2012 MERCEDES-BENZ B-CLASS AUX

X
Turn the SmartKey to position 0 in the
ignition lock or remove it ( Y page 135).
X To activate: press the Ì button.
The indicator lamp
in the Ì button lights
up.
X To deactivate: press the Ì button.
The indicator lamp

in the Ì button goes
out.
i Residual heat is deactivated
automatically:
R after approximately 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R when the auxiliary heating is activated Setting the air vents
Important safety notes
G
WARNING
Very hot or very cold air can flow from the air
vents. This could

result in burns or frostbite in
the immediate vicinity of the air vents. There
is a risk of injury.
Make sure that all vehicle occupants always
maintain a sufficient distance to the air
outlets. If necessary, redirect the airflow to
another area of the vehicle interior.
In order to ensure the direct flow of fresh air
through the air vents into the vehicle interior,
please observe the following notes:
R keep the air inlet between the windshield
and the hood free of blockages, such as ice,
snow or leaves.
R never cover the air vents or air intake grilles
in the vehicle interior.
i You can move the adjusters for the air
vents vertically or horizontally to set the
direction of the airflow.
i For optimal climate control in the vehicle,
open the air vents completely and set the
adjusters to the central position. Setting the center air vents
X
To open the center air vent: turn the
adjuster in one of center air vents :
counter-clockwise.
X To close the center air vent: turn the
adjuster in one of center air vents :
clockwise until it engages. Setting the side air vents
:
Side window defroster vent
; Side air vent
X To open a side air vent: turn the adjuster
in side air vent ; counter-clockwise.
X To close a side air vent: turn the
adjuster
in side air vent ; clockwise until it
engages. 130
Setting the air vents
Climate control
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Problems with the transmission
Problem Possible causes/consequences and
M SolutionsThe transmission has
problems shifting gear. The transmission is losing oil.
X
Have the transmission checked at a qualified specialist
workshop immediately. The acceleration ability
is deteriorating.
The transmission no
longer shifts into all of
the gears.
Reverse gear can no
longer be engaged. The transmission is in emergency mode.
X
Stop the vehicle.
X Shift the transmission to position P.
X Switch off the engine.
X Wait at least 10 seconds before restarting the engine.
X Shift the transmission to position D.
X Have the transmission checked at a qualified specialist
workshop immediately. Refueling
Important safety notes
G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable,
the auxiliary heating before
refueling. G
WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make

sure that fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
R Wash away fuel from skin immediately
using soap and water.
R If fuel comes into contact with your eyes,
immediately rinse them thoroughly with clean water. Seek medical assistance
without delay.
R If fuel is swallowed, seek medical
assistance without delay. Do not induce
vomiting.
R Immediately change out of clothing which
has come into contact with fuel. G
WARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the

vehicle body before opening
the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged.
! Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the
ignition if you accidentally refuel with the
wrong fuel. Otherwise, the fuel will enter
the fuel system. Even small amounts of the
wrong fuel could result in damage to the
fuel system and the engine. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely. Refueling
147
Driving and parking Z
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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
157
Driving and parking Z
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If you press and hold
9 or :, the
rapid scrolling speed is increased. Not all
audio drives or data carriers support this
function.
If track information is stored on the audio
device or medium, the multifunction display
will show the number and title of the track.
The current track does not appear in audio
AUX mode (Auxiliary audio mode: external
audio source connected).
Video DVD operation DVD changer display (example)
:
Current DVD in the DVD changer
; Current scene
X Switch on COMAND and select video DVD;
see the separate operating instructions.
X Press the = or ; button on the
steering wheel to select the Audio menu.
X To select the next/previous scene:
briefly press the 9 or : button.
X To select a scene from the scene list
(rapid scrolling): press and hold the
9 or : button until desired
scene ; has been reached. Telephone menu
Introduction 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.
When telephoning, you must observe the
legal requirements for the country in which
you are currently driving.
X Switch on your mobile phone and audio
system or COMAND, see the separate
operating instructions.
X Establish a Bluetooth ®
connection to the
audio system or COMAND; see the
separate operating instructions.
X Press the = or ; button on the
steering wheel to select the Tel menu.
You will see one of the following display
messages in the multifunction display:
R Phone READY or the name of the network
provider: the mobile phone has found a
network and is ready to receive.
R Phone No Service: there is no network
available or the mobile phone is searching
for a network.
Accepting a call Example: incoming call
X
Press the 6 button on the steering
wheel to accept an incoming call.
If someone calls you when you are in the
Tel menu, a display message appears in the
multifunction display.
If you are not in the Tel menu, you can still
accept a call. Menus and submenus
193
On-board computer and displays Z
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Vehicle
Display messages Possible causes/consequences and
M SolutionsShift to 'P' or 'N'
to Start Engine You have attempted to start the engine with the transmission in
position R or D.
X
Shift the transmission to position P or N.Auxiliary Battery
Malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X
Visit a qualified specialist workshop at the next opportunity.
X Until then, set the automatic transmission to position P before
you switch off the engine.
X Before leaving the vehicle, apply the electric parking brake. Depress Brake to
Start Engine You have attempted to start the engine with the transmission in
position N without depressing the brake pedal.
X
Depress the brake pedal. To Deselect P or N,
Depress Brake and
Start Engine You have attempted to shift the transmission to position
R or D
without starting the engine.
X Start the engine.
X Depress the brake pedal.
i It is only possible to shift the transmission from position P to
the desired position if you depress the brake pedal. Only then
can the parking lock be deactivated. If you do not depress the
brake pedal, you can move the DIRECT SELECT lever but the
parking lock remains engaged.
i At transmission fluid temperatures below Ò4 ‡ (Ò20 †) you
can only shift out of position P into another transmission
position when the engine is running. Apply Brake to
Shift from 'P' You have attempted to move the transmission selector lever to
position R, N or D without depressing the brake pedal.
X
Depress the brake pedal. Transmission Not
in P
Risk of Vehicle
Rolling Away The driver's door is open and the transmission is in position
R, N
or D.
A warning tone also sounds.
X Shift the transmission to position P.
X Secure the vehicle against rolling away ( Y page 149).220
Display messagesOn-board computer and displays
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Stowage compartment in front of the
armrest (vehicles with automatic
transmission)
X
To open: press the marking on cover :.
i You can remove
the non-slip mat and the
insert for cleaning. When removing the
insert you will have to overcome some
slight resistance.
Stowage compartment under the armrest X
To open: on vehicles with moveable
armrests, make sure that the armrest is in
the rearmost position.
X Press button : and fold the armrest up.
i Depending on the vehicle's equipment, a
USB connection and

an AUX IN connection
or a Media Interface are installed in the
stowage compartment. A Media Interface
is a universal interface for mobile audio
equipment, e.g. for an iPod ®
or MP3 player
(see the separate COMAND Operating
Instructions). Stowage compartment under the driver's
seat and front-passenger seat G
WARNING
If you exceed the maximum load for the
stowage compartment, the cover may not be
able to restrain the items. Items may be
thrown out of the stowage compartment and
hit vehicle occupants.

There is a risk of injury,
particularly in the event of sudden braking or
a sudden change in direction.
Never exceed the maximum permissible load
for the stowage compartment. Stow and
secure heavy objects in the cargo
compartment.
The maximum permissible load of the
stowage compartment is 2.6 lbs (1.5 kg). X
To open: pull handle : up and fold
cover ; forwards.
Stowage space in the rear Stowage compartment in the rear center
console238
Stowage areas
Stowage and features
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Fuel
Important safety notes G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable,
the auxiliary heating before
refueling. G
WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make

sure that fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
R Wash away fuel from skin immediately
using soap and water.
R If fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance
without delay.
R If fuel is swallowed, seek medical
assistance without delay. Do not induce
vomiting.
R Immediately change out of clothing which
has come into contact with fuel.
Tank capacity Model Total
capacity B 250 BlueEFFICIENCY
13.2 US gal
(50.0 l) Model Of which
reserve B 250 BlueEFFICIENCY
Approx.
1.6 US gal (6.0 l) Gasoline
Fuel grade
!
Do not use

diesel to refuel vehicles with a
gasoline engine. Do not switch on the
ignition if you accidentally refuel with the
wrong fuel. Otherwise, the fuel will enter
the fuel system. Even small amounts of the
wrong fuel could result in damage to the
fuel system and the engine. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely.
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline may be used.
If there is no premium-grade unleaded
gasoline available and regular unleaded
gasoline must be used, please observe the
following precautions:
R only fill the fuel tank to half full with
regular unleaded gasoline and fill the rest
with premium-grade unleaded gasoline
as soon as possible.
R do not drive at the maximum speed.
R avoid sudden acceleration.330
Service products and filling capacities
Technical data
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