2012 MERCEDES-BENZ B-CLASS light

prevents the brakes from overheating and
wearing too quickly.
If a
slower-moving
vehicle is detected in front,
DISTRONIC PLUS brakes your vehicle. It
maintains the preset distance to the vehicle
in front.
If DISTRONIC PLUS detects that there is a risk
of a collision, you will be warned visually and
acoustically. DISTRONIC PLUS cannot
prevent a collision without your intervention.
An intermittent warning tone will then sound
and the distance warning lamp will light up in
the instrument cluster. Brake immediately in
order to increase the distance to the vehicle
in front or take evasive action provided it is
safe to do so.
For DISTRONIC PLUS to assist you when
driving, the radar sensor system must be:
R activated (Y page 199)
R operational
DISTRONIC PLUS is automatically
deactivated if:
R you are driving slower than 15 mph
(25 km/h) and there is no longer a vehicle
in front or
R the vehicle in front is no longer detected
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control in the speed range between 20 mph
(30 km/h) and 120 mph (200 km/h). If a
vehicle is driving in front of you, it operates in
the speed range between 0 mph (0 km/h) and
120 mph (200 km/h).
Do not use DISTRONIC PLUS while driving on
roads with steep gradients.
As DISTRONIC PLUS transmits radar waves,
it can resemble the radar detectors of the
responsible authorities. You can refer to the
relevant chapter in the Operator's Manual if
questions are asked about this.
i This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause harmful
interference, and 2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the
device will void any warranties, and is not
permitted. Do not
tamper with, alter, or use
in any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Cruise control lever :
To store the current speed or a higher
speed
; To store the current speed or a lower
speed
= To deactivate DISTRONIC PLUS
? To store the current speed or calling up
the last stored speed
A To set the specified minimum distance
Activating DISTRONIC PLUS; storing,
maintaining and calling up a speed Activation conditions
To activate DISTRONIC PLUS, all of the
following activation conditions must be
fulfilled:
R
the engine must

be started. It may take up
to two minutes after pulling away before
DISTRONIC PLUS is operational.
R the electric parking brake must be
released.
R ESP ®
must be active, but not intervening. Driving systems
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R
the transmission must be in position D.
R the driver's door
must be closed when you
shift from P to D or your seat belt must be
fastened.
R the front-passenger door and rear doors
must be closed.
R the vehicle must not skid.
Activating
To activate while driving: when driving at
speeds below 14 mph (20 km/h), you can
only activate DISTRONIC PLUS if the vehicle
in front has been detected and is shown in the
multifunction display. If the vehicle in front is
no longer detected and displayed,
DISTRONIC PLUS switches off and a tone
sounds.
X Briefly pull the cruise control level towards
you ?, or press it up : or down ;.
DISTRONIC PLUS is selected.
X Press the cruise control lever repeatedly
up : or down ; until the desired speed
is set.
X Remove your foot from the accelerator
pedal.
Your vehicle adapts

its speed to that of the
vehicle in front, but only up to the desired
stored speed.
i If you do

not fully release the accelerator
pedal, the DISTRONIC PLUS Passive
message appears in the multifunction
display. The set distance to a slower-
moving vehicle in front will then not be
maintained. You will be driving at the speed
you determine by the position of the
accelerator pedal.
To activate when driving towards a
stationary vehicle: if the vehicle in front is
stationary, you can only activate DISTRONIC
PLUS if your vehicle is also stationary.
X Briefly pull the cruise control level towards
you ?, or press it up : or down ;.
DISTRONIC PLUS is selected.
i DISTRONIC PLUS
can

only be activated at
under 14 mph (20 km/h) if a vehicle in front has been detected. It is therefore helpful to
have the
DISTRONIC

PLUS distance display
activated in the multifunction display
(Y page 194).
X Press the cruise control lever repeatedly
up : or down ; until the desired speed
is set.
i You can
use

the cruise control lever to set
the stored speed and the control on the
cruise control lever to set the specified
minimum distance (Y page 165). DISTRONIC PLUS displays in the speedometer
When DISTRONIC PLUS is activated, one or
two segments
;

in the set speed range light
up.
i For design reasons, the speed displayed
in the speedometer may differ slightly from
the speed set for DISTRONIC PLUS.
If DISTRONIC PLUS detects a vehicle in front,
segments ; between speed of the vehicle in
front : and stored speed = light up.162
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Distance display with DISTRONIC PLUS activated
in the multifunction display
:
DISTRONIC PLUS activated
; Own vehicle
= Specified minimum distance to the
vehicle in front; adjustable
? Vehicle in front, if detected
In the Assistance menu (Y page 194) of the
on-board computer, you can select the
distance display.
X Select the Distance Display function
using the on-board computer
(Y page 194).
i You will see the stored speed for about
five seconds
when
you activate DISTRONIC
PLUS.
Driving
If you depress the brake, DISTRONIC PLUS is
deactivated unless your vehicle is stationary.
Pulling away
X If the vehicle in front pulls away: remove
your foot from the brake pedal.
X Briefly pull the cruise control lever
(Y

page 161) towards you.
or
X Accelerate briefly.
Your vehicle pulls away and adapts its
speed to that of the vehicle in front.
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control.
If DISTRONIC PLUS detects that the vehicle
in front has slowed down, it brakes your vehicle. In this way, the distance you have
selected is maintained.
If DISTRONIC
PLUS

detects that there is a risk
of a collision, you will be warned visually and
acoustically. DISTRONIC PLUS cannot
prevent a collision without your intervention.
An intermittent warning tone will then sound
and the distance warning lamp will light up in
the instrument cluster. Brake immediately in
order to increase the distance from the
vehicle in front, or take evasive action,
provided it is safe to do so.
If DISTRONIC PLUS detects that the vehicle
in front is driving faster, it accelerates your
vehicle, but only up to the speed you have
stored.
Changing lanes
If you change to the passing lane, DISTRONIC
PLUS supports you when:
R you are driving faster than 40mph
(60 km/h)
R DISTRONIC PLUS is maintaining the
distance to a vehicle in front
R you switch on the appropriate turn signal
R DISTRONIC PLUS does not detect a danger
of collision
If these conditions are fulfilled, your vehicle
is accelerated. Acceleration will be
interrupted if changing lanes takes too long
or if the distance between your vehicle and
the vehicle in front becomes too small.
i When changing lanes, DISTRONIC PLUS
monitors the left lane on left-hand drive
vehicles and the right lane on right-hand
drive vehicles.
Stopping G
WARNING
When leaving the vehicle, even if it is braked
only by DISTRONIC

PLUS, it could roll away if:
R there is a malfunction in the system or in
the voltage supply.
R DISTRONIC PLUS has been deactivated
with the cruise control lever, e.g. by a Driving systems
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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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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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If you back up after activation, the steering
wheel is moved to the straight-ahead
position.
X Drive forwards or back up the vehicle, being
ready to brake at all times.
X Stop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
X Drive forwards and reverse as prompted by
the PARKTRONIC warning
displays, several
times if necessary.
Once you have exited the parking space
completely, the steering wheel is moved to
the straight-ahead position. You hear a tone
and the Park Assist Finished message
appears in the

multifunction display. You will
then have to steer and merge into traffic on
your own. PARKTRONIC is still available.
Canceling Active Parking Assist You can cancel Active Parking Assist at any
time.
X
Stop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at
once. The Park Assist Canceled
message appears in the multifunction
display.
or
X Press the PARKTRONIC button on the
center console (
Y

page 171).
PARKTRONIC is switched off and Active
Parking Assist is immediately canceled.
The Park Assist Canceled message
appears in the multifunction display.
Active Parking Assist is canceled
automatically if:
R you engage the electric parking brake.
R parking using Active Parking Assist is no
longer possible.
R you are driving faster than 6 mph
(10 km/h).
R a wheel

spins, ESP®
intervenes or fails. The
÷ warning lamp lights up in the
instrument cluster. A warning tone sounds. The parking space
symbol disappears and the multifunction
display shows the
Park Assist Canceled
message.
If Active
Parking

Assist is canceled, you must
steer again yourself.
If a system malfunction occurs, the vehicle is
braked to a standstill. To drive on, depress the
accelerator again. Rear view camera
Important safety notes The rear view camera is only an aid. It is not
a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering and
parking.
When
maneuvering

or parking, make
sure that there are no persons, animals or
objects in the area in which you are
maneuvering.
Under the following circumstances, the rear
view camera will not function, or will function
in a limited manner:
R the tailgate is open
R in heavy rain, snow or fog
R at night or in very dark places
R if the camera is exposed to very bright light
R if the area is lit by fluorescent light or LED
lighting (the display may flicker)
R if there is a sudden change in temperature,
e.g. when driving into a heated garage in
winter
R if the camera lens is dirty or obstructed
R if the rear of your vehicle is damaged. In
this event, have the camera position and
setting checked at a qualified specialist
workshop.176
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