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Problems with the fuel and fuel tank
Problem Possible causes/consequences and
M Solutions
Fuel is leaking from the
vehicle.
G
Risk of explosion or fire
The fuel line or the fuel tank is faulty.
X Turn the key to position 0(Y page 137) in the ignition lock
immediately and remove it.
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The engine does not
start. The fuel tank of a vehicle with a diesel engine has been run com-
pletely dry.
X Refuel the vehicle with at least five litres of diesel.
X Turn the ignition on for at least 10 seconds (Y page 137).
X Start the engine continuously for up to 10 seconds until it runs
smoothly.
If the engine does not start:
X Turn the ignition on again for approximately 10 seconds
(Y page 137).
X Start the engine again continuously for up to 10 seconds until
it runs smoothly.
If the engine does not start after three attempts:
X Consult a qualified specialist workshop. The fuel filler flap can-
not be opened. The fuel filler flap is not unlocked.
or
The key battery is discharged.
X
Unlock the vehicle (Y page 78).
or
X Unlock the vehicle using the emergency key element
(Y page 80). The fuel filler flap is unlocked, but the opening mechanism is jam-
med.
X
Consult a qualified specialist workshop. Refuelling
157Driving and parking Z
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Display messages Possible causes/consequences and
M Solutions
# The battery is no
tbeing charged.
Aw arning tone also sounds.
Possible causes are:
R a faulty alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attentio ntoroad and traf-
fic conditions, and switch off the engine.
X Open the bonnet.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is OK:
X Visit a qualified specialist workshop. 4
Check eng. oil
lev. when next
refuelling The engine oil level has dropped to a critical level.
Aw
arning tone also sounds.
X Chec kthe oil level (Y page 302).
X If necessary, top up the engine oil (Y page 303).
X Have the engine checked for leaks if the engine oil needs top-
ping up more often than usual. 8
Reserve fuel level The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. C There is only a very small amount of fuel in the fuel tank.
The auxiliary heating cannot be operated.
X
Refuel at the nearest filling station without fail. ¸
Replace
air cleaner Vehicles with a diesel engine: the engine air filter is dirty and must
be replaced.
X
Visit a qualified specialist workshop. !
Clean
the fuel fil‐
ter Vehicles with a diesel engine: there is water in the fuel filter. The
water must be drained off.
X
Visit a qualified specialist workshop. Display messages
255On-board computer and displays Z
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Engine
Problem Possible causes/consequences and
M Solutions
;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
There may be a fault, for example:
R
in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engin emay
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. Vehicles with a diesel engine: the fuel tan
khas been run dry
(Y page 157).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need no tbe
checked. 8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the
star
toft he scale. The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X
Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
X Apply the parking brake.
X Consult a qualified specialist workshop. 280
Warning and indicator lamps in the instrument clusterOn-board computer and displays
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regulations, as you could otherwise endanger
yourself and others.
Keep service products away from children.
To protect yourh ealth, do not allow service
products to come into contact with your eyes
or open wounds. See a doctor immediately if
any service product is swallowed. H
Environmental note
Dispose of service products in an environ-
mentally-responsible manner. Fuel
Important safety notes G
WARNING
Fuel is highly flammable. Fire, naked flames
and smoking are therefore prohibited when
handling fuels.
Switch off the engine and the auxiliary heating
before refuelling. G
WARNING
Do not come into contact with fuels.
It is hazardous to your health if your skin
comes into direct contact with fuels or you
breathe in fuel vapours.
Tank capacity Total capacity
C 180
25
C 250 25
C 220 CDI 25
C 250 CDI 25 59 l
Total capacity
C 350
25
AMG vehicles 66 l Reserve fuel in AMG vehi-
cles
Approx-
imately 14 l Reserve fuel in all other
models
Approx-
imately 8l !
Do not use petrol to refuel vehicles with a
diesel engine. Do not use diesel to refuel
vehicles with a petrol engine. Even small
amounts of the wrong fuel result in damage
to the fuel system and the engine.
For further information on refuelling and on
fuels, see (Y page 152).
Notes on fuel consumption The vehicle will use more fuel than usual in
the following situations:
R at very low outside temperatures
R in urban traffic
R for short journeys
R when towing a trailer
R in mountainous terrain
i Only for certain countries: you can find
the current consumption and emission val-
ues of your vehicle in the COC documents
(EU CERTIFICATE OF CONFORMITY).T hese
documents are delivered with your vehicle.
The consumption figures are in each case
based on the currently applicable version.
R for vehicles up to the EURO 4 standard
in accordance with EU Directive
RL 80 /1268 /EWG
R for vehicles complying with the EURO 5
standard or higher in accordance with
Regulation (EC) Nr. 715 /2007
Deviations from these values may occur
unde rnormal operating conditions.
! Do not use any fuel additives, as they can
cause malfunctions and engine damage.
25 BlueEFFICIENCY. 354
Service products and capacitiesTechnical data