2016 MERCEDES-BENZ CLA COUPE engine overheat

There is a short delay before a change in outside
temperature appears in the multifunction dis-
play. Coolant temperature gauge
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.
The coolant temperature gauge is in the instru-
ment cluster on the right-hand side (Y page 32).
Under normal operating conditions and with the correct coolant level, the coolant temperature
may rise to 120 †.
At high outside temperatures and when driving
in mountainous terrain, the coolant temperature may rise to the end of the scale. Operating the on-board computer
Overview :
Multifunction display
; Right control panel
= Left control panel
X To activate the on-board computer: turn
the key to position 1in the ignition lock.
You can control the multifunction display and
the settings in the on-board computer using the buttons on the multifunction steering wheel.
Left control panel =
; R
Calls up the menu and menu bar 9
: Press briefly:
R Scrolls through lists
R Selects a submenu or function
R In the Audio Audio menu: selects the
previous or next station, when the preset list or station list is active,
or an audio track or video scene
R In the Tel Tel(telephone) menu:
switches to the phone book and
selects a name or telephone num-
ber Displays and operation
201On-board computer and displays Z

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

Display messages
Possible causes/consequences and
M
MSolutions Stop vehicle Shift
Stop vehicle Shift
to P Leave engine to P Leave engine
running running The automatic transmission has overheated.
X Drive on carefully.
If the display message disappears, the automatic transmission is
available again.
If the multifunction display still shows the display message:
X Stop the vehicle, paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 155).
X Wait until the automatic transmission has cooled down and the dis-
play message goes out. Auxiliary battery Auxiliary battery
malfunction malfunction The auxiliary battery for the automatic transmission is no longer being
charged.
X Consult a qualified specialist workshop.
X Until then, always shift the transmission to position Pbefore you
switch off the engine.
X Before leaving the vehicle, apply the electric parking brake. Clutch overheated
Clutch overheated
Avoid pulling away Avoid pulling away
If necessary, If necessary,
quickly quickly
release
releaseand
and
engage the clutch
engage the clutch The clutch is under considerable load and the permitted operating
temperature has been exceeded. A warning tone also sounds.
Avoid frequent pulling away and driving at walking pace over longer
distances.
X Stop the vehicle, paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 155).
X Leave the engine running.
The clutch is cooled more quickly with the engine running.
or X If possible, drive on at a steady speed.
X Remove your foot from the clutch pedal and do not allow the clutch
to slip.
The clutch may also cool down during the journey.
It may take several minutes for it to cool down. When the clutch has
cooled down, the display message disappears. The clutch is fully
operational again. For engine start For engine start
depress clutch depress clutch You have attempted to start the engine without depressing the clutch
pedal.
X Depress the clutch pedal.
X Restart the engine. The engine has stalled while pulling away, e.g. because the clutch
pedal was released too quickly.
X Depress the clutch pedal again.
The engine starts automatically.
X Slowly release the clutch pedal to pull away. Display
messages
243On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Trans. oil overhea‐
Trans. oil overhea‐
ted Drive on with ted Drive on with
care care Mercedes-AMG vehicles: the transmission oil has overheated.
Manual drive program Mand the temporarily active manual drive pro-
gram are no longer available. Engine power output is reduced.
X Allow the vehicle to cool down. 4matic currently
4matic currently
unavailable unavailable 4MATIC has overheated. The vehicle is only driven by the front wheels.
X Drive on.
The airflow cools 4MATIC more quickly.
When the display message goes out, 4MATIC is available again and
the vehicle is driven by all four wheels. 4matic inoperative 4matic inoperative 4MATIC is malfunctioning. The vehicle is only driven by the front
wheels.
X Consult a qualified specialist workshop. N The boot lid is open.
X Close the boot lid. M The bonnet is open.
A warning tone also sounds.
G WARNING
The open bonnet may then block your view when the vehicle is in
motion.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 155).
X Close the bonnet. Active bonnet mal‐ Active bonnet mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The active bonnet (pedestrian protection) is not active due to a mal-
function or because it has already been triggered.
X Consult a qualified specialist workshop. C At least one door is open. A warning tone also sounds.
X Close all doors. 244
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

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

i
Have the brake fluid regularly replaced at a
qualified specialist workshop and the replace-
ment confirmed in the Service Booklet. Coolant
Important safety notes G
WARNING
If antifreeze comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Let the engine cool down before you top up
the antifreeze. Make sure that antifreeze is
not spilled next to the filler neck. Thoroughly
clean the antifreeze from components before
starting the engine.
! Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine.
Further information on coolants can be found in the Mercedes-Benz Specifications for Ser-
vice Products, MB Specifications for Service
Products 310.1, e.g. on the Internet 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.
i Have the coolant regularly replaced at a
qualified specialist workshop and the replace-
ment confirmed in the Service Booklet.
Comply with the important safety precautions
for service products when handling coolant
(Y page 327).
The coolant is a mixture of water and corrosion
inhibitor/antifreeze concentrate. It is responsi-
ble for the following:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
If corrosion inhibitor/antifreeze concentrate is
present in the correct concentration, the boiling
point of the coolant during operation will be
approximately 130 †. The antifreeze concentrate/corrosion inhibitor
concentration 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 dissipa-
ted as effectively.
Mercedes-Benz recommends a coolant or cor-
rosion inhibitor/antifreeze concentrate in
accordance with
MB Specifications for Service Products 310.1.
i When the vehicle is first delivered, it is filled
with a coolant mixture that ensures adequate
antifreeze and corrosion protection.
i The coolant is checked at every mainte-
nance interval at a qualified specialist work-
shop. Windscreen washer system
Important safety notes G
WARNING
If windscreen washer concentrate comes into contact with hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury.
Make sure the windscreen washer concen-
trate does not come into contact with the filler neck.
! Only the washer fluids SummerFit and Win-
terFit can be mixed. Otherwise, the spraying
nozzles could become blocked.
Do not use distilled or de-ionised water. Other-
wise, the level sensor may give a false reading.
When handling washer fluid, observe the impor- tant safety notes on service products
(Y page 327).
At temperatures above freezing:
X Fill the washer fluid reservoir with a mixture of
water and washer fluid, e.g. MB SummerFit.
Mix 1 part MB SummerFit to 100 parts water.
At temperatures below freezing:
X Fill the washer fluid reservoir with a mixture of
water and washer fluid, e.g. MB WinterFit. 332
Service products and filling capacitiesTechnical data