2012 MERCEDES-BENZ B-CLASS ECO mode

?
To activate/deactivate air-recirculation mode ( Y page 129)
A To set the airflow ( Y page 126)
B To switch cooling with air dehumidification on/off ( Y page 123)
C To switch the rear window defroster on/off (Y page 128) Notes on using automatic climate
control
Automatic climate control The following contains notes and
recommendations on optimum use of the
automatic climate control.
R
Switch on the air-conditioning system by
turning control knob A clockwise to the
desired position (except position 0).
R Set the temperature to 72 ‡ (22 †).
R Recommendation for preventing
fogged up windows with low outside
temperatures
or rain: switch ¯ on for
the air distribution and switch P and
O off if possible (Y page 126).
In air-recirculation mode, switch d off
(Y page 129).
Set airflow control A to a setting between
3 and 6(Y page 126).
R Recommendation for rapid cooling or
heating of the vehicle interior: briefly set
airflow control A to a setting between 3
and 6(Y page 126).
R Recommendation for a constant
vehicle interior temperature: set airflow
control A to a setting between 1 and
3(Y page 126).
R Recommendation for air distribution in
the winter: set O and
¯(Y page 126).
Recommendation for air distribution in
the summer: set P or P and
¯(Y page 126).
R Only use the "windshield defrosting"
function briefly until the windshield is clear
again. R
Only use
air-recirculation

mode briefly, e.g.
if there are unpleasant outside odors or
when in a tunnel. The windows could
otherwise fog up, since no fresh air is drawn
into the vehicle in air-recirculation mode.
R If you change the settings of the climate
control system, the climate status display
appears for three seconds at the bottom of
the screen in the COMAND display. See
also the separate COMAND operating
instructions 4
. You will see the current
settings of the various climate control
functions.
ECO start/stop function During automatic engine switch-off, the ECO
start/stop function only operates at a
reduced capacity. If you require the full
climate control
output,

you can switch off the
ECO start/stop function by pressing the ECO
button ( Y page 138).
4 Only for vehicles with "COMAND Multimedia System" optional equipment120
Overview of climate control systemsClimate control
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Canada only
:
To set the temperature, left (Y page 125)
; To set climate control to automatic ( Y page 125)
= To defrost the windshield (Y page 127)
? To increase the airflow ( Y page 126)
A To set the air distribution ( Y page 126)
B Display
C To activate/deactivate air-recirculation mode ( Y page 129)
D To switch climate control on/off (Y page 123)
E To set the temperature, right (Y page 125)
F To switch the residual heat function on/off (Y page 129)
G To switch cooling with air dehumidification on/off ( Y page 123)
H To reduce the airflow ( Y page 126)
I To switch the rear window defroster on/off (Y page 128)
J To switch the ZONE function on/off (Y page 126) Notes on using dual-zone automatic
climate control
Automatic climate control The following contains instructions and
recommendations to enable you to get the
most out of your automatic climate control.
R
Activate climate control
using the à and
¿ buttons. The indicator lamps in the
à and ¿ buttons light up.
R Set the temperature to 72 ‡ (22 †). R
Only use the "windshield defrosting"
function briefly
until

the windshield is clear
again.
R Only use air-recirculation mode briefly, e.g.
if there are unpleasant outside odors or
when in a tunnel. The windows could
otherwise fog up, since no fresh air is drawn
into the vehicle in air-recirculation mode.
R Use the ZONE function to adopt the
temperature settings on the driver's side122
Overview of climate control systems
Climate control
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for the front-passenger side as well. The
indicator lamp
in
the á button goes out.
R Use the residual heat function if you want
to heat or ventilate the vehicle interior
when the ignition is switched off. The
residual heat function can only be activated
or deactivated with the ignition switched
off.
ECO start/stop function During automatic engine switch-off, the ECO
start/stop function only operates at a
reduced capacity. If you require the full
climate control
output,

you can switch off the
ECO start/stop function by pressing the ECO
button ( Y page 138). Operating the climate control
systems
Switching climate control on/off
Points to observe before use When the climate control is switched off, the
air supply and air circulation are also
switched off. The windows could fog up.
Therefore, switch off climate control only
briefly
Activating/deactivating
Automatic climate control
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To switch on: turn control A
clockwise to
the desired position (except position 0)
(Y page 119).
X To switch off: turn control A counter-
clockwise to position 0(Y page 119). Dual-zone automatic climate control
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To activate: press the à button.
The indicator
lamp

in the à button lights
up. Airflow and air distribution are set to
automatic mode.
or
X Press the ^ button.
The indicator lamp

in the ^ button goes
out. The previously selected settings are
restored.
X To deactivate: press the ^ button.
The indicator lamp

in the ^ button lights
up.
i Dual-zone automatic climate control:
switch on climate control primarily using
the à button. Activating/deactivating cooling with
air dehumidification
Points to observe before use If you deactivate the "Cooling with air-
dehumidification" function, the air inside the
vehicle will not be cooled. The air inside the
vehicle will also not be dehumidified. The
windows can
fog

up more quickly. Therefore,
only deactivate the "Cooling with air-
dehumidification" function briefly.
The cooling with air dehumidification function
is only available when the engine is running.
The air inside the vehicle is cooled and
dehumidified according to the temperature
selected.
Condensation may drip from the underside of
the vehicle when it is in cooling mode. This is
normal and not a sign that there is a
malfunction. Operating the climate control systems
123
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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Parking the vehicle for a long period
If you leave
the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked for longer than
six weeks, the vehicle may suffer damage as
a result of lack of use.
X Visit a qualified specialist workshop and
seek advice.
i You can obtain information about trickle
chargers from a qualified specialist
workshop. Driving tips
General notes
Important safety notes G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or

not at all. This could affect,
for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving. G
WARNING
If you operate mobile communication
equipment 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 this equipment when the vehicle
is stationary.
Observe the legal requirements for the
country in which you are driving. Some
jurisdictions prohibit the driver from using a
mobile phone while driving a vehicle.
If you make a call while driving, always use
hands-free mode. Only operate the telephone
when the traffic situation permits. If you are unsure, pull over to a safe location and stop
before operating the telephone.
Bear in mind that at a speed of only 30 mph
(approximately
50 km/h), the vehicle covers
a distance of 44 feet (approximately

14 m)
per second.
Drive sensibly – save fuel Observe the following tips to save fuel:
R
The tires should always be inflated to the
recommended tire pressure.
R Remove unnecessary loads.
R Remove roof racks when they are not
needed.
R Warm up the

engine at low engine speeds.
R Avoid frequent acceleration or braking.
R Have all maintenance work carried out as
indicated by the service intervals in the
Maintenance Booklet or by the service
interval display.
Fuel consumption also increases when
driving in cold weather, in stop-start traffic
and in hilly terrain.
Drinking and driving G
WARNING
Drinking and driving and/or taking drugs and
driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and
judgment.
The possibility of a serious or even fatal
accident are greatly

increased when you drink
or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs.
Emission control G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases

leads to poisoning. There152
Driving tips
Driving and parking
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is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces
without sufficient ventilation.
Certain engine systems
are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work at peak efficiency if
they are serviced exactly in accordance with
the manufacturer's specifications. For this
reason, only have work on the engine carried
out by qualified and authorized Mercedes-
Benz technicians.
The engine settings must not be changed
under any circumstances. Furthermore, all
specific service work must be carried out at
regular intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Maintenance Booklet. ECO display
The ECO display

gives you information on how
economical your driving style is. The ECO
display assists you in achieving the optimum
driving style in terms of consumption, taking
the actual and selected conditions into
consideration. Your driving style can
significantly influence the vehicle's
consumption. Example: ECO display
The ECO display consists of three bars:
R
Acceleration
R Constant
R Coasting
The percent value

is the average value of the
three bars. The three bars and the mean value
begin at the value of 50%. A higher percentage indicates a more economical
driving style.
The ECO display

does not indicate the actual
fuel consumption and a fixed percentage
count in the ECO display does not indicate a
fixed consumption figure.
Apart from driving style, consumption is
dependent on many factors such as, e.g.:
R Load
R Tire pressure
R Cold start
R Choice of route
R Electrical consumers switched on
These factors are not taken into
consideration by the ECO display.
The evaluation of your driving style is carried
out using the following three categories:
R Acceleration (evaluation of all
acceleration processes)
-The bar fills up: moderate acceleration,
especially at higher speeds
- The bar empties: sporty acceleration
R Constant (assessment of driving behavior
at all times)
-The bar fills up: constant speed and
avoidance of unnecessary acceleration
and deceleration
- The bar empties: fluctuations in speed
R Coasting (assessment of all deceleration
processes)
-The bar fills up: anticipatory driving,
keeping your distance and early release
of the accelerator. The vehicle can coast
without use of the brakes.
- The bar empties: frequent braking
i An economical driving style specially
requires driving at moderate engine
speeds.
To achieve a higher value in the categories
Acceleration and Constant:
R observe the gearshift recommendations.
R drive in drive program E. Driving tips
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brake pads. This can result in a significantly
longer braking distance.
R
Brake occasionally to
remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes !
If the red

brake warning lamp lights up in
the instrument cluster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
Observe additional warning messages in
the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at a qualified specialist workshop.
! A function or performance test should
only be carried out on a 2-axle
dynamometer. If you are planning to have
the vehicle tested on such a dynamometer,
contact an authorized Mercedes-Benz
Center to obtain further information first.
Otherwise, you could damage the drive
train or the brake system.
! As the ESP ®
system operates
automatically, the engine and the ignition
must be switched off (the SmartKey must
be in position 0 or 1 in the ignition lock) if:
R the electric parking brake is tested on a
brake dynamometer (for a maximum of
ten seconds)
R the vehicle is towed with the front axle
raised.
Braking triggered automatically by ESP ®
may seriously damage the brake system.
All checks and maintenance work on the
brake system must be carried out at a qualified specialist workshop. Consult a
qualified
specialist workshop

to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the
functionality of your brakes at regular
intervals.
You can find a description of Brake Assist
(BAS) on ( Y page 59).
Mercedes-Benz recommends that you only
have brake pads/linings installed on your
vehicle which have been approved for
Mercedes-Benz vehicles or which correspond
to an equivalent quality standard. Brake
pads/linings which have not been approved
for Mercedes-Benz vehicles or which are not
of an equivalent quality could affect your
vehicle's operating safety.
Mercedes-Benz recommends that you only
use brake fluid that has been specially
approved for your vehicle by Mercedes-Benz,
or which corresponds to an equivalent quality
standard. Brake fluid which has not been
approved for Mercedes-Benz vehicles or
which is not of an equivalent quality could
affect your vehicle's operating safety.
Checking brake lining thickness You can measure the break pad/lining
thickness using a test gauge. Color-coding
(green or
red)

on the test gauge allows you to
determine whether the brake pad/lining
thickness is still sufficient. The test gauge is
in the vehicle document wallet in the glove
box. Driving tips
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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
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