brake light MERCEDES-BENZ B-CLASS 2012 Owner's Manual

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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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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Driving and parking
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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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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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At speeds above 20 mph (30 km/h) the
indicator lamp
goes
out and Blind Spot Assist
is operational.
If a vehicle is detected within the monitoring
range of Blind Spot Assist at speeds above
20 mph (30 km/h), warning lamp : on the
corresponding side lights up red. This warning
is always emitted when a vehicle enters the
blind spot monitoring range from behind or
from the side. When you overtake a vehicle,
the warning only occurs if the difference in
speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Blind Spot
Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the
corresponding turn signal, a double warning
tone sounds. Red warning lamp : flashes. If
the turn signal remains on, vehicles detected
are indicated by the flashing of red warning
lamp :. There are no further warning tones.
Switching on Blind Spot Assist
X Make sure that the radar sensor system
(Y page 199) and Blind Spot Assist
(Y page 195)
are

activated in the on-board
computer.
X Turn the SmartKey to position 2 in the
ignition lock.
Warning lamps : in the exterior mirrors
light up red for approximately
1.5 seconds and then turn yellow.
Lane Keeping Assist General notes
Lane Keeping Assist monitors the area in
front of
your

vehicle by means of a camera at
the top of the windshield. Lane Keeping Assist
detects lane markings on the road and warns you before you leave your lane
unintentionally.
:
Lane Keeping Assist camera
If you select km on the on-board computer in
the Display Unit Speed-/Odometer:
function ( Y page 196), Lane Keeping Assist
is active starting

at a speed of 60 km/h. If the
miles display unit is selected, the assistance
range begins at 40 mph.
Important safety notes G
WARNING
Lane Keeping Assist may not always clearly
recognize lane markings.
In this case, 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 stay in lane, in particular if
warned by Lane Keeping Assist. G
WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There
is a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane
Keeping Assist.
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
the road, traffic and weather conditions. Lane Driving systems
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Driving and parking Z
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Keeping Assist is merely an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
The Lane Keeping Assist does not keep the
vehicle in the lane.
The system may be impaired or may not
function if:
R
there is poor visibility, e.g. due to
insufficient illumination of
the road, or due
to snow, rain, fog or spray
R there is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
R the windshield is dirty, fogged up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R there are no, several or unclear lane
markings for a lane, e.g. in areas with road
construction work
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 strong shadows cast on the lane
A warning may be given if a front wheel
passes over a lane marking. It will warn you
by means of intermittent vibration in the
steering wheel for up to 1.5 seconds.
Switching on Lane Keeping Assist X
Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive (Y page 195).
Symbol : appears in the multifunction
display.
If you drive at speeds above 40 mph
(60 km/h
) and lane markings are detected,
symbol : is highlighted. Lane Keeping
Assist is ready for use.
When Standard is selected, no warning
vibration occurs if:
R you switch 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 is selected, no warning
vibration occurs if:
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, e.g.
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 lanes quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when
necessary and in good time if you cross the
lane marking, the system recognizes certain
conditions 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
freeway.
R the system recognizes solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.184
Driving systems
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Safety systems
Display messages Possible causes/consequences and
M Solutions!÷
Currently
Unavailable See
Operator's Manual ABS (Anti-lock Braking System), ESP
®
(Electronic Stability
Program), BAS (Brake Assist), the HOLD function and hill start
assist are temporarily unavailable.
COLLISION PREVENTION ASSIST may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes are:
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
affected. The braking distance in an emergency braking situation
can increase.
If ESP ®
is not
operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Carefully drive a short distance on a suitable stretch of road,
making slight steering movements at a speed above 12 mph
(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
Operator's Manual ABS, ESP
®
, BAS, the HOLD function and hill start assist are
unavailable due to a malfunction.
COLLISION PREVENTION ASSIST may also have failed.
In addition, the J, ÷, å and ! warning lamps 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 wheels could therefore lock if you
brake hard, for example. Display messages
201On-board computer and displays Z
ProCarManuals.com

Display messages Possible causes/consequences and
M SolutionsThe steerability and braking characteristics may be severely
affected. The braking distance in an emergency braking situation
can increase.
If ESP
®
is not
operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. ÷
Currently
Unavailable See
Operator's Manual ESP
®
, BAS, the HOLD function and hill start assist are temporarily
unavailable.
COLLISION PREVENTION ASSIST may also have failed.
In addition, the ÷

and å warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
The self-diagnosis function might not be complete, for example.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not

operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Carefully drive a short distance on a suitable stretch of road,
making slight steering movements at a speed above 12 mph
(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.202
Display messages
On-board computer and displays
ProCarManuals.com

Display messages Possible causes/consequences and
M Solutions÷
Inoperative See
Operator's Manual ESP
®
, BAS, the HOLD function and hill start assist are unavailable
due to a malfunction.
COLLISION PREVENTION ASSIST may also have failed.
In addition, the ÷
and å warning lamps 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 in an emergency braking situation can thus
increase.
If ESP ®
is not

operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Drive on carefully.
X Visit a qualified specialist workshop. T!
÷
Inoperative See
Operator's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS, the
HOLD function and hill start assist are not available due to a
malfunction.
COLLISION PREVENTION ASSIST may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster and a warning tone sounds.
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 if you brake hard, for example.
The steerability and braking characteristics may be severely
affected. The braking distance in an emergency braking situation
can increase.
If ESP ®
is not

operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. F(USA
only)!(Canada
only) The red
F (USA only)/! (Canada only) indicator lamp
flashes and a warning tone sounds. A condition for automatic
release of the electric parking brake is not fulfilled ( Y page 150).
You are driving with the electric parking brake applied.
X Release the electric parking brake manually. Display messages
203
On-board computer and displays Z
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Display messages Possible causes/consequences and
M SolutionsPlease Release
Parking Brake
The red
F (USA only)/! (Canada only) indicator lamp
flashes and a warning tone sounds.
You are using the electric parking brake for emergency braking
(Y page 150). F(USA
only)!(Canada
only)
Parking Brake See
Operator's Manual The yellow
! warning lamp lights up.
The electric parking brake is malfunctioning.
To apply:
X Switch the ignition off.
X Press the electric parking brake handle for at least ten seconds.
X Shift the transmission to P.
X Consult a qualified specialist workshop. The yellow
! warning lamp and the red F (USA
only)/! (Canada only) indicator lamp light up.
The electric parking brake is malfunctioning.
To release:
X Switch off the ignition and turn it back on.
X Release the electric parking brake manually.
or
X Release the electric parking brake automatically ( Y page 150).
If the electric parking brake still cannot be released:
X Do not drive on.
X Consult a qualified specialist workshop.204
Display messagesOn-board computer and displays
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