2012 MERCEDES-BENZ C-Class SEDAN Cooling

iThe cooling with air dehumidification
function uses refrigerant R134a. This
coolant does not contain
chlorofluorocarbons, and therefore does
not damage the ozone layer.
Activating/deactivatingXTo activate: 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
When you press the ¿ button, the
indicator lamp in the button flashes three
times or remains off. You can no longer switch
on 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.
i 3-zone automatic climate control: when
automatic mode is activated, you can
select a climate mode setting
( Y page 127).
XTo switch off: 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.
Adjusting the climate mode settings
(AIR FLOW)
This function is only available with 3-zone
automatic climate control.
The climate mode settings are especially
effective at high temperatures.
You can select the following climate mode
settings in automatic mode:
FOCUShigh airflow that is set slightly
coolerMEDIUMmedium airflow, standard settingDIFFUSElow airflow that is set slightly
warmer and with less draftXTurn the SmartKey to position 2 in the
ignition lock.XPress the à button.XPress the ñ button repeatedly until the
desired climate mode appears in the
display.Operating the climate control system127Climate controlZ

XTurn the SmartKey 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.
i
You can use automatic climate control to
set the airflow in the rear compartment
separately.
Switching the ZONE function on/off
This function is only available in vehicles for
Canada.
XTo switch on: press the á button.
The indicator lamp in the á button lights
up.
Dual-zone automatic climate control: the
temperature setting for the driver's side is
not adopted for the front-passenger side.
3-zone automatic climate control: the
temperature setting for the driver's side is
not adopted for the front-passenger side
and the rear compartment.
When the buttons for temperature, airflow or
air distribution are activated, the temperature
setting for the driver's side is not adopted for
the other climate control zones.
XTo switch off: press the á button.
The indicator lamp in the á button goes
out.
Dual-zone automatic climate control: the
temperature setting for the driver's side is
adopted for the front-passenger side.3-zone automatic climate control: the
temperature setting for the driver's side is
adopted for the front-passenger side and
the rear compartment.
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 13
R high temperature 13
R air distribution to the windshield and
front side windows
R air-recirculation mode offXTo switch off: 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 temperature control : or B
clockwise or counter-clockwise
( Y page 123), ( Y page 125).13
Depending on the outside temperature.Operating the climate control system129Climate controlZ

orXPress the K or I button.
MAX COOL maximum cooling
The MAX COOL function is only available in
vehicles for the USA.
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 on
XTo 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 129).
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 defroster
Activating/deactivatingGWARNING
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 defroster 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 defroster 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
defroster
The rear window defroster 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 defroster 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.
The operation of air-recirculation mode is the
same for all control panels.
GWARNING
Fogged windows impair visibility,
endangering you and others. If the windows
130Operating the climate control systemClimate control

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
up.
i In the event of high pollution levels 14
or at
high outside temperatures, air-
recirculation mode is automatically
activated. 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 switch off: press the g button.
The indicator lamp in the g button goes
out.
i Air-recirculation mode deactivates
automatically:
R after approximately five minutes if
outside temperatures are less than about
41 ‡ (5 †)
R after approximately five minutes if
cooling with air dehumidification is
deactivated
R after approximately 30 minutes if outside
temperatures are over about
41 ‡ (5 †)
Activating/deactivating the residual
heat function
The residual heat function is only available in
vehicles for Canada with automatic climate
control.
It is possible to make use of the residual heat
of the engine to continue heating the
stationary vehicle for up to 30 minutes after
the engine has been switched off. The heating
time depends on the temperature that has
been set.
i The blower will run at a low speed
regardless of the airflow setting.
i If you activate the residual heat function
at high temperatures, only the ventilation
will be activated. The blower runs at
medium speed.XTurn the SmartKey to position 0 in the
ignition lock or remove it.XTo activate: press the Ì button.
The indicator lamp in the Ì button lights
up.XTo switch off: press the Ì button.
The indicator lamp in the Ì button goes
out.
i Residual heat is deactivated
automatically:
R after about 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R if the coolant temperature is too low
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
14 Automatic climate control only.Setting the air vents131Climate controlZ

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:
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 grille
in the vehicle interior.
i For 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 ventsXTo open/close: turn thumbwheel = to the
left or right.
i Side window defroster vent : is never
completely shut, even if side air vent ; is
shut.
Setting the glove box air vent
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 vent132Setting the air ventsClimate control

Display messagesPossible causes/consequences and M Solutionsb
AUTO Lamp Function
InoperativeThe light sensor is defective.XVisit a qualified specialist workshop.b
Switch Off LightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to c or à .Adaptive Highbeam
Assist InoperativeAdaptive Highbeam Assist is faulty.XVisit a qualified specialist workshop.Adaptive Highbeam
Assist Currently
Unavailable See
Operator's ManualAdaptive Highbeam Assist is deactivated and temporarily
inoperative. Possible causes are:
R the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.XClean the windshield.
If the system detects that the camera is fully functional again, the
Adaptive Highbeam Assist Now Available display message
is shown.
Adaptive Highbeam Assist is operational again.
Engine
Display messagesPossible causes/consequences and M Solutions+
Check Coolant
Level See
Operator's ManualThe coolant level is too low.XAdd coolant, observing the warning notes when doing so
( Y page 280).XIf coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop.GWARNING
Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may burn
if it comes into contact with hot engine parts. You could be seriously burned.
! The coolant level is too low. Avoid making long journeys with too little coolant in the cooling
system. The engine will otherwise be damaged.
The display messages and the corresponding symbol that indicate that the coolant level is
too low must not be ignored.
Display messages225On-board computer and displaysZ

yourself. Do not spill any engine oil on hot
engine parts.HEnvironmental note
When adding oil, take care not to spill any. If
oil enters the soil or waterways, it is harmful
to the environment.
! Use only engine oils and oil filters that
have been approved for vehicles equipped
with a service system. A list of the engine
oils and oil filters tested and approved in
accordance with the Mercedes-Benz
Specifications for Service Products can be
called up by visiting http://
www.mbusa.com (USA only). More
information about tested and approved
engine oils and oil filters is available from
any authorized Mercedes-Benz Center.
Damage to the engine or exhaust system is
caused by the following:
R using engine oils and oil filters which
have not been specifically approved for
the service system.
R replacing the engine oil or oil filter after
the replacement interval required by the
service system has elapsed
R using engine oil additives.
! Do not add too much oil. If the oil level is
above the "max" mark on the dipstick, too
much oil has been added. This can lead to
damage to the engine or the catalytic
converter. Have excess oil siphoned off.
Example: engine oil cap
XTurn cap : counterclockwise and remove
it.XAdd engine oil.
If the oil level is at or below the MIN mark
on the oil dipstick,
add 0.55 to 1.1 US qt (0.5 to 1.0 l) engine
oil.XReplace cap : on the filler neck and turn
clockwise.
Ensure that the cap locks into place
securely.XCheck the oil level again with the oil
dipstick ( Y page 279).
Further information on engine oil
( Y page 349).
Checking and adding other service
products
Checking the coolant level
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
XTurn the SmartKey to position
2 (Y page 137) in the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 137).XCheck the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †).GWARNING
In order to avoid any potentially serious burns:
R use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system, or
if the coolant temperature display indicates
that the coolant is overheated.
R do not remove the pressure cap on the
coolant reservoir if the coolant temperature
is above 158 ‡ (70 †). Allow the engine to
cool down before removing the cap. The
280Engine compartmentMaintenance and care

Capacities
Missing values were not available at time of going to print.ModelCapacityFuel, coolant,
lubricants, etc.Engine oil and
filterC 2505.8 US qt (5.5 l)Approved engine
oilsC 250 4MATIC 31
C 300 4MATIC7.4 US qt (7.0 l)C 350
C 350 4MATIC 31C 63 AMG329.0 US qt (8.5 l)Cooling systemC 250Approximately 7.6 US qt
(7.2 l)MB 325.0 or
MB 326.0
antifreeze/
corrosion inhibitorC 250 4MATIC 31
C 300 4MATICApproximately 8.9 US qt
(8.4 l)C 350
C 350 4MATIC 31C 63 AMGApproximately 12.4 US qt
(11.7 l)Tank capacityC 25015.6 US gal (59.0 l)Premium-grade
unleaded gasoline
(at least 91 octane,
average value
between 96 RON/
86 MON)All models except
C 25017.4 US gal (66.0 l)ReserveAll models except
AMG vehiclesApproximately 2.1 US gal
(8.0 l)C 63 AMGApproximately 3.7 US gal
(14.0 l)Windshield/
headlamp
cleaning
systemC 250
C 350
C 350 4MATIC 31
C 63 AMG3.7 US qt (3.5 l)MB windshield
washer
concentrate 33
( Y page 351)
Mixing ratio for
washer fluid
( Y page 351)C 250 4MATIC 31
C 300 4MATIC6.3 US qt (6.0 l)31 Canada only.
32 Including external oil cooler.
33 Mixed with water or premixed washer fluid with antifreeze protection.346Service products and capacitiesTechnical data