2015 MERCEDES-BENZ A-CLASS HATCHBACK cooling

X
To activate: press theábutton.
The indicator lamp in the ábutton lights
up.
The temperature setting for the driver's
side is not adopted for the front-passenger side.
X To deactivate: press theábutton.
The indicator lamp in the ábutton goes
out.
The temperature setting for the driver's
side is adopted for the front-passenger
side. Demisting the windscreen
General notes You can use this function to defrost the wind-
screen or to demist the inside of the wind-
screen and the side windows.
i You should only select the "Windscreen
demisting" function until the windscreen is clear again.
Switching the "Windscreen demisting"
function on/off X
Turn the key to position 2in the ignition
lock (Y page 157).
X To activate: press the¬button.
The indicator lamp in the ¬button lights
up.
The climate control system switches to the
following functions:
R high airflow
R high temperature
R air distribution to the windscreen and
front side windows
R air-recirculation mode off
i The "Windscreen demisting" function
automatically sets the blower output to the optimum demisting effect. As a result, the
airflow may increase or decrease automat-
ically after the ¬button is pressed. i
You can adjust the blower output man-
ually while the "Windscreen demisting"
function is in operation:
R Air-conditioning system: turn airflow
control Aanti-clockwise or clockwise
(Y page 137).
R THERMOTRONIC automatic climate con-
trol: press the óorô button.
X To deactivate: press the¬button.
The indicator lamp in the ¬button goes
out. The previous settings are reactivated.
Air-recirculation mode remains deactiva-
ted.
or
X THERMOTRONIC automatic climate con-
trol: press the Ãbutton.
The indicator lamp in the ¬button goes
out. Airflow and air distribution are set to
automatic mode.
or
X Air-conditioning system: turn temperature
control :anti-clockwise or clockwise
(Y page 137).
THERMOTRONIC automatic climate con-
trol: turn temperature control :orE anti-
clockwise or clockwise (Y page 139). Demisting the windows
Windows misted up on the inside Air-conditioning system
X Activate the ¿"Cooling with air dehu-
midification" function.
X If the windows continue to mist up, activate
the ¬ "Windscreen demisting" function.
i You should only select this setting until
the windscreen is clear again. 144
Operating the climate control systemClimate control

THERMOTRONIC automatic climate con-
trol
X Activate the ¿"Cooling with air dehu-
midification" function.
X Activate automatic mode Ã.
X If the windows continue to mist up, activate
the ¬ "Windscreen demisting" function.
i You should only select this setting until
the windscreen is clear again.
Windows misted up on the outside X
Activate the windscreen wipers.
X Set the air distribution to PorO.
i You should only select this setting until
the windscreen is clear again. Rear window heating
General notes The rear window heating has a high current
draw. You should therefore switch it off as
soon as the window is clear. It otherwise
switches off automatically after several
minutes.
If the battery voltage is too low, the rear win-
dow heating may switch off.
Switching on/off X
Turn the key to position 2in the ignition
lock (Y page 157).
X Press the ¤button.
The indicator lamp in the ¤button lights
up or goes out. Operating the climate control system
145Climate control

Problems with the rear window heating
Problem
Possible causes/consequences and
M
MSolutions The rear window heat-
ing has switched off
prematurely or cannot
be activated. The battery has not been sufficiently charged.
X Switch off any consumers that are not required, e.g. reading
lamps, interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window heat- ing can be activated again. Switching air-recirculation mode
on/off
General notes You can deactivate the flow of fresh air if
unpleasant odours are entering the vehicle
from outside. The air already inside the vehi-
cle will then be recirculated.
If you activate air-recirculation mode, the win-
dows can mist up more quickly, in particular
at low temperatures. Only use air-recircula-
tion mode briefly to prevent the windows
misting up.
The operation of air-recirculation mode is the same for all control panels.
Switching on/off X
Turn the key to position 2in the ignition
lock (Y page 157).
X To activate: press theebutton.
The indicator lamp in the ebutton lights
up.
THERMOTRONIC automatic climate con-
trol: air-recirculation mode is activated auto-
matically:
R at high outside temperatures
R at high levels of pollution
When air-recirculation mode is activated
automatically, the indicator lamp in the e
button is not lit. Outside air is added after
about 30 minutes. X
To deactivate: press theebutton.
The indicator lamp in the ebutton goes
out.
i Air-recirculation mode is deactivated
automatically:
R after approximately five minutes at out-
side temperatures below approximately
7 †
R after approximately five minutes if the
"Cooling with air dehumidification" func-
tion is deactivated
R after approximately 30 minutes at out-
side temperatures above approximately
7 † if the cooling with air dehumidifica-
tion function is activated Convenience opening or closing using
the air-recirculation button G
WARNING
When the convenience closing feature is oper- ating, parts of the body could become trapped
in the closing area of the side window and the
sliding sunroof. There is a risk of injury.
Observe the complete closing procedure
when the convenience closing feature is oper-
ating. When closing make sure that no parts of the body are in the closing area. G
WARNING
During convenience opening parts of the body could be drawn in or become trapped
between the side window and window frame.
There is a risk of injury. 146
Operating the climate control systemClimate control

Engine
Display messages
Possible causes/consequences and
M
MSolutions +
Top Top
up
upcoolant
coolant See
See
Owner's Manual
Owner's Manual The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Top up the coolant, observing the warning notes before doing so
(Y page 326).
If you have to top up the coolant frequently:
X Contact a qualified specialist workshop and have the engine
cooling system checked. ? The fan motor is faulty.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid putting the engine under heavy load as you do so, e.g.
driving in mountainous terrain and stop-start traffic. ?
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 is overheated can cause some fluids which 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 traf-
fic conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 184).
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 display.
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 †. Display messages
275On-board computer/Displays Z

Problem
Possible causes/consequences and
M
MSolutions ?
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 malfunc-
tioning.
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 Safeguard the vehicle against rolling away (Y page 184).
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, observing the
warning notes (Y page 326).
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 putting the engine under heavy load 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.
G WARNING
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.
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 traf-
fic conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 184).302
Warning and indicator lamps in the instrument clusterOn-board computer/Displays

Problem
Possible causes/consequences and
M
MSolutions 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, observing the
warning notes (Y page 326).
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 below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid putting the engine under heavy load as you do so, e.g.
driving in mountainous terrain and stop-start traffic. Driving systems
Problem
Possible causes/consequences and
M MSolutions ·
The red distance warn-
ing 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. ·
The red distance warn-
ing 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.
For further information on the distance warning function of COL-
LISION PREVENTION ASSIST PLUS, see (Y page 70).Warning and indicator lamps in the instrument cluster
303On-board computer/Displays Z

Damage to the engine or exhaust system is
caused by the following:
R using engine oils and oil filters that have
not been specifically approved for the
service system
R changing the engine oil and oil filter after
missing the change interval required by
the service system
R using 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 dip-
stick (Y page 324).
For further information on engine oil, see
(Y page 400). 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 cool-
ant temperature is over 40 † can lead to
damage to the engine or engine cooling
system. Example
X Park the vehicle on a level surface.
Only check the coolant level if the vehicle is
on a level surface and the engine has
cooled down.
X Turn the key to position 2in the ignition
lock (Y page 157).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
40 †.
X Turn the key to position 0in the ignition
lock (Y page 157). 326
Engine compartmentMaintenance and care

Engine oil viscosity
Viscosity describes the flow characteristics
of a fluid. If an engine oil has a high viscosity
rating, it flows slowly; the lower the viscosity,
the faster it flows.
Engine oil selection is based on the respective outside temperatures and in accordance with
the SAE classification (viscosity). The table
shows you which SAE classifications are to be
used. The low-temperature properties of
engine oils can be significantly impaired dur-
ing operation due to, for example, ageing or
soot and fuel accretion. It is therefore
strongly recommended to observe regular oil changes using an approved engine oil with the
appropriate SAE classification. Brake fluid
G
WARNING
The brake fluid continuously absorbs mois-
ture from the air. This results in the boiling
point of the brake fluid lowering. If the boiling
point of the brake fluid is too low, vapour
pockets may form when the brakes are sub-
jected to a heavy load. This would impair brak- ing efficiency. There is a risk of an accident.
Have the brake fluid renewed at the prescri-
bed intervals.
When handling brake fluid, observe the
important safety notes on service products
(Y page 396).
The brake fluid change intervals can be found in the Service Booklet. Only use brake fluid approved by Mercedes-
Benz according to MB-Freigabe or MB-
Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist work-
shop or on the Internet at
http://bevo.mercedes-benz.com.
i Have the brake fluid regularly replaced at
a qualified specialist workshop and the
replacement 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 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.
i Have the coolant regularly replaced at a
qualified specialist workshop and the
replacement confirmed in the Service
Booklet. 402
Service products and capacitiesTechnical data