2011 MERCEDES-BENZ C-CLASS SALOON coolant level

Problem Possible causes/consequences and
M Solutions
Vehicles with a petrol
engine:
The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X
Only depress the accelerator pedal slightly.
X Have the cause rectified immediately at a qualified specialist
workshop, e.g. a Mercedes-Benz Service Centre.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it. The coolant tempera-
ture display is showing
more than 120 †. The
coolant warning lamp
may also be lit and a
warning tone may
sound. The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X
Stop as soon as possible and allow the engine and the coolant
to cool down.
X Check the coolant level (Y page 324). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the engine radiator fan may be faulty.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
At coolant temperatures under 120 †, drive on to the nearest
qualified specialist workshop, e.g. to a Mercedes-Benz Service
Centre.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop-start traffic. Manual transmission
Important safety notes
G
WARNING
The movement of the pedals must not be
impaired in any way. Do not keep any objects
in the driver's footwell. Make sure that floor-
mats or carpets are correctly secured and
that there is sufficient clearance for the ped-
als.
Do not place several floormats on top of one
another. G
WARNING
Do not change down for additional engine
braking on a slippery road surface. This could
cause the drive wheels to lose their grip and
the vehicle could skid. This could cause you to lose control of your vehicle and cause an
accident.
Gear lever
Gear lever
!
Only engage gear when the clutch pedal
is depressed. 160
Manual transmissionDriving and parking

Useful information
i This Owner's Manual describes all models
and all standard and optional equipment
available to your vehicle at the time of pub-
lication of the Owner's Manual. Country-
specific deviations are possible. Please
note that your vehicle may not be equipped
with all features described. This also
applies to safety-relevan tsystems and
functions.
i Please read the information on qualified
specialist workshops (Y page 28).Important safety notes
You will find an illustration of the instrument
cluster in the "At a glance" section
(Y page 34). G
WARNING
Only use the on-board computer when road
and traffic conditions permit .You would oth-
erwise be distracted and unable to concen-
trate properly on driving, and could cause an
accident. G
WARNING
No messages will be displayed if either the
instrument cluster or the multifunction dis-
play is inoperative.
As a result, you will not be able to see infor-
mation about your driving conditions, such as
speed, outside temperature, warning and indi-
cator lamps, display messages or system fail-
ures. Driving characteristics may be impaired.
Adjust your driving style and vehicle speed
accordingly.
Contact a qualified specialist workshop
immediately. G
WARNING
The on-board computer only records and dis-
plays malfunctions and warnings from certain
systems. For this reason, you should always make sure that your vehicle is safe to use. You
could otherwise cause an accident by driving
an unsafe vehicle.
G
WARNING
The operating safety of your vehicle could be
impaired if maintenance work is carried out
incorrectly. This could cause you to lose con-
trol of your vehicle and cause an accident.
Moreover, the safety systems may no longer
be able to protect you or others as they are
designed to do.
Always have service work carried out at a
qualified specialist workshop. Displays and operation (4-button mul-
tifunction steering wheel)
Coolant temperature gauge
The coolant temperature gauge is in the
instrument cluster on the left-hand side.
Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 120 †.
The coolant temperature may rise to the top
end of the scale at high outside temperatures
and on long uphill stretches. Rev counter
The red band in the rev counter indicates the
engine's overrevving range.
! Do not drive in the overrevving range.
Doing so will damage the engine.
The fuel supply is interrupted to protec tthe
engine when the red band is reached. Outside temperature display
The outside temperature display is in the
instrument cluster (Y page 34).222
Displays and operation (4-button multifunction steering wheel)On-board computer and displays

X
To reset the trip meter: press and hold
the V until the standard display
appears.
X Press and hold the Cbutton until the
value has been reset. Trip computer
X Press the Vbutton on the steering
wheel repeatedly until the trip computer
appears. :
Distance
; Average speed
= Time
? Average fuel consumption
X To reset the trip computer: press and
hold the Cbutton on the steering wheel
until the values have been reset. Calling up the range
X Press the Vbutton on the steering
wheel repeatedly until the approximate
range appears.
The approximate range which can be covered
depends on the fuel level and your current
driving style .Ifthere is only a small amount
of fuel left in the fuel tank, the display shows
a vehicle being refuelled Cinstead of the
range. Switching the daytime driving lights
on/off
If you have activated the Day. driv.lights: function and the light switch is in the Ã
position, the daytime driving lights are
automatically switched on during daylight
hours when the engine is running. When it is
dark, the side lamps and the dipped-beam
headlamps are switched on automatically.
On vehicles with daytime driving lamps, the
factory setting is on .
If you want to change the setting for the Day. driv. lights: function, you have to turn
the key in the ignition lock to position 1.
X Press the Vbutton on the steering
wheel repeatedly until the Day. driv. lights: menu appears.
You will see the selected setting: on or
off .
X Press the WorX button to change
the setting. Displays and operation (12-button
multifunction steering wheel)
Coolant temperature gauge
The coolant temperature gauge is in the
instrumentc lusteront he left-hand side.
Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 120 †.
At high outside temperatures and when driv-
ing uphill, the coolant temperature may rise
to the end of the scale. Rev counter
The red band in the rev counter indicates the
engine's overrevving range.
! Do not drive in the overrevving range.
Doing so will damage the engine.
The fuel supply is interrupted to protect the
engine when the red band is reached. 226
Displays and operation (12-button multifunction steering wheel)On-board computer and displays

Engine (4-button multifunction steering wheel)
Display messages Possible causes/consequences and
M Solutions
Top up
coolant The coolant level is too low.
X
Top up the coolant, observing the warning notes when doing so
(Y page 324).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ?
Stop vehicle Sw.
eng. Off The coolant is too hot.
Aw
arning tone also sounds.
X Stop the vehicle immediately, paying attentio ntoroad and traf-
fic conditions, and switch off the engine.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Wait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately. The poly-V-belt may have torn.
X
Stop the vehicle immediately, paying attention to road 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 Wait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X Visit a qualified specialist workshop. ? The fan motor is faulty.
X
If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop-start traffic. 268
Display messagesOn-board computer and displays

Engine (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M Solutions
+
Top
up coolant See
Owner's Manual The coolant level is too low.
X
Top up the coolant, observing the warning notes when doing so
(Y page 324).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ?
Coolant Stop vehi‐
cle Switch engine
off The coolant is too hot.
Aw
arning tone also sounds.
X Stop the vehicle immediately, paying attentio ntoroad and traf-
fic conditions, and switch off the engine.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Wait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately. The poly-V-belt may have torn.
X
Stop the vehicle immediately, paying attention to road 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 Wait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X Visit a qualified specialist workshop. ? The fan motor is faulty.
X
If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop-start traffic. 270
Display messagesOn-board computer and displays

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 173).
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. 298
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be mal-
functioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 324).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop-start traffic. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
The engine is not being cooled sufficiently and may be damaged.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 324).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop-start traffic. Warning and indicator lamps in the instrument cluster
299On-board computer and displays Z

Example: vehicles with a diesel engine
X
Park the vehicle on a level surface.
To check the oil level with the engine at
normal operating temperature, switch the
engine off and wait for approximately five
minutes.
X Pull oil dipstick :outoft he oil dipstick
tube.
X Wipe off oil dipstick :.
X Slowly slide oil dipstick :into the guide
tube to the stop, and take it out again.
If the level is between MIN mark =and
MAX mark ;, the oil level is correct.
X If the oil level has dropped to MIN mark
= or below it, top up with
0.5 to 1.0 litres of engine oil.
Adding engine oil G
WARNING
If engine oil comes into contact with hot
engine parts, it may ignite and you could burn
yourself. Do not spill any engine oil on hot
engine parts. H
Environmental note
When topping up the oil, take care not to spill
any. If oil enters the soil or waterways, it is
harmful to the environment.
! 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 con-
verter. Have excess oil siphoned off. Example: engine oil cap
X
Turn cap :anti-clockwise and remove it.
X Top up the engine oil.
If the oil level is at or below the MIN mark
on the dipstick, top up with
0.5 to 1.0 litres of engine oil.
X Replace cap :on the filler neck and turn
clockwise.
Make sure that the cap locks into place
securely.
X Check the oil level again with the oil dip-
stick (Y page 323).
Further information on engine oil
(Y page 381). 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.
X Turn the key to position 2(Y page 153) in
the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 153).
X Check the coolant temperature display in
the instrument cluster. G
WARNING
The cooling system is pressurised. Therefore,
only unscrew the cap once the engine has
cooled down. The coolant temperature gauge 324
Engine compartmentMaintenance and care