2013 MERCEDES-BENZ CLA-CLASS engine overheat

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos-
sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: ( Y page 24).
Important safety notes
GWARNING
Operating the integrated information systems
and communications equipment in the vehicle
while driving will distract you from traffic con-
ditions. You could then lose control of the
vehicle. There is a risk of an accident.
Only operate these devices if road traffic con-
ditions permit. If you are unsure about the
surrounding conditions, pull over to a safe
location and make entries only while the vehi-
cle is stationary.
GWARNING
If the instrument cluster has failed or mal-
functioned, you may not recognise function
restrictions relevant to safety. The operating
safety of your vehicle may be impaired. There
is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
You must observe the legal requirements for
the country in which you are currently driving
when operating the on-board computer.
The on-board computer only shows messages
or warnings from certain systems in the mul-
tifunction display. You should therefore make
sure your vehicle is operating safely at all
times. Otherwise, a vehicle that is not oper-
ating safely may cause an accident.
For an overview, see the instrument panel
illustration ( Y page 30).
Displays and operation
Instrument cluster lighting
The lighting in the instrument cluster, in the
displays and the controls in the vehicle inte-
rior can be adjusted using the brightness con-
trol knob.
The brightness control knob is on the bottom
left of the instrument cluster ( Y page 30).
XTurn the brightness control knob clockwise
or anti-clockwise.
If the light switch is set to Ã, T or
L , the brightness is dependant upon
the brightness of the ambient light.
i The light sensor in the instrument cluster
automatically controls the brightness of
the multifunction display.
In daylight, the displays in the instrument
cluster are not illuminated.
Coolant temperature gauge
GWARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking
service products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in
the engine compartment, leave the bonnet
closed and notify the fire brigade.
The coolant temperature gauge is in the
instrument cluster on the right-hand side.
Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 120 †.
208Displays and operationOn-board computer and displays
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Display messagesPossible causes/consequences and M Solutions?
Coolant Stop car,
turn engine offThe coolant is too hot.
A warning tone also sounds.GWARNING
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
There is a risk of injury.
XStop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.XSecure the vehicle against rolling away ( Y page 162).XWait until the engine has cooled down.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.XDo not start the engine again until the display message goes out
and the coolant temperature is below 120 †. The engine may
otherwise be damaged.XPay attention to the coolant temperature display.XIf the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 120 †.
#The battery is not being charged.
A warning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronicsXStop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.XOpen the bonnet.XCheck whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
XConsult a qualified specialist workshop.
If the poly-V-belt is OK:
XVisit a qualified specialist workshop immediately.Display messages241On-board computer and displaysZProCarManuals.com

Display messagesPossible causes/consequences and M SolutionsTransmission mal‐
functionThe automatic transmission is malfunctioning.XVisit a qualified specialist workshop.Transmission mal‐
function StopThe automatic transmission is malfunctioning.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 162).XConsult a qualified specialist workshop.Stop vehicle Shift
to P Leave engine
runningThe automatic transmission has overheated.XDrive on carefully.
If the display message disappears, the automatic transmission
is available again.
If the display message continues to be displayed:
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 162).XWait until the automatic transmission has cooled off and the
display message goes out.NThe boot lid is open.XClose the boot lid.MThe bonnet is open.
A warning tone also sounds.GWARNING
The open bonnet may then block your view when the vehicle is in
motion.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the electric parking brake.XClose the bonnet.Active bonnet mal‐
function See Own‐
er's ManualThe active bonnet (pedestrian protection) is not active due to a
malfunction or because it has already been triggered.XVisit a qualified specialist workshop.CAt least one door is open. A warning tone also sounds.XClose all doors.252Display messagesOn-board computer and displays
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ProblemPossible 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.XObserve the additional display messages in the multifunction
display.XStop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.XSecure the vehicle against rolling away ( Y page 162).XLeave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.XCheck the coolant level and top up the coolant ( Y page 285).
Observe the warning notes as you do so.XIf you have to top up the coolant frequently, have the engine
cooling system checked.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.XDo not start the engine again until the coolant temperature is
below 120 †. The engine may otherwise be damaged.XDrive to the nearest qualified specialist workshop.XAvoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain 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.GWARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam from an overheated engine can cause serious burns which
can occur just by opening the bonnet.
This poses a risk of injury.
XObserve the additional display messages in the multifunction
display.XStop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.XSecure the vehicle against rolling away ( Y page 162).Warning and indicator lamps in the instrument cluster263On-board computer and displaysZProCarManuals.com

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos-
sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: ( Y page 24).
Engine compartment
Bonnet
Important safety notes
GWARNING
An unlocked bonnet may open while driving
and block your view. There is a risk of an acci-
dent.
Never unlock the bonnet while driving.
GWARNING
When being opened and closed, the bonnet
may suddenly fall into the closed position.
There is a risk of injury to persons in the range
of movement of the bonnet.
Open and close the bonnet only when nobody
is in the range of movement.
GWARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the following compo-
nents.
GWARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking
service products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in
the engine compartment, leave the bonnet
closed and notify the fire brigade.GWARNING
There are parts in the engine compartment
that move. Certain components may continue
to run even if the ignition is switched off or
may suddenly start again, e.g. the radiator
fan. There is a danger of injury.
If you need to access the engine compart-
ment:
R switch off the ignition
R never enter the danger area of moving com-
ponents, e.g. the rotation area of the fan
R keep items of clothing away from moving
parts
GWARNING
The ignition system and the fuel injection sys-
tem operate with a high voltage. If you touch
the live components, you could receive an
electric shock. There is a danger of injury.
Never touch components of the ignition sys-
tem or the fuel injection system when the
ignition is switched on.
Active bonnet (pedestrian protection)
Operating principle
! Once triggered, an active bonnet must be
reset at a qualified specialist workshop,
e.g. a Mercedes-Benz Service Centre. The
active bonnet function will then be availa-
ble again. The additional pedestrian pro-
tection provided by the active bonnet will
then be restored.
The active bonnet is only available in certain
countries.
The active bonnet can reduce the risk of injury
to pedestrians in certain accident situations.
282Engine compartmentMaintenance and care
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for Service Products, MB Specifications for
Service Products 310.1, e.g. on the Inter-
net at http://bevo.mercedes-benz.com.
Or contact a qualified specialist workshop.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
overheating.
! The engine cooling system is filled with
coolant, which must be renewed after
15 years or after 250,000 kilometres at the
latest.
When handling coolant, observe the impor-
tant safety notes on service products
( Y page 336).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following tasks:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
If antifreeze/corrosion inhibitor is present in
the correct concentration, the boiling point of
the coolant during operation will be approx-
imately 130 †.
The antifreeze/corrosion inhibitor concentra-
tion in the engine cooling system should:
R be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -37 †.
R not exceed 55% (antifreeze protection
down to -45 †). Heat will otherwise not be
dissipated as effectively.
If the vehicle has lost coolant, top it up with
equal amounts of water and antifreeze/cor-
rosion inhibitor.
Mercedes-Benz recommends an antifreeze/
corrosion inhibitor concentrate in accord-
ance with MB Specifications for Service Prod-
ucts 310.1.
The coolant is checked at every maintenance
interval at a qualified specialist workshop.i When the vehicle is first delivered, it is fil-
led with a coolant mixture that ensures
adequate antifreeze and corrosion protec-
tion.
Windscreen washer system and head-
lamp cleaning system
Important safety notes
GWARNING
Windscreen washer concentrate is highly
flammable. If it comes into contact with hot
engine components or the exhaust system it
could ignite. There is a risk of fire and injury.
Make sure that no windscreen washer con-
centrate is spilled next to the filler neck.
! Only use washer fluid that is suitable for
plastic lamp lenses, e.g. MB SummerFit or
MB WinterFit. Unsuitable washer fluid
could damage the plastic lenses of the
headlamps.
! Do not use distilled or de-ionised water in
the washer fluid reservoir. Otherwise, the
level sensor may be damaged.
! Only the washer fluids SummerFit and
WinterFit can be mixed. Otherwise, the
spraying nozzles could become blocked.
When handling washer fluid, observe the
important safety notes on service products
( Y page 336).
At temperatures above freezing:
XFill the washer fluid reservoir with a mixture
of water and washer fluid, e.g. MB Sum-
merFit.
Mix 1 part MB SummerFit to 100 parts water.
342Service products and capacitiesTechnical data
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