2012 MERCEDES-BENZ B-CLASS automatic transmission

to lose traction and the vehicle could then
skid
R when there is
poor visibility, e.g. due to fog,
heavy rain or snow
If there is a change of drivers, advise the new
driver of the speed stored.
General notes Cruise control maintains a constant road
speed for
you.

It brakes automatically in order
to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden, you must select a low gear in
good time. For this, you will need to have
selected manual drive program
M(Y page 144). By doing so, you will make
use of the braking effect of the engine, This
relieves the load on the brake system and
prevents the brakes from overheating and
wearing too quickly.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can
store any road speed above 20 mph
(30 km/h).
Cruise control lever :
To activate or increase speed
; To activate or reduce speed
= To deactivate cruise control
? To activate at the current speed/last
stored speed When you activate cruise control, the stored
speed is shown in the multifunction display
for five seconds.
Activation conditions
To activate cruise control, all of the following
activation conditions must be fulfilled:
R
the electric parking brake must be
released.
R you are driving faster than
20 mph(30 km/h).
R ESP ®
must be active, but not intervening.
R on vehicles with automatic transmission,
the selector lever must be in position D.
Storing, maintaining and calling up a
speed Storing and maintaining the current
speed
You can store the current speed if you are
driving faster than 20 mph (30km/h).
X
Accelerate the vehicle to the desired
speed.
X Briefly press the cruise control lever
up : or down ;.
X Remove your foot from the accelerator
pedal.
Cruise control is activated. The vehicle
automatically maintains the stored speed.
i Cruise control may

be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient
evens out. Cruise control maintains the
stored speed on downhill gradients by
automatically applying the brakes.
Storing the current speed or calling up the
last stored speed G
WARNING
If you call up the stored speed and it differs
from the current speed, the vehicle
accelerates or decelerates.

If you do not know
the stored speed, the vehicle could accelerate 158
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or brake unexpectedly. There is a risk of an
accident.
Pay attention to the road and traffic
conditions before
calling
up the stored speed.
If you do not know the stored speed, store the
desired speed again.
X Briefly pull the cruise control lever towards
you ?.
X Remove your foot from the accelerator
pedal.
The first time cruise control is activated, it
stores the current speed or regulates the
speed of the vehicle to the previously
stored speed.
Setting a speed Keep in mind that it may take a brief moment
until
the
vehicle

has accelerated or braked to
the speed set.
X Press the cruise control lever up : for a
higher speed or

down ; for a lower speed.
X To adjust the set speed in 1 mph
increments (1
km/h

increments): briefly
press the cruise control lever up : or
down ; to the pressure point.
Every time the cruise control lever is
pressed up : or down ; the last speed
stored is increased or reduced.
X To adjust the set speed in 5 mph
increments (10 km/h increments):
briefly press the cruise control lever
up : or down ; to the pressure point.
Every time the cruise control lever is
pressed up : or down ; the last speed
stored is increased or reduced.
i Cruise control is not deactivated if you
depress the accelerator pedal. For
example, if you accelerate briefly to
overtake, cruise control adjusts the
vehicle's speed to the last speed stored
after you have finished overtaking. Deactivating cruise control There are several ways to deactivate cruise
control:
X
Briefly press the cruise control lever
forwards =.
or
X Brake.
Cruise control is automatically deactivated if:
R you engage the electric parking brake.
R you are driving at less than 20 mph
(30 km/h ).
R ESP ®
intervenes or you deactivate ESP ®
.
R you shift the transmission to position

N
while driving.
If cruise control is deactivated, you will hear
a warning tone. You will see the Cruise
Control Off message in the multifunction
display for approximately five seconds.
i When you switch off the engine, the last
speed stored is cleared. DISTRONIC PLUS
Important safety notes G
WARNING
DISTRONIC PLUS does not react to:
R people or animals
R stationary obstacles on the road, e.g.
stopped or parked vehicles
R oncoming and crossing traffic
As a result,

DISTRONIC PLUS may neither give
warnings nor intervene in such situations.
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. G
WARNING
DISTRONIC PLUS cannot always clearly
identify other road users and complex traffic
situations. Driving systems
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vehicle occupant or from outside the
vehicle.
R the electrical system in the engine
compartment, the battery
or the fuses have
been tampered with.
R the battery is disconnected.
R the accelerator pedal has been depressed,
e.g. by a vehicle occupant.
There is a risk of an accident.
If you wish to exit the vehicle, always turn off
DISTRONIC PLUS and secure the vehicle
against rolling away.
Deactivating DISTRONIC PLUS
(Y page 165).
If DISTRONIC PLUS detects that the vehicle
in front is stopping, it brakes your vehicle until
it is stationary.
Once your vehicle is stationary, it remains
stationary and you do not need to depress the
brake.
i After a time, the electric parking brake
secures the vehicle and relieves the service
brake.
i Depending on the specified minimum
distance, your vehicle will come to a
standstill at a sufficient distance behind the
vehicle in front. The specified minimum
distance is set using the control on the
cruise control lever.
The electric parking brake automatically
secures the vehicle if DISTRONIC PLUS 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.Storing the current speed or calling up the
last stored speed G
WARNING
If you call up the stored speed and it differs
from the current speed, the vehicle
accelerates or decelerates.

If you do not know
the stored speed, the vehicle could accelerate
or brake unexpectedly. There is a risk of an
accident.
Pay attention to the road and traffic
conditions before calling up the stored speed.
If you do not know the stored speed, store the
desired speed again.
X Briefly pull the cruise control lever
(Y page 161) towards you.
X Remove your foot from the accelerator
pedal.
DISTRONIC PLUS is activated. The first
time it is activated, the current speed is
stored. Otherwise, it

sets the vehicle cruise
speed to the previously stored value.
Setting a speed Keep in mind that it may take a brief moment
until the
vehicle

has accelerated or braked to
the speed set. :
To store the current speed or a higher
speed
; To store the current speed or a lower
speed164
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i
The last speed
stored remains stored until
you switch off the engine.
DISTRONIC PLUS is automatically
deactivated if:
R you engage the electric parking brake or if
the vehicle is automatically secured with
the electric parking brake
R you are driving slower than 7 mph
(10km/h) and there is no vehicle in front,
or if the vehicle in front is no longer
detected
R ESP ®
intervenes or you deactivate ESP ®
R the transmission is in the P, R or N position
R you pull the cruise control lever towards
you in order to pull away and the front-
passenger door or one of the rear doors is
open
R the vehicle has skidded
If DISTRONIC PLUS is deactivated, you will
hear a warning tone. You will see the
DISTRONIC PLUS Off message in the
multifunction display for approximately five
seconds.
In the Assistance menu (Y page 194) of the
on-board computer, you can select the
distance display. Distance display when DISTRONIC PLUS is
deactivated
:
Vehicle in front, if detected
; Distance indicator, current distance to
the vehicle in front
= Specified minimum distance to the
vehicle in front; adjustable
? Own vehicle X
Select the Distance Display function
using the on-board computer
(Y page 194).
Tips for driving with DISTRONIC PLUS General notes
The following
contains

descriptions of certain
road and traffic conditions in which you must
be particularly attentive. In such situations,
brake if necessary. DISTRONIC PLUS is then
deactivated.
Cornering, going into and coming out of a
bend The ability of DISTRONIC PLUS to detect
vehicles when cornering is limited. Your
vehicle may brake unexpectedly or late.
Vehicles traveling on a different line
DISTRONIC PLUS may not detect vehicles
traveling on a different line. The distance to
the vehicle in front will be too short.166
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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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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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