2012 MERCEDES-BENZ B-CLASS Owners Manual

Other vehicles changing lanes
DISTRONIC PLUS has not detected the
vehicle cutting in yet. The distance to this
vehicle will be too short.
Narrow vehicles
DISTRONIC PLUS has not yet detected the
vehicle in front on the edge of the road,
because of its narrow width. The distance to
the vehicle in front will be too short.
Obstructions and stationary vehicles
DISTRONIC PLUS does not brake for
obstacles or stationary vehicles. If, for example, the detected vehicle turns a corner
and reveals
an
obstacle or stationary vehicle,
DISTRONIC PLUS will not brake for these.
Crossing vehicles DISTRONIC PLUS may detect vehicles that
are crossing
your

lane by mistake. Activating
DISTRONIC PLUS at traffic lights with
crossing traffic, for example, could cause
your vehicle to pull away unintentionally. HOLD function
Important safety notes G
WARNING
When leaving the vehicle, it can still roll away
despite being braked

by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply.
R the HOLD function has been deactivated by
pressing the accelerator pedal or the brake
pedal, e.g. by a vehicle occupant.
R the electrical system in the engine
compartment, the battery or the fuses have
been tampered with.
R the battery is disconnected
There is a risk of an accident.
If you wish to exit the vehicle, always turn off
the HOLD function and secure the vehicle
against rolling away. Driving systems
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!
If DISTRONIC PLUS
or the HOLD function
is activated, the vehicle brakes
automatically in certain situations. To
prevent damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or other similar situations:
R when towing the vehicle
R in the car wash
Deactivate the HOLD function (Y page 168).
General notes The HOLD function can assist the driver in the
following situations:
R
when pulling away, especially on steep
slopes
R when maneuvering on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect

is canceled and the HOLD
function deactivated when you depress the
accelerator pedal to pull away.
Activation conditions You can activate the HOLD function if:
R
the vehicle is stationary
R the engine is running or if it has been
automatically switched off by the ECO
start/stop function
R the driver's
door

is closed or your seat belt
is fastened
R the electric parking brake is released
R the transmission position D, R or N is
engaged while driving a vehicle with an
automatic transmission
R DISTRONIC PLUS is deactivated Activating the HOLD function X
Make sure that the activation conditions
are met.
X Depress the brake pedal.
X Quickly depress the brake pedal further
until : appears in the multifunction
display.
The HOLD function is activated. You can
release the brake pedal.
i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.
Deactivating the HOLD function The HOLD function is deactivated
automatically if:
R
you accelerate. On

vehicles with automatic
transmission: only when the transmission
is in position D or R.
R the transmission is in position P on vehicles
with automatic transmission.
R you depress the brake pedal again with a
certain amount of pressure until :
disappears from the multifunction display.
R you secure the vehicle using the electric
parking brake.
R you activate DISTRONIC PLUS.
i After a time, the electric parking brake
secures the vehicle and relieves the service
brake. 168
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The electronic parking brake secures the
vehicle automatically if the HOLD function is
activated and:
R
the driver's door is open and the driver's
seat belt is unfastened.
R the engine is switched off, unless it is
automatically switched off by the ECO
start/stop function.
R a system malfunction occurs.
R the power supply is not sufficient.
If a malfunction
occurs, then the transmission
may be shifted into position P automatically.PARKTRONIC
Important safety notes 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 maneuvering.
!
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 other
objects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic
car wash, the compressed-air brakes on a
truck or a pneumatic drill could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It indicates visually and
audibly the distance between your vehicle
and an object. PARKTRONIC is activated automatically when
you:
R
switch on the ignition
R shift the transmission

to position D, R or N
R release the electric parking brake
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h). It is reactivated at lower
speeds.
PARKTRONIC monitors the area around your
vehicle using six sensors in the front bumper
and four sensors in the rear bumper.
Range of the sensors General notes
PARKTRONIC does not take objects into
consideration that are:
R
below the detection range, e.g. people,
animals or objects
R above the detection range, e.g.
overhanging loads, truck overhangs or
loading ramps. :
Sensors in the front bumper, left-hand
side (example) Side view Driving systems
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Top view
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 275).
Front sensors Center Approx. 40in (approx.
100cm)
Corners Approx. 24in (approx.
60cm)
Rear sensors
Center Approx. 48 in (approx.
120 cm)
Corners Approx. 32in (approx.
80cm)
Minimum distance
Center Approx. 8in (approx. 20cm)
Corners Approx. 8in (approx. 20cm)
If there is an obstacle within this range, the
relevant warning displays light up and a
warning tone sounds. If the distance falls
below the minimum, the distance may no
longer be shown.
Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located on the dashboard above the center air vents.
The warning display for the rear area is
located on the headliner in the rear
compartment.
Warning display for the front area
:
Segments on the left-hand side of the
vehicle
; Segments on the right-hand side of the
vehicle
= Segments showing operational readiness
The warning display for each side of the
vehicle is divided

into five yellow and two red
segments. PARKTRONIC is operational if
yellow segments showing operational
readiness = light up.
The selected transmission position and the
direction in which the vehicle is rolling
determine which warning display is active
when the engine is running. Transmission
position Warning display
D
Front area activated
R, N or the vehicle
is rolling
backwards Rear and front areas
activated
P
No areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.170
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From the:
R
sixth segment onwards, you will hear an
intermittent warning tone for
approximately two seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two
seconds. This indicates that you have now
reached the minimum distance.
Deactivating/activating PARKTRONIC :
Indicator lamp
; To deactivate/activate PARKTRONIC
If indicator lamp : lights
up, PARKTRONIC is
deactivated.
i PARKTRONIC is automatically activated
when you turn the SmartKey to position 2
in the ignition lock. Driving systems
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Problems with PARKTRONIC
Problem Possible causes/consequences and
M SolutionsOnly the red segments
in the PARKTRONIC
warning displays
are
lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is
deactivated after
approximately
20 seconds, and the
indicator lamp in the
PARKTRONIC button
lights up. PARKTRONIC has malfunctioned and has switched off.
X
If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. Only the red segments
in the PARKTRONIC
warning displays
are

lit.
PARKTRONIC is
deactivated after
approximately
20seconds. The PARKTRONIC sensors are dirty or there is interference.
X
Clean the PARKTRONIC sensors ( Y page 275).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves.
X
See if PARKTRONIC functions in a different location. Active Parking Assist
Important safety notes Active Parking Assist is merely 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 maneuvering.
G
WARNING
The vehicle swings out when parking and in
doing so could cross into the opposite lane.
This could result in a collision with another
road user. There is a risk of an accident.
Pay attention to other road users when
parking. Stop the vehicle if necessary or cancel the Active Parking Assist parking
procedure.
! If unavoidable, you should drive over
obstacles such as curbs slowly and not at
a sharp angle.

Otherwise, you may damage
the wheels or tires.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for
parking, for example:
R where parking or stopping is prohibited
R in front of driveways or entrances and exits
R on unsuitable surfaces
Parking tips:
R On narrow roads, drive as close to the
parking space as possible.
R Parking spaces that are littered, overgrown
or partially occupied by trailer drawbars
might be identified incorrectly or not at all.172
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R
Snowfall or heavy
rain may lead to a parking
space being measured inaccurately.
R Pay attention to the PARKTRONIC
(Y page 170) warning messages during the
parking procedure.
R You can intervene in the steering procedure
to correct it at any time. Active Parking
Assist will then be canceled.
R When transporting a load which protrudes
from your vehicle, you should not use
Active Parking Assist.
R Never use Active Parking Assist when snow
chains are installed.
R Make sure that the tire pressures are
always correct. This has a direct influence
on the parking characteristics of the
vehicle.
General notes Active Parking Assist is an electronic parking
aid with ultrasound. Ultrasound is used to
measure the
road

on both sides of the vehicle.
A suitable parking space is indicated by the
parking symbol. Active steering intervention
can assist you during parking.
You may also use PARKTRONIC
(Y page 169). When PARKTRONIC is switched
off, Active Parking Assist is also unavailable.
Use Active Parking Assist for parking spaces:
R that are parallel to the direction of travel
R that are on straight roads, not bends
R that are on the same level as the road, e.g.
not on the pavement
Detecting parking spaces Objects located above the height range of
Active Parking Assist will not be detected
when the parking space is measured. These
are not taken into account when the parking
procedure is calculated, e.g. overhanging
loads,
tail
sections

or loading ramps of goods
vehicles. In some circumstances, Active
Parking Assist may therefore guide you into
the parking space too early. G
WARNING
If there are objects above the detection range,
Active Parking Assist may turn prematurely.
You may cause

a collision as a result. There is
a risk of an accident.
If there are objects above the detection range,
stop and deactivate Active Parking Assist.
Active Parking Assist is automatically
activated when driving forwards. The system
is operational at speeds of up to
approximately 22 mph (35 km/h). While in
operation, the system independently locates
and measures parking spaces on both sides
of the vehicle. When driving at speeds below
19 mph (30 km/h), you will see the parking
symbol as a status indicator in the instrument
cluster. By default, Active Parking Assist only
displays parking spaces on the front-
passenger side. Parking spaces on the
driver's side are displayed as soon as the turn
signal on the driver's side is activated. To park
on the driver's side, you must leave the
driver's side turn signal switched on. This
must remain switched on until you
acknowledge the use of Active Parking Assist
by pressing the a button on the
multifunction steering wheel.
When a parking space has been detected, an
arrow towards the right or the left also
appears. Example: detected parking space for a vehicle with
automatic transmission
:
Detected parking space on the left
; Parking symbol
= Detected parking space on the right Driving systems
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Active Parking Assist will only detect parking
spaces:
R
that are parallel to the direction of travel
R that are at least 59 in (1.5 m) wide
R that are at least 51 in (1.3 m) longer than
your vehicle
A parking space is displayed while you are
driving past it, and until you are
approximately 50 ft (15 m) away from it.
Parking G
WARNING
Active Parking Assist merely aids you by
intervening actively in the steering. If you do
not brake there is a risk of an accident.
Always apply the brakes yourself when
maneuvering and parking.
i When PARKTRONIC detects obstacles,
Active Parking Assist brakes automatically
during the parking process. You are
responsible for braking in good time.
Active Parking Assist does not support you
with parking spaces parallel to the direction
of travel if:
R the parking space is on a curb
R the parking space is apparently blocked,
for example by foliage or grass paving
blocks
R the range of movement is too small
R the parking space is bordered by an
obstacle which is not clearly defined such
as a tree or a trailer
X Stop the vehicle when the parking space
symbol shows the
desired parking space in
the instrument cluster.
X Shift the transmission to position R.
The Start Park Assist? Yes: OK No:
% message appears

in the multifunction
display. 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 a

button on the multifunction
steering wheel.
The Park Assist Active Accelerate
and Brake Observe Surroundings
message appears in the multifunction
display.
X Let go of the multifunction steering wheel.
X Back up the vehicle, being ready to brake
at all times. Do not exceed a maximum
speed of approximately 5 mph (10 km/h )
when

backing up. Otherwise Active Parking
Assist will be canceled.
i In tight parking spaces, you will achieve
the best parking results by backing up as
far as possible. When doing so, also
observe the PARKTRONIC messages.
X Stop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
Maneuvering may be required in tight
parking spaces.
The Park Assist Active Select D
Observe Surroundings

message appears in
the multifunction display.
X Shift the transmission to position D while
the vehicle is stationary.
Active Parking Assist

immediately steers in
the other direction.
The Park Assist Active Accelerate
and Brake Observe Surroundings
message appears in the multifunction
display.
i You will achieve the best results by
waiting for the steering procedure to
complete before pulling away.
X Drive forwards and be ready to brake at all
times.
X Stop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.174
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