warning MERCEDES-BENZ B-CLASS 2012 Owners Manual

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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The Park Assist Active Select R
Observe Surroundings

message appears in
the multifunction display.
X Further transmission shifts may be
necessary.
As soon as the parking procedure is
complete, the Park Assist Finished
message appears in the multifunction
display.
Active Parking Assist is then deactivated.
PARKTRONIC is still available.
X Maneuver if necessary.
X Always observe the warning messages
displayed by PARKTRONIC (
Y page 170).
Parking tips:
R The way your vehicle is positioned in the
parking space after parking is dependent
on various factors. These include the
position and shape of the vehicles parked
in

front and
behind it and the conditions of
the 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 curb. If necessary, you should
cancel the parking procedure with Active
Parking Assist.
R You can also engage forward gear
prematurely. The vehicle redirects and
does not drive as far into the parking space.
Should a gear be changed too early, the
parking procedure will be canceled. A
sensible parking position can no longer be
achieved from this position.
Exiting a parking space In order that Active Parking Assist can
support you
when

you exit the parking space:
R the border of the parking space must not
be too low.
R the border of the parking space must not
be too wide. The system maneuvers the
vehicle into a position at a maximum of 45° to the starting position in the parking
space.
R a maneuvering distance of at least 24 in
(0.60 m) must be available.
Active Parking Assist

can only assist you with
exiting a parking space if you have parked the
vehicle using Active Parking Assist.
X Start the engine.
X Switch on the turn signal on the side facing
the street.
X Shift the transmission to position D or 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 exit a parking space 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 Reverse the vehicle or drive forwards, being
ready to brake at all times. Do not exceed
a maximum speed of approximately
6 mph (10 km/h) when exiting a parking
space. Otherwise

Active Parking Assist will
be canceled.
X Stop when PARKTRONIC sounds the
continuous warning tone, if not before.
X Shift the transmission to position D or R
as
required 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. 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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Lanes
:
White guide line without turning the
steering wheel, vehicle width including
the exterior mirrors (static)
; Yellow lane marking tires at current
steering wheel angle,
vehicle width to the
outer side of the wheels (dynamic)
= Red guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic)
? Bumper Guide lines
?
Bumper
A Red guide line at a distance of
approximately 10 in (0.25 m
) from the
rear of the vehicle
B Yellow guide line at a distance of
approximately

13 ft (
4.0 m) from the rear
of the vehicle
C Vehicle center axle (marker assistance)
D Yellow guide line at a distance of
approximately 3 ft (1.0 m ) from the rear
of the vehicle The lanes and guide lines are only displayed
if you have engaged reverse gear.
The distance specifications only apply to
objects that are at ground level.
Additional displays on vehicles with PARKTRONIC
and COMAND
:
Front warning display
; Additional PARKTRONIC measurement
operational readiness indicator
= Rear warning display
Vehicles with PARKTRONIC and
COMAND: if PARKTRONIC is operational
(Y page 169), an additional operational
readiness indicator will appear in COMAND
display ;.If the PARKTRONIC warning
displays are active or light up, warning
displays : and
=


are also active or light up
correspondingly in the COMAND display.
Reverse parking function X
Make sure that the rear view camera is
activated and the "Reverse parking"
function is selected; see the separate
operating instructions for the audio
system/COMAND.
The lane and the guide lines are shown.178
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Driving to the final position
:
White lane at current steering wheel angle
; Parking space marking
X Turn the steering wheel to the center
position while the vehicle is stationary. :
Red guide line at a distance of
approximately 10 in (0.25 m
) from the
rear of the vehicle
; White lane with steering wheel straight
= End of parking space
X Back up carefully until you have reached
the final position.
Red guide line :
is
then

at end of parking
space =. The vehicle is almost parallel in
the parking space. ATTENTION ASSIST
General notes ATTENTION ASSIST helps you during long,
monotonous journeys, such as on highways.
It is active in the range between 50 mph
(80 km/h) and 112 mph (180 km/h). If ATTENTION ASSIST detects typical
indicators of fatigue or increasing lapses in
concentration on the part of the driver, it
suggests you take a break.
Important safety notes
ATTENTION ASSIST is only an aid to the
driver. It might not always recognize fatigue
or increasing
inattentiveness

in time or fail to
recognize them at all. The system is not a
substitute for a well-rested and attentive
driver.
ATTENTION ASSIST assesses your level of
fatigue or lapses in concentration by taking
the following criteria into account:
R your personal driving style, e.g. steering
characteristics
R journey details, e.g. time of day and length
of journey
The functionality of ATTENTION ASSIST is
restricted and warnings may be delayed or
not occur at all:
R if the road condition is poor, e.g. if the
surface is uneven or if there are potholes
R if there is a strong side wind
R if you have adopted a sporty driving style
with high cornering speeds or high rates of
acceleration
R if you are predominantly driving slower
than 50 mph (80 km/h) or faster than
112 mph (180 km/h)
R if you are currently using COMAND or
making a telephone call with it
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed180
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Warning and display messages in the
multifunction display
X
Activate ATTENTION ASSIST using the on-
board computer ( Y page 195).
Symbol : appears in the multifunction
display.
If ATTENTION ASSIST is active, it will not
warn you until at least 20 minutes after
your journey has begun. You then hear an
intermittent warning tone twice and the
Attention Assist: Drowsiness
Detected message appears in the
multifunction display.
X If necessary, take a break.
X Press the
a button to confirm the
message.
On long journeys, take regular breaks in good
time to allow yourself to rest properly. If you
do not take

a break, you will be warned again
after 15 minutes at the earliest. The
precondition for this is that
ATTENTION ASSIST still detects typical
indicators of fatigue or increasing lapses in
concentration.
ATTENTION ASSIST is reset when you
continue your journey and starts assessing
your tiredness again if:
R you switch off the engine.
R you take off your seat belt and open the
driver's door, e.g. for a change of drivers or
to take a break. Lane Tracking package
General notes The Lane Tracking package consists of Blind
Spot Assist (
Y

page 181) and Lane Keeping
Assist (Y page 183).
Blind Spot Assist Important safety notes
G
WARNING
Blind Spot Assist does not react to:
R vehicles overtaken too closely on the side,
placing them in the blind spot area
R vehicles approaching and driving by with a
speed difference of more than 6.8 mph
(11 km/h )
As a result, Blind Spot Assist may not give
warnings in

such situations. There is a risk of
an accident.
Always observe the traffic conditions
carefully, and maintain a safe lateral distance.
Blind Spot Assist is only an aid. It may fail to
detect some vehicles and is no substitute for
attentive driving.
i USA only:
This device has been approved by the FCC
as a "Vehicular Radar System". The radar
sensor is intended for use in an automotive
radar system only. Removing, tampering
with, or altering the device will void any
warranties, and is not permitted by the
FCC. 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.
General notes
Blind Spot Assist uses a radar sensor system
to monitor the areas on both sides of your
vehicle. It supports you from a speed of
approximately 20 mph (30 km/h). A warning
display in the exterior mirrors draws your
attention to vehicles detected in the Driving systems
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monitored area. If you then switch on the
corresponding turn signal to change lanes,
you will also receive a visual and audible
collision warning.
For
this purpose, Blind Spot
Assist uses sensors in the rear bumper.
For Blind Spot Assist to assist you when
driving, the radar sensor system must be:
R activated(Y page 199)
R operational
Monitoring range of the sensors
In particular, the detection of obstacles can
be impaired if:
R dirt on the sensors or anything else
covering the sensors
R there is poor visibility, e.g. due to fog, heavy
rain or snow
R a narrow vehicle traveling in front, e.g. a
motorbike or bicycle
R the road has very wide lanes
R the road has narrow lanes
R you are not driving in the middle of the lane
R there are barriers or similar lane borders
Vehicles in the monitoring range are then not
indicated. Blind Spot Assist monitors the area up to
10 ft (
3.0 m

) behind your vehicle and directly
next to your vehicle, as shown in the diagram. For this purpose, Blind Spot Assist uses radar
sensors in the rear bumper.
If the
lanes

are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may
be indicated, especially if the vehicles are not
driving in the middle of their lane. This may
be the case if the vehicles are driving on the
inner side of their lane.
Due to the nature of the system:
R warnings may be issued in error when
driving close to crash barriers or similar
solid lane borders.
R warnings may be interrupted when driving
alongside particularly long vehicles, e.g.
trucks, for a prolonged time.
The two sensors for Blind Spot Assist are
integrated into the sides of the rear bumper.
Make sure that the bumper is free of dirt, ice
or slush in the vicinity of the sensors. For
example, the radar sensors must not be
covered by bicycle racks or overhanging
loads. Following a severe impact or in the
event of damage to the bumpers, have the
function of the radar sensors checked at a
qualified specialist workshop. Blind Spot
Assist may otherwise not work properly.
Indicator and warning display
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated. :
Yellow indicator lamp/red warning lamp
When Blind Spot Assist is activated, indicator
lamp : in the exterior mirrors lights up
yellow at speeds

of up to 20 mph (30 km/h).182
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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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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
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