air MERCEDES-BENZ C-Class 2011 W204 Service Manual

Control panel for the dual-zone automatic climate controlFunctioniNotes/tips:Sets the temperature, leftSet the temperature to 72 ‡ (22 †).;Sets climate control to
automaticActivate climate control using the à and ¿
buttons. The indicator lamps in the à and ¿
buttons light up.=Switches climate control on/
offActivate climate control using the à and ¿
buttons. The indicator lamps in the à and ¿
buttons light up.?Switches the MONO/ZONE
function on/off 13
Switches maximum cooling
MAX COOL on/off 14Use the MONO function if you want to adopt the
temperature and air distribution settings from the
driver's side for the front-passenger side. The
indicator lamp in the º button lights up.ASwitches cooling with air
dehumidification on/offActivate climate control using the à and ¿
buttons. The indicator lamps in the à and ¿
buttons light up.BDefrosts the windshieldOnly use the "defrosting" function briefly until the
windshield is clear again.CActivates/deactivates air-
recirculation modeOnly use "air-recirculation" mode briefly, e.g. if there
are unpleasant outside odors or when in a tunnel. The
windows could otherwise fog up as, in air-
recirculation mode, no fresh air is drawn into the
vehicle.DSets the temperature, rightSet the temperature to 72 ‡ (22 †).ESwitches the rear window
heating on/offFIncreases the airflow13 Only for Canada.
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FunctioniNotes/tipsGReduces the airflowHDisplayISets the air distributionOperating the control systems
Switching the control on/off
Important information
GWarning!
When the climate control system is
deactivated, the outside air supply and
circulation are also deactivated. Only choose
this setting for a short time. Otherwise the
windows could fog up, impairing visibility and
endangering you and others.
i Activate climate control primarily using
the à button ( Y page 123).
Activating/deactivating
XTurn the key to position 2 in the ignition
lock.XTo activate: press the à button.
The indicator lamp in the à button lights
up. Airflow and air distribution are set to
automatic mode.
or
XPress the ^ button.
The indicator lamp in the ^ button goes
out. The previously selected settings come
into effect again.XTo deactivate: press the ^ button.
The indicator lamp in the ^ button lights
up.Switching cooling with air
dehumidification on/off
Important information
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.
GWarning
If you switch off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
Condensation may drip from the underside of
the vehicle when automatic climate control is
in cooling mode. This is normal and not a sign
that there is a malfunction.
i The cooling with air dehumidification
function uses refrigerant R134a. This
coolant does not contain
chlorofluorocarbons, and therefore does
not damage the ozone layer.
Activating/deactivating
i The evaporator is ventilated when the air-
conditioning system is operated. The
blower switches on automatically
approximately one hour after the vehicle is
locked. The blower runs for 30 minutes on
the lowest level. The blower noise is normal
and not a sign that there is a malfunction.
If you unlock the vehicle during this time,
the ventilation will be interrupted. To save
battery power, the evaporator will not
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ventilate automatically if the starter battery
is weak.XTo switch on: press the ¿ button.
The indicator lamp in the ¿ button lights
up.XTo switch off: press the ¿ button.
The indicator lamp in the ¿ button goes
out. The cooling with air dehumidification
function has a delayed switch-off feature.
Problems with the "cooling with air
dehumidification" function
If the indicator lamp in the ¿ button does
not go out when switched off, the cooling with
air dehumidification function is switched off
due to a malfunction. You can no longer
activate the cooling with air dehumidification
function.
XConsult a qualified specialist workshop.
Setting climate control to automatic
GWarning
If you switch off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
In automatic mode, the set temperature is
maintained automatically at a constant level.
The system automatically regulates the
temperature of the dispensed air, the airflow
and the air distribution.
Automatic mode will achieve optimal
operation if cooling with air dehumidification
is also activated. If desired, cooling with air
dehumidification can be deactivated.
XTurn the SmartKey to position 2 in the
ignition lock.XSet the desired temperature.XTo activate: press the à button.
The indicator lamp in the à button lights
up. Automatic air distribution and airflow
are activated.XTo deactivate: press the _ button.
or
XPress the K or I button.
The indicator lamp in the à button goes
out. Automatic air distribution and airflow
are deactivated.
Setting the temperature
Different temperatures can be set for the
driver's and front-passenger sides.
XTurn the SmartKey to position 2 in the
ignition lock.XTo increase/reduce: turn controls : and
D clockwise or counter-clockwise
( Y page 121). Only change the temperature
setting in small increments. Start at
72 ‡ (22 †).
Setting the air distribution
Dual-zone automatic climate control: the air
distribution can be set individually for the
driver's and front-passenger sides.
¯directs the airflow through the
defroster ventsPdirects the airflow through the center
and side air ventsOdirects the airflow through the footwell
air ventsSdirects the airflow through the center
and side air vents, as well as the
footwell air vents 1515
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_directs the airflow to the entire vehicle
interior 16bdirects the airflow through the
defroster, center and side air vents 16adirects the airflow through the footwell
and defroster vents
i Regardless of the air distribution setting,
airflow is always directed through the side
air vents. The side air vents can only be
closed when the controls on the side air
vents are turned downwards.
XTurn the key to position 2 in the ignition
lock.XPress the _ button repeatedly until the
desired symbol appears in the display.
The indicator lamp in the à button goes
out. Automatic control is deactivated and
the air distribution is controlled according
to the selected setting.
Setting the airflow
XTurn the SmartKey to position 2 in the
ignition lock.XTo increase/reduce: press the K or
I button.
Switching the MONO function on/off
This function is only available in vehicles in
Canada.
You can use the MONO function to adopt the
temperature and air distribution settings on
the driver's side for the front-passenger side.
XPress the º button.
The indicator lamp in the º button lights
up or goes out.Defrosting the windshield
You can use this function to defrost the
windshield or to defrost the inside of the
windshield and the side windows.
i You should only select the defrosting
function until the windshield is clear again.XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the ¬ button.
The indicator lamp in the ¬ button lights
up.
The climate control system switches to the
following functions:
R cooling with air dehumidification on
R high airflow 17
R high temperature 17
R air distribution to the windshield and
front side windows
R air-recirculation mode offXTo deactivate: press the ¬ button.
The indicator lamp in the ¬ button goes
out. The previously selected settings come
into effect again. The cooling with air
dehumidification function remains on. Air-
recirculation mode remains deactivated.
or
XPress the à button.
The indicator lamp in the ¬ button goes
out. Airflow and air distribution are set to
automatic mode.
or
XTurn controls : or D clockwise or
counter-clockwise ( Y page 121).
or
XPress the K or I button.
Maximum cooling MAX COOL
The MAX COOL function is only available in
vehicles for the USA.
16 Canada only.
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MAX COOL is only operational when the
engine is running.
When you activate MAX COOL, climate
control switches to the following functions:
R maximum cooling
R maximum airflow
R air-recirculation mode onXTo activate: press the Ù button.
The indicator lamp in the button lights up.XTo deactivate: press the Ù button
again.
The indicator lamp goes out. The previously
selected settings come into effect again.
Defrosting the windows
Windows fogged up on the inside
XActivate the "cooling with air
dehumidification" function ¿.XActivate automatic mode Ã.XIf the windows continue to fog up, activate
the defrosting function ( Y page 124).
i
You should only select this setting until
the windshield is clear again.
Windows fogged up on the outside
XSwitch on the windshield wipers.XPress the _ button repeatedly until the
O or P symbol appears in the
display.
i You should only select this setting until
the windshield is clear again.
Rear window heating
Activating/deactivating
GWarning
Any accumulation of snow and ice should be
removed from the rear window before driving.
Visibility could otherwise be impaired,
endangering you and others.
The rear window heating has a high current
draw. You should therefore switch it off as
soon as the window is clear as it only switches
off automatically after several minutes.
If the battery voltage is too low, the rear
window heating may switch off.XTurn the SmartKey to position 2 in the
ignition lock.XPress the ¤ button.
The indicator lamp in the ¤ button lights
up or goes out.
Problems with the rear window heating
The rear window heating has deactivated
itself prematurely or cannot be activated.
XSwitch off any consumers that are not
required, e.g. reading lamps or interior
lighting.
When the battery is sufficiently charged,
the rear window heating is activated again
automatically.
Activating/deactivating air-
recirculation mode
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle
from outside. The air already inside the
vehicle will then be recirculated.
GWarning
Fogged windows impair visibility,
endangering you and others. If the windows
begin to fog on the inside, switching off the
air recirculation mode immediately should
clear interior window fogging. If interior
window fogging persists, make sure the air
conditioning is activated, or press the ¬
button.
XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the g button.
The indicator lamp in the g button lights
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iAir-recirculation mode is activated
automatically at high outside
temperatures. When air-recirculation mode
is activated automatically, the indicator
lamp in the g button is not lit.
Outside air is added after about 30
minutes.
XTo deactivate: press the g button.
The indicator lamp in the g button goes
out.
iAir-recirculation mode switches off
automatically:
Rafter approximately five minutes if
outside temperatures are under about
41 ‡ (5 †)
Rafter approximately five minutes if
cooling with air dehumidification is
deactivated
Rafter approximately 30 minutes if outside
temperatures are over about
41 ‡ (5 †)
Setting the air vents
Important safety notes
GWarning
When operating the climate control, the air
that enters the passenger compartment
through the air vents can be very hot or very
cold (depending on the set temperature). This
could cause burns or frostbite to unprotected
skin in the immediate area of the air vents.
Always keep sufficient distance between
unprotected parts of the body and the air
vents. If necessary, use the air distribution
adjustment to direct the air to air vents in the
vehicle interior that are not in the immediate
area of unprotected skin.
In order to ensure the direct flow of fresh air
through the air vents into the vehicle interior,
please observe the following notes:
Rkeep the air inlet between the windshield
and the hood free of blockages, such as ice,
snow or leaves
Rnever cover the vents or air inlet and outlet
grilles in the vehicle interior.
iFor virtually draft-free ventilation, adjust
the sliders of the air vents to the center
position.
Setting the center air vents
:Center air vent, left;Center air vent, right=Center vent thumbwheel, right?Center vent thumbwheel, leftXTo open/close: turn thumbwheels =
and ? up or down.
Setting the side air vents
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XTo open/close: turn thumbwheel = up or
down.
iSide window defroster vent : is never
completely shut, even if side air vent ; is
shut.
Setting the air vent in the glove box
When automatic climate control is activated,
the glove box can be ventilated, for instance
to cool its contents. The level of airflow
depends on the airflow and air distribution
settings.
! Close the air vent when heating the
vehicle.
At high outside temperatures, open the air
vent and activate the "cooling with air
dehumidification" function. Otherwise,
temperature-sensitive items stored in the
glove box could be damaged.
:Air vent thumbwheel;Air ventXTo open/close: turn thumbwheel :
clockwise or counter-clockwise.
Setting the rear-compartment air
vents
Setting the center vents in the rear
compartment
:Rear-compartment air vent thumbwheel;Rear-compartment air vent, right=Rear-compartment air vent, leftXTo open/close: turn thumbwheel : up or
down.
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Refueling
Important safety notes
GWarning
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flames or smoking
materials near gasoline.
Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and any skin or clothing
contact.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging to your
health.
GWarning
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gasoline
to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.
GWarning!
C 300 and C 300 Sport with automatic
transmission:
Flexible Fuel Vehicles (identified by a label
reading Premium gasoline or E85 only! on
the fuel filler flap):
Ethanol fuel (E85) and its fumes are highly
flammable, poisonous and burn easily.
Ethanol fuel can cause serious injuries if
ignited or if you come into contact with it or
inhale fumes of it. Avoid inhalation of ethanol
fumes and skin contact with ethanol.
Extinguish all open flames before refueling.
Never smoke or create sparks close to
ethanol.
! Do not use diesel to refuel vehicles with a
gasoline engine. Even small amounts of the
wrong fuel result in damage to the fuel
system and engine.
! Do not switch on the ignition if you
accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel lines.
Notify a qualified specialist workshop and
have the fuel tank and fuel lines drained
completely.
gasoline
Fuel grade
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
Flexible fuel vehicles (recognizable by the
sticker Premium gasoline or E85 only! on
the inside of the fuel filler flap) can be
refueled with E85. For further information
on flexible fuel, see "Fuel".
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.
i Only refuel with unleaded premium-grade
gasoline with a specified minimum octane
number of 91 (average value of 96 RON/
86 MON).
Usually you will find information about the
fuel grade on the pump. If you cannot find
the label on the gasoline pump, ask the gas
station staff.
C 300 and C 300 Sport with automatic
transmission: you can recognize flexible
fuel vehicles by the sticker Premium
gasoline or E85 only! on the inside of the
fuel filler flap.
You can find further information under
"Fuel" ( Y page 306), by consulting an
authorized Mercedes-Benz Center or
visiting http://www.mbusa.com (USA
only).
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Downhill gradients
! On long and steep gradients, you must
reduce the cargo on the brakes by shifting
to a lower gear in good time. This allows
you to take advantage of engine braking
and helps you to avoid overheating the
brakes and wearing them out excessively.
When you take advantage of engine
braking, a drive wheel may not turn for
some time, e.g. on a slippery road surface.
This could cause damage to the drive train.
Such damage is not covered by the
Mercedes-Benz warranty.
Heavy and light loads
GWarning
Depressing the brake pedal constantly results
in excessive and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
If the brakes have been subjected to a heavy
cargo, do not stop the vehicle immediately,
but drive on for a short while. This allows the
airflow to cool the brakes more quickly.
Wet roads
GWarning
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced. You have to depress the brake pedal
more firmly. Maintain a safe distance from
vehicles in front.
After driving on a wet road or having the
vehicle washed, brake firmly while paying
attention to the traffic conditions. This will
warm up the brake discs, thereby drying them
more quickly and protecting them against
corrosion.
Limited braking performance on salt
treated roadsGWarning
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in the
braking effect, resulting in a significantly
longer braking distance, which could lead to
an accident.
To avoid this danger, you should:
R occasionally brake carefully, without
putting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake discs.
Maintenance of 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 an authorized Mercedes-Benz
Center.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. This work
should be carried out at an authorized
Mercedes-Benz Center.
Only install brake pads and use brake fluid
recommended by Mercedes-Benz.
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GWarning
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that safe
braking is substantially impaired. This could
result in an accident.
! Vehicles with 4MATIC: a function or
performance test may only be carried out
on a two-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, the drive train
or the brake system may suffer damage.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition must be switched off
(SmartKey in position 0 or 1 in the ignition
lock or Start/Stop button in position 0 or
1 ) while the parking brake is being tested
on a brake dynamometer.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition system must be switched
off (SmartKey in position 0 or 1 in the
ignition lock or Start/Stop button in
position 0 or 1) when:
R testing the parking brake on a brake
dynamometer.
R you intend to have the vehicle towed with
the front axle raised.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
If your brake system is only subjected to
moderate loads, you should regularly test
your brake system's function by forcefully
depressing the brake pedal when driving at
high speed. This will give the brake pads
better grip.
GWarning
Make sure that you do not endanger other
road users when you apply the brakes.
You can find a description of Brake Assist
(BAS) on ( Y page 62).
High-performance brake system for
AMG vehicles
The high-performance brake system is only
installed on the C 63 AMG.
GWarning
New vehicle brake pads and discs, and
replacement brake pads and discs may take
several hundred miles of driving until they
provide optimum braking efficiency. Until that
time, you may need to use increased brake
pedal pressure while braking. Please be aware
of this and adjust your driving and braking
accordingly during this break-in period.
Excessive high-demand braking will cause
correspondingly high brake wear. Please be
attentive to the brake warning lamp in the
instrument cluster and brake condition
messages in the multifunction display.
Especially for high performance driving, it is
important to maintain and have the brake
system checked regularly.
The high-performance brake system is
designed for heavy loads. This may lead to
noise when braking. This will depend on:
R speed
R braking force
R environmental conditions, such as
temperature and humidity
The wear of individual components of the
brake system, such as the brake pads/linings
or brake discs, depends on the individual
driving style and operating conditions.
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