2016 MERCEDES-BENZ CLA COUPE radiator

Problem
Possible causes/consequences and
M
MSolutions The engine does not
start. The starter motor
is turning audibly. The
reserve fuel warning
lamp is lit and the fuel
gauge display shows 0. The fuel tank is empty.
X Refuel the vehicle. The engine does not
start. The starter motor
is not turning audibly. The on-board voltage is too low because the battery is too weak or
discharged.
X Jump-start the vehicle (Y page 301).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to excessively high thermal load.
X Allow the starter motor to cool down for approximately two minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop. Vehicles with a petrol
engine:
The engine is not running
smoothly and is misfir-
ing. The engine electronics or a mechanical component of the engine
management system are/is malfunctioning.
X Depress the accelerator pedal only slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it.
X Have the cause rectified immediately at a qualified specialist work-
shop. The coolant temperature
display is showing more
than 120 †. The coolant warning lamp may also
be on and a warning tone
may sound. The coolant level is too low. The coolant is too hot and the engine is not
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 283). 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 not being cooled sufficiently.
X If the coolant temperature is below 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 in moun-
tainous terrain and stop-start traffic. 140
DrivingDriving and parking

Display messages
Possible causes/consequences and
M
MSolutions ?
Coolant Stop vehi‐ Coolant Stop vehi‐
cle Switch engine cle Switch engine
off off The coolant is too hot.
A warning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine has
overheated can cause any fluids that may have leaked into the engine compartment to catch fire.
In addition, steam from an overheated engine can cause serious
burns, which can occur just by opening the bonnet.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 155).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not blocked,
e.g. by frozen slush.
X Do not start the engine again until the display message goes out and
the coolant temperature is below 120 †. The engine may otherwise be damaged.
X Pay attention to the coolant temperature gauge.
If the temperature increases again:
X Consult a qualified specialist workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 120 †. #
See Owner's Manual See Owner's Manual The battery is no longer being charged.
A warning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
! Do not continue driving. The engine could otherwise overheat.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 155).
X Consult a qualified specialist workshop. 232
Display
messagesOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
M Solutions ?
N
The red coolant warning lamp lights up while the engine is running.
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 malfunctioning.
The coolant is too hot and the engine is not being cooled sufficiently.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Secure the vehicle against rolling away (Y page 155).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and top up the coolant, making sure to observe the
warning notes (Y page 283).
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 Do not start the engine again until the coolant temperature is below 120 †. The
engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-start traffic. ?
N
The red coolant warning lamp lights up while the engine is running. 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.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine has overheated
can cause any fluids that may have leaked into the engine compartment to catch fire.
In addition, steam from an overheated engine can cause serious burns, which can
occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Secure the vehicle against rolling away (Y page 155).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and top up the coolant, making sure to observe the
warning notes (Y page 283).
X If you have to top up the coolant frequently, have the engine cooling system
checked. 256
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions 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 below 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 in mountainous terrain
and stop-start traffic. Driving systems
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ·
N
The red distance warning lamp lights up while the vehicle is in motion.
The distance to the vehicle in front is too small for the speed selected.
X Increase the distance. ·
N
The red distance warning lamp lights up while the vehicle is in motion. A warning
tone also sounds.
You are approaching a vehicle or a stationary obstacle in your line of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to brake or take
evasive action.
Further information on the distance warning function of Active Brake Assist
(Y page 67). Warning and indicator lamps in the instrument cluster
257On-board computer and displays Z

Engine compartment
Bonnet
Important safety notes G
WARNING
An unlocked bonnet may open up when the
vehicle is in motion and block your view. There is a risk of an accident.
Never unlock the bonnet when driving. Before
every trip, ensure that the bonnet is locked. G
WARNING
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. G
WARNING
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 ser-
vice 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. G
WARNING
There are moving components in the engine
compartment. Certain components may con-
tinue to move or suddenly move again even
after the ignition has been switched off, e.g.
the radiator fan. There is a risk of injury.
If you have to carry out work in the engine
compartment:
R switch off the ignition
R never touch the dangerous areas surround-
ing moving components, e.g. the rotation
area of the fan R
remove jewellery and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts. G
WARNING
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
! An active bonnet that had been triggered
must be repaired at a qualified specialist
workshop. The active bonnet function will
then be available again. The additional pedes- trian protection provided by the active bonnet will then be restored.
The active bonnet is available only in certain
countries.
The active bonnet can reduce the risk of injury to
pedestrians in certain accident situations. Rais- ing the active bonnet increases the clearance tohard components, such as the engine.
If the active bonnet has been triggered, it is
raised at the rear in the area around the hinge byapproximately 60 mm.
For the drive to the workshop, reset the trig-
gered active bonnet yourself. If the active bon-
net has been triggered, pedestrian protection
may be limited.
Resetting G
WARNING
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 components descri- bed in the following. 280
Engine compartmentMaintenance and care

X
With your hand flat, push down active bon-
net :in the area around the hinges on both
sides (arrows) until you feel it engage.
If you can raise the active bonnet slightly at the
rear in the area around the hinges, it is not
engaged correctly. Repeat the step.
If the bonnet can then still be raised, drive
directly to a qualified specialist workshop. Do
not drive faster than 100 km/h.
Opening the bonnet G
WARNING
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 components descri- bed in the following. G
WARNING
When the bonnet is open, and the windscreen wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windscreen wipers and
the ignition before opening the bonnet.
! Make sure that the windscreen wipers are
not folded away from the windscreen. Other-
wise, you could damage the windscreen wip-
ers or the bonnet. X
Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. X
Reach into the gap between the bonnet and
the radiator trim and press bonnet catch
lever ;to the left.
X Raise the bonnet. X
Pull support strut ?out of bracket A.
X Lift up support strut ?and insert it into yel-
low retaining clip =. Engine compartment
281Maintenance and care Z

Closing the bonnet
X
Raise the bonnet slightly and, at the same
time, remove support strut ?from yellow
retaining clip =.
X Swing support strut ?down and press it into
bracket Auntil it engages.
X Lower the bonnet and let it fall from a height
of approximately 20 cm.
X Check that the bonnet has engaged properly.
If the bonnet can be raised slightly, it is not
properly engaged. Do not press the bonnet
closed. Open the bonnet again and close it
with a little more force. Engine oil
General notes Depending on your driving style, the vehicle
consumes up to 0.8 litres of oil per 1,000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently drive
at high engine speeds.
Depending on the engine, the oil dipstick may be installed at a different location.
When checking the oil level:
R park the vehicle on a level surface
R the engine should be switched off for approx-
imately five minutes if the engine is at normal
operating temperature.
R if the engine is not at normal operating tem-
perature, e.g. if the engine was only started
briefly, wait approximately 30 minute sbefore
carrying out the measurement
Checking the oil level using the oil dip-
stick G
WARNING
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 components descri- bed in the following. Example: vehicles with a petrol engine
Example: vehicles with a diesel engine
(except the CLA 180 d model)
Example: CLA 180 d model
X All models except CLA 180 d: pull out oil
dipstick :.
X The CLA 180 d model: release the oil filler
cap and pull it out together with integrated 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, top up with 1.0 lof engine oil. 282
Engine compartmentMaintenance and care

Topping up engine oil
G
WARNING
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 components descri- bed in the following. G
WARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil does not spill out
over the filler neck. Allow the engine to cool
down and thoroughly clean the components
that have come into contact with engine oil
before you start the engine. 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.
! Use only engine oils and oil filters that are
approved for vehicles with a service system. A
list of the engine oils and oil filters that have
been tested and approved in accordance with Mercedes-Benz Specifications for Service
Products is available at any Mercedes-Benz
Service Centre.
The following cause engine failure or damage
to the exhaust system:
R Use of engine oils and oil filters that have
not been expressly approved for the service system
R Replacement of engine oil and oil filter after
the replacement interval specified by the
service system has expired
R Use of engine oil additives
! Do not add too much oil. Topping up with too
much engine oil can result in damage to the
engine or to the catalytic converter. Have
excess engine oil siphoned off. Example: engine oil filler 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 oil dipstick, top up with 1.0 lof engine oil.
X Replace cap :on the filler neck and turn
clockwise.
Make sure that the cap locks securely into
place.
X Check the oil level again with the oil dipstick
(Y page 282).
Further information on engine oil (Y page 330). Checking and adding other service
products
Checking the coolant level G
WARNING
The cooling system is pressurised, particu-
larly when the engine is warm. If you open the cap, you could be scalded if hot coolant
sprays out. There is a risk of injury.
Let the engine cool down before you open the
cap. Wear gloves and eye protection. Open
the cap slowly to release the pressure.
! The coolant level must only be checked and
corrected when the engine has cooled down
(coolant temperature under 40 †). Checking
the coolant level when the coolant tempera-
ture is over 40 † can lead to damage to the
engine or engine cooling system. Engine compartment
283Maintenance and care Z