2012 MERCEDES-BENZ B-CLASS change time

Winter driving
General notes G
WARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine
braking on a slippery road surface. G
DANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases
such as carbon
monoxide (CO) may enter the
vehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open
a window on the side of the vehicle that is not
facing into the wind.
Have your vehicle winterproofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Winter operation"
section ( Y page 300).
Driving with summer tires Observe the notes in the "Winter operation"
section (
Y page 300).
Slippery road surfaces G
WARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine
braking on a slippery road surface. If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X
Shift the transmission to position N.
Drive particularly carefully on slippery road
surfaces. Avoid sudden

acceleration, steering
and braking maneuvers. Do not use the cruise
control or DISTRONIC PLUS.
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Changes in the outside temperature are
displayed after a short delay.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges. You
should pay special attention to road
conditions when temperatures are around
freezing point.
i For more information on driving with
snow chains, see ( Y page 301). Driving systems
Cruise control
Important safety notes If you fail to adapt your driving style, cruise
control can neither reduce the risk of an
accident nor override the laws of physics.
Cruise control cannot take into account the
road, traffic and weather conditions. Cruise
control is only

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.
Do not use cruise control:
R in road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
R on slippery road surfaces. Braking or
accelerating could cause the drive wheels Driving systems
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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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In such cases, DISTRONIC PLUS may:
R
give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
R accelerate unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, in particular when warned to do so by
DISTRONIC PLUS. G
WARNING
DISTRONIC PLUS brakes your vehicle with up
to 40% of the maximum braking force. If this
braking force is
insufficient, DISTRONIC PLUS
warns you visually and audibly. There is a risk
of an accident.
In such cases, apply the brakes yourself and
try to take evasive action.
! 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
If you fail to adapt your driving style,
DISTRONIC PLUS can neither reduce the risk
of accident nor override the laws of physics.
DISTRONIC PLUS cannot take into account
the road, traffic and weather conditions.
DISTRONIC PLUS is only 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.
Do not use DISTRONIC PLUS:
R in road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
R on slippery road surfaces. Braking or
accelerating could cause the drive wheels to lose traction and the vehicle could then
skid
R when there is

poor visibility, e.g. due to fog,
heavy rain or snow
DISTRONIC PLUS may not detect narrow
vehicles driving in front, e.g. motorcycles, or
vehicles driving on a different line.
In particular, the detection of obstacles can
be impaired if:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other radar sources
R strong radar reflections, for example, in
parking garages
If DISTRONIC PLUS no longer detects a
vehicle in front, DISTRONIC PLUS may
unexpectedly accelerate the vehicle to the
stored speed.
This speed may:
R be too high if you are driving in a filter lane
or an exit lane
R be so high when driving in the right-hand
lane that you overtake vehicles in the left-
hand lane
R be so high when driving in the left-hand lane
that you overtake vehicles in the right-hand
lane
If there is a change of drivers, advise the new
driver of the speed stored.
General notes DISTRONIC PLUS regulates the speed and
automatically helps you maintain the
distance to the vehicle detected in front.
DISTRONIC PLUS brakes automatically so
that the set speed is not exceeded.
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 154).

By doing so, you will
make use of the braking effect of the engine.
This relieves the load on the brake system and 160
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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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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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