brake MERCEDES-BENZ B-CLASS HATCHBACK 2014 Repair Manual

X
To cancel the procedure: press the%
button on the multifunction steering wheel or pull away.
or
X To park using Active Parking Assist:
press the abutton on the multifunction
steering wheel.
The Park Assist active Accelerate
Park Assist active Accelerate
and brake and brake Observe surroundings
Observe surroundings mes-
sage appears in the multifunction display.
X Release the multifunction steering wheel.
X Reverse the vehicle, being ready to brake at
all times. When reversing, drive at a speed
below 10 km/h. Otherwise, Active Parking Assist will be cancelled.
Vehicles with automatic transmission:
Active Parking Assist brakes the vehicle to a standstill when the vehicle approaches
the rear border of the parking space.
Manoeuvring may be required in tight park-
ing spaces.
X Vehicles with manual transmission:
stop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
Manoeuvring may be required in tight park-
ing spaces.
Vehicles with automatic transmission: the
Park Assist active Select D
Park Assist active Select D Observe Observe
surroundings
surroundings message appears in the mul-
tifunction display.
Vehicles with manual transmission: the
Park Assist active Engage forward
Park Assist active Engage forward
gear
gear Observe surroundings Observe surroundings message
appears in the multifunction display.
X Vehicles with manual transmission:
shift to first gear while the vehicle is sta-
tionary.
Vehicles with automatic transmission:
select transmission position Dwhile the
vehicle is stationary.
Active Parking Assist immediately steers in
the other direction. The
Park Assist active Accelerate
Park Assist active Accelerate
and brake and brake Observe surroundings
Observe surroundings mes-
sage appears in the multifunction display.
i You will achieve the best results by wait-
ing for the steering procedure to complete before pulling away.
X Drive forwards and be ready to brake at all
times.
Vehicles with automatic transmission:
Active Parking Assist brakes the vehicle to a standstill when the vehicle approaches
the front border of the parking space.
Manoeuvring may be required in tight park-
ing spaces.
X Vehicles with manual transmission:
stop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
Vehicles with automatic transmission: the
Park Assist active Select R
Park Assist active Select R Observe Observe
surroundings
surroundings message appears in the mul-
tifunction display.
Vehicles with manual transmission: the
Park Assist active Engage reverse Park Assist active Engage reverse
gear gear Observe surroundings
Observe surroundings message
appears in the multifunction display.
As soon as the parking procedure is com-
plete, the Park ParkAssist
Assist switched
switched off
offmes-
sage appears and a warning tone sounds. The
vehicle is now parked.
Vehicles with automatic transmission: the
vehicle is kept stationary without the driver
having to depress the brake pedal. The brak-
ing effect is cancelled when you depress the
accelerator pedal.
Active Parking Assist no longer supports you
with steering interventions and brake appli-
cations. When Active Parking Assist is fin-
ished, you must steer and brake again your-
self. PARKTRONIC is still available.
Parking tips:
R The way your vehicle is positioned in the
parking space after parking is dependent
on various factors. These include the posi-
tion and shape of the vehicles parked in
front and behind it and the conditions of the Driving systems
209Driving and parking Z

location. It may be the case that Active
Parking Assist guides you too far into a
parking space, or not far enough into it. In
some cases, it may also lead you across or
onto the kerb. If necessary, you should can-
cel the parking procedure with Active Park- ing Assist.
R You can also preselect transmission posi-
tion D. The vehicle redirects and does not
drive as far into the parking space. Should
the transmission change take place too
early, the parking procedure will be cancel- led. A sensible parking position can no lon-
ger be achieved from this position.
Exiting a parking space In order that Active Parking Assist can sup-
port when exiting the parking space:
R you need to have parked using Active Park-
ing Assist.
R the border of the parking space must be
high enough at the front and the rear. A
kerb stone is too small, for example.
R the border of the parking space must not be
too wide, as the position of the vehicle must
not exceed an angle of 45° to the starting
position as it is manoeuvred into the park-
ing space.
R a manoeuvring distance of at least 1.0 m
must be available.
Active Parking Assist can only assist you with exiting a parking space if you have parked thevehicle parallel to the direction of travel using
Active Parking Assist.
i Vehicles with automatic transmission:
If PARKTRONIC detects obstacles, Active
Parking Assist brakes automatically whilst
the vehicle exits the parking space. You are
responsible for braking in good time.
X Start the engine.
X Release the electric parking brake.
X Switch on the turn signal in the direction
you are pulling away. X
Vehicles with automatic transmission:
shift the transmission to position Dor R.
Vehicles with manual transmission:
shift to forward or reverse gear.
The Start Park Assist? Yes: OK No:
Start Park Assist? Yes: OK No:
message appears in the multifunction dis-
play %.
X To cancel the procedure: press the%
button on the multifunction steering wheel
or pull away.
or
X To exit a parking space using Active
Parking Assist: press theabutton on
the multifunction steering wheel.
The Park Assist active Accelerate Park Assist active Accelerate
and
and brake
brake Observe
Observe surroundings
surroundings mes-
sage appears in the multifunction display.
X Release the multifunction steering wheel.
X Pull away, being ready to brake at all times.
Do not exceed a maximum speed of
approximately 10 km/h when exiting a
parking space. Otherwise, Active Parking
Assist will be cancelled.
X Vehicles with manual transmission:
stop, at the latest when PARKTRONIC
sounds the continuous warning tone.
X Vehicles with automatic transmission:
depending on the message or as required,
shift the transmission to position Dor R.
Vehicles with manual transmission:
depending on the message or as required,
engage forward or reverse gear.
Active Parking Assist immediately steers in
the other direction. The Park Assist Park Assist
active Accelerate and brake
active Accelerate and brake
Observe Observe surroundings
surroundings message appears
in the multifunction display.
i You will achieve the best results by wait-
ing for the steering procedure to complete before pulling away.
If you reverse after activation, the steering
wheel is moved to the straight-ahead posi- tion. 210
Driving systemsDriving and parking

X
Drive forwards and reverse as prompted by
the PARKTRONIC warning displays, several
times if necessary.
X Vehicles with manual transmission:
stop, at the latest when PARKTRONIC
sounds the continuous warning tone.
Once you have exited the parking space com- pletely, the steering wheel is moved to the
straight-ahead position. You hear a tone and
the Park Assist switched off Park Assist switched off message
appears in the multifunction display. You will
then have to steer and merge into traffic on
your own. PARKTRONIC is still available. You
can take over the steering before the vehicle has exited the parking space completely. This
is useful, for example when you recognise
that it is already possible to pull out of the
parking space.
Cancelling Active Parking Assist X
Stop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be immediately
cancelled. The Park Assist cancelled Park Assist cancelled
message appears in the multifunction dis-
play.
or
X Press the PARKTRONIC button
(Y page 205).
PARKTRONIC is switched off and Active
Parking Assist is immediately cancelled.
The Park Assist cancelled Park Assist cancelled message
appears in the multifunction display.
Active Parking Assist is cancelled automati-
cally if:
R the electric parking brake is applied
R transmission position Pis selected in vehi-
cles with automatic transmission
R parking using Active Parking Assist is no
longer possible
R you are driving faster than 10 km/h
R a wheel spins and ESP ®
intervenes or fails.
The ÷ warning lamp lights up in the
instrument cluster. A warning tone sounds. The parking symbol
disappears and the multifunction display
shows the
Park Assist cancelled
Park Assist cancelled mes-
sage.
When Active Parking Assist is cancelled, you
must steer and brake again yourself.
If a system malfunction occurs, the vehicle is braked to a standstill. To drive on, depress the
accelerator pedal again. Reversing camera
General notes Reversing camera
:is an optical parking
and manoeuvring aid. It uses guide lines to
show the area behind your vehicle in the
Audio/COMAND display.
The area behind the vehicle is displayed as a
mirror image, as in the rear-view mirror.
i The text shown in the Audio/COMAND
display depends on the language setting.
The following are examples of reversing
camera displays in the Audio/COMAND
display.
See the notes on cleaning (Y page 328).
Important safety notes The reversing camera is only an aid. It is not a
substitute for your attention to the immediate surroundings. 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. Driving systems
211Driving and parking Z

Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in
front of your vehicle by means of camera :
at the top of the windscreen. Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally.
This function is available within a speed range between 60 km/h and 200 km/h.
A warning may be given if a front wheel
passes over a lane marking. It will warn you by
means of intermittent vibration through the
steering wheel for up to 1.5 seconds.
Important safety notes G
WARNING
Lane Keeping Assist cannot always clearly
identify lane markings.
In these cases, Lane Keeping Assist may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep in lane, especially if Lane
Keeping Assist alerts you. G
WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is a risk of an accident. Always steer, apply the brakes or accelerate
the vehicle yourself, especially if Lane Keep-
ing Assist alerts you.
If you fail to adapt your driving style, Lane
Keeping Assist can neither reduce the risk of
an accident nor override the laws of physics.
Lane Keeping Assist cannot take into account road, weather or traffic conditions. Lane
Keeping Assist is only an aid. You are respon-
sible for the distance to the vehicle in front,
for vehicle speed, for braking in good time,
and for staying in lane.
Lane Keeping Assist does not keep your vehi- cle in its lane.
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 Driving systems
223Driving and parking Z

Activating Lane Keeping Assist
X Activate Lane Keeping Assist using the on-
board computer; to do so, select Standard
Standard
or Adaptive
Adaptive (Ypage 245).
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 243) are shown in green.
When Standard
Standard is selected, no warning vibra-
tion occurs if:
R you have switched on the turn signals. 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 signals. In
this case, 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 the permissible load for a car- rier system is exceeded, the carrier could
come loose from the vehicle and endanger
other road users. There is a risk of an accidentand injury.
Never exceed the permissible noseweight
when using a carrier.
Exceeding the maximum permissible nose-
weight of the trailer drawbar on the ball cou-
pling may cause damage to the following: R your vehicle
R the trailer
R the ball coupling
R trailer tow hitch
The vehicle/trailer combination could
become unstable.
If the noseweight used is lower than the min- imum permissible noseweight, the vehicle/
trailer combination could also become unsta-ble.
To avoid hazardous situations:
R make sure to check the noseweight before
each journey
R use a drawbar noseweight as close as pos-
sible to the maximum noseweight 224
Towing a trailerDriving and pa
rking

The maximum permissible speed for vehicle/
trailer combinations depends on the type of
trailer. Before beginning the journey, check
the trailer's documents to see what the max- imum permitted speed is. Observe the legally
prescribed maximum speed in the relevant
country.
For certain Mercedes-Benz vehicles, the max-
imum permissible rear axle load is increased
when towing a trailer. See the "Technical
data" section to find out whether this applies to your vehicle. If you utilise any of the added
maximum rear axle load when towing a trailer, the vehicle/trailer combination may not
exceed a maximum speed of 100 km/h for
reasons concerning the operating permit.
This also applies in countries in which the
permissible maximum speed for vehicle/
trailer combinations is above 100 km/h.
When towing a trailer, your vehicle's handling
characteristics will be different in comparison to when driving without a trailer and it will
consume more fuel.
Change into a lower gear in good time on long
and steep downhill gradients. For vehicles
with automatic transmission, you need to
have selected manual drive program M
(Y page 175).
This also applies if you have activated cruise
control, SPEEDTRONIC or DISTRONIC PLUS.
This will use the braking effect of the engine,
so less braking will be required to maintain
vehicle speed. This relieves the load on the
brake system and prevents the brakes from
overheating and wearing too quickly. If you
need additional braking, depress the brake
pedal repeatedly rather than continuously.
Briefly depressing the accelerator pedal on
downhill gradients while the manual drive
program Mis temporarily activated (vehicles
with automatic transmission): the automatic
transmission may switch back to the last
active automatic drive program Eor S. The
automatic transmission may shift to a higher
gear. This can reduce the engine's braking
effect. Driving tips If the trailer swings from side to side:
X Do not accelerate.
X Do not countersteer.
X Brake if necessary.
R Maintain a greater distance to the vehicle in
front than when driving without a trailer.
R Avoid braking abruptly. If possible, brake
gently at first to allow the trailer to run on.
Then, increase the braking force rapidly.
R The values given for gradient-climbing
capabilities from a standstill refer to sea
level. When driving in mountainous areas,
note that the power output of the engine,
and consequently the vehicle's gradient-
climbing capability, decrease with increas-
ing altitude. Folding out the ball coupling
G
WARNING
If the ball coupling is not correctly engaged,
the trailer can detach. There is a risk of an
accident.
Always engage the ball coupling as described. G
WARNING
If you release the ball coupling or it does not
engage correctly when folding in, it will swing out. Within pivoting range of the ball coupling,
there is an increased risk of an accident and
injury.
Only release the ball coupling if the pivoting
range is unobstructed. Always make sure that the ball coupling engages when folding in.
Before you can tow a trailer with your vehicle, you must fold out the ball coupling.
The release wheel is located behind the left-
hand side trim panel in the boot. 226
Towing a trailerDriving and parking

X
To open the cover: turn handle:anti-
clockwise, the fold down and remove
cover ;. X
Pull out release wheel =.
X Turn release wheel =anti-clockwise as far
as it will go.
The ball coupling disengages and folds out
behind the rear bumper. Indicator lamp ?
flashes. X
Pull the ball coupling in the direction of the
arrow until it engages in a vertical position.
The indicator lamp on the release wheel
goes out. The power socket folds down
automatically.
The multifunction display shows the
Check Check trailer
trailer hitch
hitchlock
lockdisplay mes-
sage until the ball coupling is engaged.
X Remove the protective covering from the
ball coupling and store it in a safe place.
X Make sure that the ball of the ball coupling
is clean and that it is either greased or dry
(grease free), depending on the instruc-
tions for the trailer. Coupling up a trailer
X Make sure that the transmission is in posi-
tion P.
X Apply the electric parking brake.
X Position the trailer horizontally behind the
vehicle.
X Couple up the trailer.
X Establish the electric connection between
the vehicle and the trailer.
X Check that the trailer lighting system is
working.
A connected trailer is only recognised when
the electrical connection is established
correctly and when the lighting system is
working properly. The function of other sys-
tems, such as ESP ®
or PARKTRONIC also
depends on this. Uncoupling a trailer
G
WARNING
If you uncouple a trailer with an engaged over- run brake, you could trap your hand between
the vehicle and the trailer drawbar. This poses a risk of injury.
Do not uncouple a trailer with an engaged
overrun brake. Towing a trailer
227Driving and parking Z

!
Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the rebound- ing of the overrun brake.
! Remove the installed adapter cable
before folding in the ball coupling. Other-
wise, damage may occur to the rear
bumper and the adapter cable.
X Make sure that the transmission is in posi-
tion P.
X Apply the electric parking brake.
X Secure the trailer against rolling away.
X Remove the trailer cable and decouple the
trailer. Folding in the ball coupling
G
WARNING
If you release the ball coupling or it does not
engage correctly when folding in, it will swing out. Within pivoting range of the ball coupling,
there is an increased risk of an accident and
injury.
Only release the ball coupling if the pivoting
range is unobstructed. Always make sure that the ball coupling engages when folding in.
Fold the ball coupling back in if you are not
using the trailer tow hitch.
The release wheel is located behind the left-
hand side trim panel in the boot.
X Place the protective covering on the ball
coupling. X
To open the cover: turn handle:anti-
clockwise, then fold down and remove
cover ;. X
Pull out release wheel =.
X Turn release wheel =anti-clockwise as far
as it will go.
The ball coupling disengages and folds in
behind the rear bumper. Indicator lamp ?
flashes. X
Press the ball coupling in the direction of
the arrow until it engages behind the
bumper.
The indicator lamp on the release knob and
the message in the multifunction display go
out. Trailer power supply
! You can connect accessories with a
power rating of up to 240 W to the perma-
nent power supply and with a power rating of up to 180 W to the power supply that is
switched on via the ignition lock. 228
Towing a trailerDriving and parking

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 display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. !÷
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 252
Display messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions 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 Drive on carefully.
X Visit a qualified specialist workshop immediately. ÷
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual ESP
®
, ESP ®
trailer stabilisation, BAS, the HOLD function, hill start
assist and PRE-SAFE ®
are temporarily unavailable.
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.
The self-diagnosis function, for example, may not be complete.
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 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 display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. Display
messages
253On-board computer and displays Z