2020 MERCEDES-BENZ METRIS coolant reservoir

Useful information
This Operator's Manual describes all models
as well as standard and optional equipment of
your vehicle that were available at the time of
going to print. Country-specific variations are
possible. Note that your vehicle may not be
equipped with all of the described functions.
This also applies to systems and functions rel-
evant to safety.
Read the information on qualified specialist
workshops (Y page
32).Engine compartment
Hood
Important safety notes G
WARNING
If the hood is unlatched, it may open up
when the vehicle is in motion and block your
view. There is a risk of an accident.
Never unlatch the hood while driving. Before
every trip, ensure that the hood is locked. 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. 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 ignition system operates with a high
voltage. If you touch the live components,
you could receive an electric shock. There is
an increased risk of injury.
Never touch components of the ignition sys-
tem if:
R the engine is running or being started
R the key is in radio position or drive posi-
tion in the ignition lock
The live components of the ignition system
are, for example:
R ignition coils
R spark plug connectors
R diagnostic sockets G
WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very
hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down
and touch only the components described in
the following.
If you have to carry out work in the engine
compartment, only touch the following compo-
nents:
R hood
R oil dipstick
R engine oil filler neck cap
R washer fluid reservoir cap
R coolant expansion tank cap250
Engine compartment
Maintenance and care

X
Hold support strut ? and lift the hood
slightly.
X Guide support strut ? towards retainer =
and apply slight pressure to make it engage.
X Lower the hood and allow it to fall with
momentum from a height of approximately
1 ft (30 cm
).
The hood locks audibly.
X Check that the hood is correctly locked.
If the hood can be raised slightly, it is not
properly engaged. If the hood is not cor-
rectly engaged, open the hood again. Let
the hood fall with a little more momentum. Overview of the engine compart-
ment
Engine compartment (example)
:
Engine oil filler neck cap (Y page
252)
; Brake fluid reservoir cap (Y page
255)
= Coolant expansion tank cap ( Y page
253)
? Washer fluid reservoir cap (Y page
256)
Regularly check the fluid level and the assem-
bly for leaks. If you detect fluid loss, e.g. oil
stains on the vehicle parking space, consult a
qualified specialist workshop immediately. Engine oil
General notes !
Engine oil gets dirty in the course of opera-
tion and its quality and volume are gradually
diminished. Regularly check the oil level,
and top up or have it replaced as needed.
Observe the information on approved engine
oils and oil consumption under "Service prod-
ucts and capacities" ( Y page

308).You can check the oil level in the engine:
R with the oil dipstick
Checking the oil level using the oil dip-
stick 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. G
WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very
hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down
and touch only the components described in
the following. Oil dipstick and engine oil filler neck
Only check the oil level when the engine is at
normal operating temperature. X Stop your vehicle as far away from traffic as
possible on level ground.
X Secure the vehicle to prevent it from rolling
away.
X Switch off the engine.
X Wait for five minutes.252
Engine compartment
Maintenance and care

X
Turn cap : further and remove it from cool-
ant expansion tank ;.
X Check the coolant level.
If the coolant is up to marker bar =
in the
filler neck when cold, there is a sufficient
amount of coolant in coolant expansion
tank ;.
If the coolant is approximately 0.59 in
(1.5 cm) above marker bar = in the filler
neck when warm, there is a sufficient
amount of coolant in coolant expansion
tank ;.
Adding coolant X If the coolant drops under marker bar = in
the filler neck, add coolant.
Observe the information on the correct cool-
ant mixture ratio and the required water
quality under "Service products and capaci-
ties" ( Y page

310). To prevent damage to
the engine cooling system, use only
approved corrosion inhibitor/antifreeze that
complies with the Mercedes-Benz Specifica-
tions for Service Products.
X Replace cap : and tighten in a clockwise
direction.
X Start the engine.
X Set the temperature in the vehicle interior to
the maximum output on the air-conditioning
system control panel.
X After approximately five minutes, switch off
the engine again and allow it to cool down.
X Check the coolant level again and add cool-
ant if necessary.
X Close the hood. Brake fluid
G
WARNING
Service products may be poisonous and haz-
ardous to health. There is a risk of injury.
Comply with instructions on the use, storage
and disposal of service products on the
labels of the respective original containers.
Always store service products sealed in their
original containers. Always keep service
products out of the reach of children. 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. G
WARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very
hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down
and touch only the components described in
the following.
Brake fluid is hazardous to health. Also
observe the safety notes under "Service prod-
ucts and capacities"
(Y page 305). G
WARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid. If the boiling point of the
brake fluid is too low, vapor pockets may
form in the brake system when the brakes
are applied hard. This would impair braking
efficiency. There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals.
! If the brake fluid level in the brake fluid
reservoir has fallen to the MIN mark or
below, check the brake system immediately
for leaks. Also check the thickness of the
brake linings. Visit a qualified specialist
workshop immediately.
Do not add brake fluid. This does not cor-
rect the malfunction.
! Brake fluid corrodes paint, plastic and rub-
ber. If paint, plastic or rubber has come into
contact with brake fluid, rinse with water
immediately. Engine compartment
255
Maintenance and care Z