2012 MERCEDES-BENZ B-CLASS Owners Manual

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Assist is no longer active.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
183
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
Driving and parking
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Useful information ............................
186
Important safety notes ....................186
Displays and operation .................... 186
Menus and submenus ...................... 189
Display messages ............................. 200
Warning and indicator
lamps in the
instrument cluster ............................224 185
On-board computer and displays
ProCarManuals.com

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note
that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 24).Important safety notes
G
WARNING
If you operate information systems and
communication equipment integrated in the
vehicle while driving, you will be distracted
from traffic conditions. You could also lose
control of the vehicle. There is a risk of an
accident.
Only operate the equipment when the traffic
situation permits. If

you are not sure that this
is possible, park the vehicle paying attention
to traffic conditions and operate the
equipment when the vehicle is stationary. G
WARNING
If the instrument cluster has failed or
malfunctioned, you may not recognize
function restrictions in systems relevant to
safety. The operating safety of your vehicle
may be impaired. There is a risk of an
accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop
immediately.
You must observe the legal requirements for
the country in

which you are currently driving
when operating the on-board computer.
The on-board computer only shows messages
or warnings from certain systems in the multifunction display. You should therefore
make sure your vehicle is operating safely at
all times. Otherwise, a vehicle that is not
operating safely may cause an accident.
For an overview, see the instrument panel
illustration (
Y page 29). Displays and operation
Instrument cluster lighting
The lighting in the instrument cluster, in the
displays and the controls in the vehicle
interior can be

adjusted using the brightness
control knob.
The brightness control knob is located on the
bottom left of the instrument cluster
(Y page 29).
X Turn the brightness control knob clockwise
or counter-clockwise.
If the light switch is set to Ã, T or
L, the brightness is dependent upon
the brightness of the ambient light.
i The light sensor

in the instrument cluster
automatically controls the brightness of
the multifunction display.
In daylight, the displays in the instrument
cluster are not illuminated. Coolant temperature display
G
WARNING
Driving when your engine is overheated can
cause some fluids

which may have leaked into
the engine compartment to catch fire. You
could be seriously burned.
Steam from an overheated engine can cause
serious burns which can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Stop the vehicle in a safe location away from
other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until
the engine has cooled down. 186
Displays and operation
On-board computer and displays
ProCarManuals.com

!
A display message
is shown if the coolant
temperature is too high.
If the coolant temperature is over
248 ‡(120 †), do not continue driving. The
engine will otherwise be damaged.
The coolant temperature gage is in the
instrument cluster on the right-hand side.
Under normal operating conditions and with
the specified coolant level, the coolant
temperature may rise to 248 ‡ (120 †). Tachometer
! Do not drive in the overrevving range, as
this could damage the engine.
The red band

in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached. Outside temperature display
You should pay special attention to road
conditions when temperatures are around
freezing point.
The outside temperature display is in the
multifunction display.
Changes in the outside temperature are
displayed after a short delay. Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
R Cruise control activated ( Y page 157):
The segments light up from the stored
speed to the maximum speed.
R DISTRONIC PLUS activated (Y page 159):
One or two segments in the set speed
range light up.
R DISTRONIC PLUS detects

a vehicle in front:The segments between the speed of the
vehicle in front and the stored speed light
up. Operating the on-board computer
Overview :
Multifunction display
; Switches on the Voice Control System;
see the separate operating instructions
= Right control panel
? Left control panel
A Back button
X To activate the on-board computer: turn
the SmartKey to position 1 in the ignition
lock.
You

can control the multifunction display and
the settings in the on-board computer using
the buttons on the multifunction steering
wheel. Displays and operation
187
On-board computer and displays Z
ProCarManuals.com

Left control panel
=
; R
Calls up the
menu and menu bar9
:
Press briefly:
R
Scrolls in lists
R Selects a submenu or function
R In the Audio menu: selects a
stored station, an audio track or
a video scene
R In the Tel(telephone) menu:
switches to the phone book and
selects a name or telephone
number 9
:
Press and hold:
R
In the Audio menu: selects the
previous/next station or selects
an audio track or a video scene
using rapid scrolling
R In the Tel (Telephone) menu,
starts rapid
scrolling

through the
phone book a R
Confirms a selection/display
message
R In the Tel (telephone) menu:
switches to the telephone book
and starts dialing the selected
number
R In the Audio menu: stops the
station search function at the
desired station Right control panel
~ R
Rejects or ends a call
R Exits phone book/redial
memory 6 R
Makes or accepts a call
R Switches to the redial memory W
X R
Adjusts the volume 8 R
Mute Back button
%
Press briefly:
R
Back
R Switches off the Voice Control
System; see the separate
operating instructions
R Hides display messages/calls
up the last Trip menu function
used
R Exits the telephone book/redial
memory %
Press and hold:
R
Calls up the standard display in
the Trip menu Multifunction display
:
Time
; Permanent display: outside temperature
or speed ( Y page 197)
= Text field
? Menu bar188
Displays and operationOn-board computer and displays
ProCarManuals.com

A
Drive program (Y page 141)
B Transmission position ( Y page 141)
X To show menu bar ?: press the =
or ; button on the steering wheel.
Menu bar ? disappears after a few seconds.
Text field = shows the selected menu or
submenu as well as display messages.
i You can set the time using the audio
system or COMAND; see the separate
operating instructions.
The following messages may appear in the
multifunction display:
XjY Active Parking Assist (Y page 172)
CRUISE Cruise Control (Y page 157)
è Rear window wiper ( Y page 112)
_ Adaptive Highbeam Assist
(Y page 102)
À ATTENTION ASSIST (Y page 180)
à Lane Keeping Assist (Y page 183)
ë HOLD function ( Y page 167)
Ä Distance warning function
(Y page 233) Menus and submenus
Menu overview
Operating the on-board computer
(Y page 187).
Depending on the equipment installed in the
vehicle, you can call up the following menus:
R Trip menu (Y page 189)
R Navi menu (navigation instructions)
(Y page 191)
R Audio menu (Y page 192)
R Tel (telephone) menu ( Y page 193)
R DriveAssist (Assistance) menu
(Y page 194)
R Serv menu (Y page 196)
R Sett menu (Y page 196) The
Audio, Navi and
Tel
menus differ slightly
in vehicles with Audio 20 and in vehicles with
COMAND. The examples given in this
Operator's Manual apply to vehicles
equipped with COMAND. Trip menu
Standard display X
Press and hold the % button on the
steering wheel until the Trip menu with
trip odometer : and odometer ; is
shown.
Trip computer "From Start" or "From
Reset" Example: trip computer "From Start"
:
Distance
; Time
= Average speed
? Average fuel consumption
X Press the = or ; button on the
steering wheel to select the Trip menu.
X Press the 9 or : button to select
From Start or From Reset.
The values in the From Start submenu are
calculated from the start of a journey, while
the values in the From Reset submenu are
calculated from the last time the submenu
was reset ( Y page 190). Menus and submenus
189
On-board computer and displays Z
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The From Start trip computer is
automatically reset when:
R
the ignition has
been switched off for more
than four hours.
R 999 hours have been exceeded.
R 9,999 miles have been exceeded.
If the value exceeds 9,999 hours or
99,999 miles, the From Reset trip computer
is automatically reset.
ECO display Example: ECO display
X
Press the = or ; button on the
steering wheel to select the Trip menu.
X Press 9 or : to select ECO
DISPLAY.
If the ignition remains switched off for longer
than four hours, the ECO display will be
automatically reset.
Further information on the ECO display
(Y page 153).
Displaying the range and current fuel
consumption X
Press the = or ; button on the
steering wheel to select the Trip menu.
X Press the 9 or : button to select
current fuel consumption ; and
approximate range :. Approximate range : is calculated
according to
the
current driving style and the
amount of fuel in the tank. If there is only a
small amount of fuel left in the fuel tank, the
display shows a vehicle being refueled C
instead of range :.
Digital speedometer X
Press the = or ; button on the
steering wheel to select the Trip menu.
X Press the 9 or : button to select
digital speedometer :.
Resetting values Example: resetting the trip computer "From Start"
You can reset the values of the following
functions:
R
Trip odometer
R "From Start" trip computer
R "From Reset" trip computer
R ECO display
X Press the = or ; button on the
steering wheel to select the Trip menu.
X Press the 9 or :
button to select the
function that you wish to reset.
X Press the a button.
X Press the : button to select Yes and
press a to confirm. 190
Menus and submenus
On-board computer and displays
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