is
free of lint, grease and other contamina-
tion.
X Insert the front tabs of battery tray cover :
and then press to close it.
X Insert emergency key element into the key
(Y page 85).
X Check the function of all key buttons on the
vehicle. 86
KeyOpening and closing

Also select the
Comfortdrive program when
driving fast on straight roads, e.g. on straight stretches of motorway.
X Press DYNAMIC SELECT button :
(Y page 166) repeatedly until the Comfort
drive program is selected.
Selecting Sport mode The firmer setting of the suspension tuning in
the Sport drive program ensures even better
contact with the road. Select this drive pro-
gram when employing a sporty driving style,
e.g. on winding country roads.
X Press DYNAMIC SELECT button :
(Y page 166) repeatedly until the Sport
drive program is selected. PARKTRONIC
Important safety notes PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It monitors the area
around your vehicle using six sensors in the
front bumper and six sensors in the rear
bumper. PARKTRONIC indicates visually and
audibly the distance between your vehicle
and an object.
PARKTRONIC is only an aid. It is not a substi- tute for your attention to the immediate sur-
roundings. The responsibility for safe
manoeuvring and parking remains with you.
Make sure that there are no persons, animals
or objects in range while manoeuvring and
parking.
! When parking, pay particular attention to
objects above or below the sensors, such
as flower pots or trailer drawbars.
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
objects which absorb ultrasonic sources. Ultrasonic sources, such as an automatic
car wash, a lorry's compressed-air brakes
or a pneumatic drill, could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
! Fold in the ball coupling if the trailer tow
hitch is not required. PARKTRONIC meas-
ures the minimum detection range to an
obstacle from the bumper, not the ball cou-
pling.
PARKTRONIC is activated automatically when you:
R switch on the ignition
R shift to position D,Ror Non vehicles with
automatic transmission
R release the electric parking brake
PARKTRONIC is deactivated at speeds above
18 km/h. It is reactivated at lower speeds.
PARKTRONIC is deactivated for the rear area
when you establish an electrical connection
between your vehicle and a trailer.
Range of the sensors General notes
PARKTRONIC does not take into account
obstacles located:
R below the detection range, e.g. persons,
animals or objects
R above the detection range, e.g. overhang-
ing loads, tail sections or loading ramps of
goods vehicles Driving systems
209Driving and parking Z

The system may be impaired or may not func-
tion if:
R there is poor visibility, e.g. due to insuffi-
cient illumination 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 vehicles
(e.g. if the road surface is wet)
R the windscreen is dirty, misted up, dam-
aged or covered, for instance by a sticker,
in the vicinity of the camera
R no or several, unclear lane markings are
present for one lane, e.g. in a construction
area
R the lane markings are worn away, dark or
covered 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
detected
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge
R the road is narrow and winding
R there are highly variable shade conditions
on the road
Activating Lane Keeping Assist X Activate Lane Keeping Assist using the on-
board computer; to do so, select Standard
Standard
or Adaptive Adaptive (Ypage 249).
If you drive at speeds above 60 km/h and
lane markings are detected, the lane mark-
ings in the assistance graphics display
(Y page 248) are shown in green.
When Standard Standard 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
certain period of time.
R a driving safety system intervenes, such as
ABS, BAS or ESP ®
.
When Adaptive
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
certain period of time.
R a driving safety system intervenes, such as
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 lane quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when nec-
essary and in good time if you cross the lane marking, the system detects certain condi-
tions 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 motor-
way
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 Towing a trailer
Important safety notes
G
WARNING
You could lose control of the vehicle/trailer
combination if it begins to swerve. The vehi-
cle/trailer combination could even overturn.
There is a risk of an accident.
On no account should you attempt to
straighten out the vehicle/trailer combina-
tion by increasing speed. Decrease your
speed and do not countersteer. Brake if nec-
essary. G
WARNING
If the maximum permissible load for a carrier system is exceeded, the carrier could come
loose from the vehicle and endanger other Towing a trailer
229Driving and parking
Z

Safety systems
Display messages
Possible causes/consequences and
M
MSolutions !÷
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual ABS (Anti-lock Braking System), BAS (Brake Assist System), ESP
®
(Electronic Stability Program), ESP ®
trailer stabilisation, the HOLD
function, hill start assist and PRE-SAFE ®
are temporarily unavail-
able.
The adaptive brake lights and COLLISION PREVENTION ASSIST
PLUS may also have failed.
In addition, the !,÷andå warning lamps may light up
in the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes:
R Self-diagnosis is not yet complete
R The on-board voltage may be insufficient.
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 affec-ted. The braking distance may increase in an emergency braking
situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above 20 km/h.
If the display message disappears, the functions mentioned
above are available again.
If the multifunction display still shows the display message:
X Drive on carefully.
X Consult a qualified specialist workshop immediately. !÷
inoperative See inoperative See
Owner's Manual Owner's Manual ABS, BAS, ESP
®
, ESP ®
trailer stabilisation, the HOLD function, hill
start assist and PRE-SAFE ®
are not available due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST
PLUS may also have failed.
The !, ÷, åandJ warning lamps may also light up
in the instrument cluster.
ATTENTION ASSIST is deactivated.
G WARNING 258
Display messagesOn-board computer/Displays

Display messages
Possible causes/consequences and
M
MSolutions ÷
inoperative See inoperative See
Owner's Manual Owner's Manual ESP
®
, ESP ®
trailer stabilisation, BAS, the HOLD function, hill start
assist and PRE-SAFE ®
are not available due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST
PLUS may also have failed.
In addition, the ÷andå warning lamps may light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the functions listed above.
The braking distance may thus increase in an emergency braking
situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. T!
÷
inoperative See inoperative See
Owner's Manual Owner's Manual EBD (electronic brake force distribution), ABS, BAS, ESP
®
, ESP ®
trailer stabilisation, the HOLD function, hill start assist and PRE-
SAFE ®
are not available due to a malfunction.
The adaptive brake lights and COLLISION PREVENTION ASSIST
PLUS may also have failed.
A warning tone sounds.
In addition, the ÷,åand! warning lamps may light up
in the instrument cluster.
G WARNING
The brake system continues to function normally, but without the functions listed above. The front and rear wheels could therefore
lock, for example, if you brake hard.
The steerability and braking characteristics may be severely affec-ted. The braking distance may increase in an emergency braking
situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. 260
Display
messagesOn-board computer/Displays

Problem
Possible causes/consequences and
M
MSolutions !
The yellow ABS warning
lamp is lit while the
engine is running. ABS (Anti-lock Braking System) has been deactivated due to a
fault. Therefore, BAS (Brake Assist System), COLLISION PREVEN-
TION ASSIST PLUS, ESP ®
(Electronic Stability Program), ESP ®
trailer stabilisation, the HOLD function, hill start assist, the adap-
tive brake lights and PRE‑SAFE ®
, for example, are also deactiva-
ted.
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 affec-ted. The braking distance may increase in an emergency braking
situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Consult 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 trans-
mission, will be unavailable. Warning and indicator lamps in the instrument cluster
295On-board computer/Displays Z

Problem
Possible causes/consequences and
M
MSolutions !
The yellow ABS warning
lamp is lit while the
engine is running. ABS is temporarily unavailable. Therefore, BAS, COLLISION PRE-
VENTION ASSIST PLUS, ESP
®
, ESP ®
trailer stabilisation, EBD
(electronic brake force distribution), the HOLD function, hill start
assist, the adaptive brake lights and PRE ‑SAFE®
, for example, are
also deactivated.
Possible causes:
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, for example, if you brake hard.
The steerability and braking characteristics may be severely affec-ted. The braking distance may increase in an emergency braking
situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is a risk of an accident.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements at a speed above 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 Consult a qualified specialist workshop immediately. 296
Warning and indicator lamps in the instrument clusterOn-board computer/Displays