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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.
! Never refuel vehicles with gasoline engine
with diesel fuel. Even small amounts of
diesel fuel will damage the fuel system and
engine. Damage resulting from the use of
non-approved fuels or fuel additives or
resulting from mixing gasoline with diesel
fuel is not covered by the Mercedes-Benz
Limited Warranty.
! If you have accidentally filled the tank
with incorrect or non-approved fuel, do not
switch on the ignition. Otherwise the
incorrect or non-approved fuel will get into
the fuel lines. The fuel system must be
drained completely. Contact an authorized
Mercedes-Benz Center to have the fuel
system drained completely.
! To prevent damage to the catalytic
converters, only use premium unleaded
gasoline in this vehicle.
Flexible Fuel Vehicles (identified by a label
reading Premium gasoline or E85 only!
on the fuel filler flap) may be fueled with
E85. For additional information, see
“Flexible Fuel Vehicles”.
Any noticeable irregularities in engine
operation should be repaired promptly.
Otherwise, excessive unburned fuel may
reach the catalytic converter, causing it to
overheat and potentially start a fire.
i Only use premium unleaded gasoline with
a minimum Posted Octane Rating of 91
(average of 96 RON/86 MON). Information
on gasoline quality can normally be found
on the fuel pump. Please contact gas
station personnel in case labels on the
pump cannot be found.
C 300 and C 300 Sport with automatic
transmission:
Flexible Fuel Vehicles are identified by a
label reading Premium gasoline or E85
only! on the fuel filler flap.
For more information on gasoline or E85,
see “Premium unleaded gasoline”
(Y page 354), see “Flexible Fuel Vehicles”
(Y page 355), see “Fuel requirements”
(Y page 354), or contact an authorized
Mercedes-Benz Center, or visit
www.mbusa.com (USA only).
Locking/unlocking the vehicle with the
SmartKey or KEYLESS-GO automatically
locks/unlocks the fuel filler flap.
iIn case the central locking system does
not release the fuel filler flap, see “Fuel filler
flap” (Y page 310).
The fuel filler flap is located on the right-hand
side of the vehicle towards the rear.
XTurn off the engine.
iLeaving the engine running and the fuel
filler cap open can cause the yellow engine
malfunction indicator lamp ; to
illuminate.
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For more information, see also “Practical
hints” ( Y page 305).XRemove the SmartKey from the starter
switch.
KEYLESS-GO: Open the driver’s door. This
puts the starter switch in position 0, same
as with the SmartKey removed from the
starter switch. The driver’s door then can
be closed again.XOpening: Press fuel filler flap : at the
point indicated by the arrow.XTurn fuel filler cap ; counterclockwise.XTake off fuel filler cap ;.
!
The fuel filler cap is tethered to the fuel
filler neck. Do not drop the cap. It could
damage the vehicle paint finish.
XPlace fuel filler cap ; in direction of arrow
into holder =.XFully insert filler nozzle unit and refuel.XOnly fill your tank until the filler nozzle unit
cuts out – do not top off or overfill .XClosing: Turn fuel filler cap ; clockwise
until it audibly engages.
i Close the fuel filler flap before locking the
vehicle. Otherwise the flap locking pin will
prevent closing the fuel filler flap.
XClose fuel filler flap :.
Check regularly and before a long trip
For information on quantities and
requirements of operating agents, see “Fuels,
coolants, lubricants, etc.” ( Y page 349).
Check the following:
R Engine oil level ( Y page 225)
R Tire inflation pressure ( Y page 232)
R Coolant level ( Y page 227)
R Vehicle lighting ( Y page 313)
R
Washer system and headlamp cleaning
system ( Y page 228)
R Brake fluid ( Y page 228)
Engine compartment
Hood
GWarning!
Do not pull the release lever while the vehicle
is in motion. Otherwise the hood could be
forced open by passing air flow.
This could cause the hood to come loose and
injure you and/or others.
Opening
GWarning!
Do not open the hood when the engine is
overheated. You could be seriously injured.
Observe the coolant temperature gauge to
determine whether the engine may be
overheated. If you see flames or smoke
coming from the engine compartment, move
away from the vehicle. Wait until the engine
has cooled. If necessary, call the fire
department.
GWarning!
You could be injured when the hood is open –
even when the engine is turned off.
Parts of the engine can become very hot. To
prevent burns, let the engine cool completely
before touching any components on the
vehicle. Comply with all relevant safety
precautions.
GWarning!
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running.
The radiator fan may continue to run for
approximately 30 seconds or may even
restart after the engine has been turned off.
Stay clear of fan blades.
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GWarning!
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components
(ignition coils, spark plug sockets, diagnostic
socket) of the ignition system
Rwith the engine running
Rwhile starting the engine
Rwhen the ignition is switched on and the
engine is turned manually
XPull hood lock release lever :.
The hood is unlocked.
! Never open the hood if the wiper arms are
folded forward away from the windshield.
Otherwise the windshield wipers or the
hood could be damaged.
XPush handle ; under the hood upwards.XPull up on the hood and then release it.
The hood will be held open at shoulder
height by gas-filled struts automatically.
ClosingGWarning!
When closing the hood, use extreme caution
not to catch hands or fingers. Be careful that
you do not close the hood on anyone.
Make sure the hood is securely engaged
before driving off. Do not continue driving if
the hood can no longer engage after an
accident, for example. The hood could
otherwise come loose while the vehicle is in
motion and injure you and/or others.
XLet the hood drop from a height of
approximately 8 in (20 cm).
XCheck to make sure the hood is fully
closed.
If you can raise the hood at a point above
the headlamps, then it is not properly
closed. Open it again and let it drop with
somewhat greater force.
Engine oil
The amount of oil your engine consumes will
depend on a number of factors, including
driving style. Increased oil consumption can
occur when the vehicle is new or the vehicle
is driven frequently at higher engine speeds.
Engine oil consumption checks should only
be made after the vehicle break-in period.
! Do not use any special lubricant additives,
as these may damage the drive assemblies.
Using special additives not approved by
Mercedes-Benz may cause damage not
covered by the Mercedes-Benz Limited
Warranty.
For further information contact an
authorized Mercedes-Benz Center.
Notes on checking engine oil level
When checking the oil level
Rthe vehicle must be parked on level ground
Rwith the engine at operating temperature,
the vehicle must have been stationary for
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at least 5 minutes with the engine turned
off
Rwith the engine not at operating
temperature, the vehicle must have been
stationary for at least 30 minutes with the
engine turned off
Checking engine oil level
XOpen the hood (Y page 224).XPull out oil dipstick :.XWipe oil dipstick : clean.XSlowly insert oil dipstick : fully into the
dipstick guide tube.
XPull out oil dipstick : again after
approximately 3 seconds to obtain
accurate reading.
The oil level is correct when it is between
lower (min) mark = and upper (max)
mark ; of oil dipstick :.
iAll models (except C 63 AMG):
The filling quantity between the upper and
lower marks on the oil dipstick is
approximately 2.1 US qt. (2.0 l).
C 63 AMG:
The filling quantity between the upper and
lower marks on the oil dipstick is
approximately 1.6 US qt. (1.5 l).
XIf necessary, add engine oil.
For more information on engine oil, see
“Fuels, coolants, lubricants etc.”
(Y page 349).
For information on messages in the
multifunction display concerning engine oil,
see the “Practical hints” section
(Y page 291).
Adding engine oil
! Only use approved engine oils and oil
filters required for vehicles with
Maintenance System. For a listing of
approved engine oils and oil filters, contact
an authorized Mercedes-Benz Center or
visit www.mbusa.com (USA only).
The following will result in engine or
emission control system damage not
covered by the Mercedes-Benz Limited
Warranty:
RUsing engine oils and oil filters of
specification other than those expressly
required for the Maintenance System.
RChanging of oil and oil filter at change
intervals longer than those called for by
the Maintenance System.
RUsing any oil additives.
All models (except C 63 AMG)
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C 63 AMG
XUnscrew filler cap : from filler neck.XAdd engine oil as required. Be careful not
to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
! Excess oil must be siphoned or drained
off. It could cause damage to the engine
and emission control system not covered
by the Mercedes-Benz Limited Warranty.
XScrew filler cap : back on filler neck.
For more information on engine oil, see the
“Technical data” section (Y page 349) and
(Y page 353).
Transmission fluid level
Vehicles with automatic transmission:
The transmission fluid level does not need to
be checked. If you notice transmission fluid
loss or gearshifting malfunctions, have an
authorized Mercedes-Benz Center check the
transmission.
Coolant level
The engine coolant is a mixture of water and
anticorrosion/antifreeze.
When checking the coolant level, the vehicle
must be parked on level ground, and the
coolant temperature must be below 158‡
(70†).
GWarning!
In order to avoid any potentially serious burns:
RUse 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 gauge indicates
that the coolant is overheated.
RDo not remove the cap on the coolant
expansion tank if the coolant temperature
is above 158‡ (70†). Allow the engine to
cool down before removing the cap. The
coolant expansion tank contains hot fluid
and is under pressure.
RUsing a rag, slowly open the cap
approximately 1/2 turn counterclockwise
to relieve excess pressure. If opened
immediately, scalding hot fluid and steam
will be blown out under pressure.
RDo not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts.
XUsing a rag, slowly open cap :
approximately 1/2 turn counterclockwise
to relieve excess pressure.
XContinue turning cap : counterclockwise
and remove it.
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The coolant level is correct if the level
Rfor cold coolant: reaches marking bar
= in coolant expansion tank ;
Rfor warm coolant: is approximately 0.6 in
(1.5 cm) higher
XAdd coolant as required.XScrew cap : back on and tighten it.
For more information on coolant, see the
“Technical data” section (Y page 351) and
(Y page 356).
Washer system and headlamp
cleaning system
GWarning!
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
! Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could result
in damage to the washer system/fluid
reservoir.
! Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can
damage the plastic lenses of the
headlamps.
! Do not use distilled or deionized water in
the washer fluid reservoir. Otherwise, the
washer fluid level sensor could be
damaged.
Fluid for the washer system and the headlamp
cleaning system is supplied from the washer
fluid reservoir.
During all seasons, use MB Windshield
Washer Concentrate “MB SummerFit”. Mix it
with water or premixed washer solvent/
antifreeze depending on the ambient
temperature (Y page 358).
XOpening washer fluid reservoir: Pull tab
of cap : upwards.
XRefill the washer fluid reservoir.XClosing washer fluid reservoir: Press
cap : onto filler hole until it engages.
For more information, see “Washer system
and headlamp cleaning system”
(Y page 352).
Brake fluid level
! If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum
mark or below, have the brake system
checked for brake pad thickness and leaks
immediately. Contact an authorized
Mercedes-Benz Center immediately. Do
not add brake fluid as this will not solve the
problem. For more information, see
“Practical hints”.
When checking the brake fluid level, the
vehicle must be parked on level ground.
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The brake fluid level is correct when it is
between lower mark (MIN) ; and upper
mark (MAX) : of the brake fluid reservoir.
Tires and wheels
Safety notes
Contact an authorized Mercedes-Benz Center
for information on tested and recommended
rims and tires for summer and winter
operation. They can also offer advice
concerning tire service and purchase.
GWarning!
Replace rims or tires with the same
designation, manufacturer and type as shown
on the original part. For further information
contact an authorized Mercedes-Benz Center.
If incorrectly sized rims and tires are
mounted, the wheel brakes or suspension
components can be damaged. Also, the
operating clearance of the wheels and the
tires may no longer be correct.
GWarning!
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can result
in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or
recommended by Mercedes-Benz, since
previous damage cannot always be
recognized on retreads. The operating safety
of the vehicle cannot be assured when such
tires are used.
GWarning!
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possible
damage to your vehicle has occurred, you
should turn on the hazard warning flashers,
carefully slow down, and drive with caution to
an area which is a safe distance from the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have the vehicle towed to the
nearest authorized Mercedes-Benz Center or
tire dealer for repairs.GWarning!
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
could lose control of the vehicle. Continued
driving with a flat tire or driving at high speed
with a flat tire will cause excessive heat build-
up and possibly a fire.
Important guidelines
R Only use sets of tires and rims of the same
type and make.
R Tires must be of the correct size for the rim.
R Break in new tires for approximately
60 miles (100 km) at moderate speeds.
R Regularly check the tires and rims for
damage. Dented or bent rims can cause tire
inflation pressure loss and damage to the
tire beads.
R If the vehicle is heavily loaded, check tire
inflation pressure and correct as required.
R Do not allow your tires to wear down too
far. Adhesion properties on wet roads are
sharply reduced at tread depths of less
than 1
/ 8 in (3 mm).
R When replacing individual tires, you should
mount new tires on the front wheels first
(on vehicles with same-sized wheels all
around).
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Recommended tire inflation pressureGWarning!
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Your vehicle is equipped with the Tire and
Loading Information placard located on the
driver’s door B-pillar (Y page 238).
The tire inflation pressure should be checked
regularly. Only adjust the tire inflation
pressure on cold tires. The tires can be
considered cold if the vehicle has been
parked for at least 3 hours or driven less than
1 mile (1.6 km). Depending on the ambient
temperature, the driving speed and the tire
load, the tire temperature changes. When the
tire temperature changes by 18‡ (10†), the
tire inflation pressure will change by
approximately 1.5 psi (0.1 bar). Keep this in
mind when checking tire inflation pressure on
warm tires and adjust the tire pressure only
if the tire inflation pressure is too low for the
current operating conditions. If you check the
tire inflation pressure when the tires are
warm, the reading will be higher than the cold
reading. This is normal. Do not let air out to
match the specified cold tire inflation
pressure. Otherwise, the tire will be
underinflated.
Follow recommended cold tire inflation
pressures listed on Tire and Loading
Information placard on the driver’s door
B-pillar.
Keeping the tires properly inflated provides
the best handling, tread life and riding
comfort.
In addition to the Tire and Loading
Information placard on the driver’s door
B-pillar, also consult the tire inflation
pressure label on the inside of the filler flap
for any additional information pertaining to
special driving situations. For more
information, see “Important notes on tire
inflation pressure” (Y page 231).
iData shown on Tire and Loading
Information placard example are for
illustration purposes only. Tire data are
specific to each vehicle and may vary from
data shown in the following illustration.
Refer to Tire and Loading Information
placard on vehicle for actual data specific
to your vehicle.
The Tire and Loading Information placard lists
the recommended cold tire inflation
pressures : for maximum loaded vehicle
weight. The tire inflation pressures listed
apply to the tires installed as original
equipment.
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