Where possible, let the engine cool down and
touch only the components described in the
following.
G WARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There
is a risk of injury.
If you need to do any work inside the engine
compartment: R
switch off the ignition R
never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area R
remove jewelry and watches R
keep items of clothing and hair, for exam-
ple, away from moving parts
G WARNING
The cooling system is pressurized, particularly
when the motor 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. Slowly
open the cap to relieve pressure.
G WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department. Checking coolant level
Checking the coolant level (example) X
Park the vehicle on a level surface.
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down. X
Turn the SmartKey to position H in the igni-
tion lock ( Y
page 132).
or X
Press the Start/Stop button twice on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function ( Y
page 133). X
Check the coolant temperature display in the
instrument cluster ( Y
page 36).
The coolant temperature must be below
158 ‡ (70 †). X
Turn the SmartKey to position Z in the igni-
tion lock ( Y
page 132).
or X
Press the Start/Stop button once on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function ( Y
page 133). X
Slowly turn cap C half a turn counter-clock-
wise and allow excess pressure to escape. X
Turn cap C further counter-clockwise and
remove it.
If the coolant is at the level of marker bar
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 Maintenance Booklet.
Comply with the important safety notes for ser-
vice products when handling coolant
( Y
page 364).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the fol-
lowing tasks: R
Anti-corrosion protection R
Antifreeze protection R
Raising the boiling point
If the coolant has antifreeze protection down to
-35 ‡ (-37 †), the boiling point of the coolant
during operation is approximately 266 ‡
(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 -35 ‡ (-37 †). R
not exceed 55% (antifreeze protection down
to -49 ‡[ -45 †]) . Otherwise , hea t will no t be
dissipated as effectively.
Mercedes-Ben z recommends an antifreeze/
corrosion inhibitor concentrat e in accordance
wit h MB Specification s fo r Servic e Products
310.1.
i Whe n th e vehicle is first delivered, it is filled
wit h a coolan t mixture that ensures adequat e
antifreez e an d anti-corrosio n protection .
i The coolan t is checke d wit h ever y mainte-
nanc e interval at a qualifie d specialis t work-
shop.
Filling capacities
Model Capacity
GLC 300 d 4MATIC
10.6 US qt (10.0 l)
Mercedes-AMG
GLC 43 4MATIC 12.2 US qt (11.5 l)
Al l ot her models
9.5 US qt (9.0 l) Windshield washer system
Important safety notes
G WARNING
Windshield washer concentrate could ignite if
it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield 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 dam-
age the plastic lenses of the headlamps.
! Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The
spray nozzles may otherwise become
blocked.
Do not use distilled or de-ionized 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 364).
At temperatures above freezing: X
Fill the washer fluid reservoir with a mixture of
water and windshield washer fluid, e.g. MB
SummerFit.
Add 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.
For the correct mixing ratio refer to the infor-
mation on the antifreeze reservoir.
i Add windshield washer fluid, e.g. MB Sum-
merFit or MB WinterFit, to the washer fluid all
year round.
Climate control system refrigerant
Important safety notes
The climate control system of your vehicle is fil-
led with refrigerant R ‑ 134a.
The instruction label regarding the refrigerant
type used can be found on the radiator cross
member.Service products and filling capacities 369
Technical data Z