maintenance MERCEDES-BENZ METRIS 2020 MY20 Operator’s Manual

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

Have the brake fluid renewed every two years
at a qualified specialist workshop. Observe the
information regarding brake fluid in the "Ser-
vice products and capacities" section
(Y page
310).Check the brake fluid level regularly, e.g.
weekly or when refueling.
Checking the brake fluid level
X Stop your vehicle as far away from traffic as
possible on level ground.
X Switch off the engine.
X Secure the vehicle to prevent it from rolling
away.
X Open the hood (Y page
251).
X Check the brake fluid level.
The brake fluid level is adequate if the level
is between the MIN mark and MAX mark on
brake fluid reservoir :.
X Close the hood. Washer fluid
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. G
WARNING
Windshield washer concentrate is highly
flammable. If windshield washer concentrate
gets onto hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury.
Make sure that windshield washer concen-
trate is not spilled in the vicinity of the filler
neck.
! Only use washer fluid which is suitable for
lamp lenses, e.g. MB SummerFit or MB Win-
terFit. Unsuitable washer fluid may damage
the lamp lenses of the headlamps. Example: washer fluid reservoir
Add windshield washer concentrate to the
washer fluid all year round. Observe the infor-
mation regarding washer fluid under "Service
Products and Capacities"

(Y page 312).
Adding washer fluid
X Mix the washer fluid to the appropriate mix-
ing ratio in a container beforehand.
X Open the hood ( Y page
251).
X Pull cap : on the washer fluid reservoir
upwards at the tab.
X Add the premixed washer fluid.
X Press cap : onto the filler neck until it
engages audibly.
X Close the hood.256
Engine compartment
Maintenance and care

Maintenance
General notes
H
Environmental note
Observe measures to protect the environ-
ment when working on the vehicle. You
must observe the legal requirements when
disposing of service products, e.g. engine
oil. This also includes all components, e.g.
filters, which have come into contact with
service products. Any qualified specialist
workshop can provide information about
this.
Dispose of empty containers, cleaning
cloths and care products in an environmen-
tally responsible manner. Comply with the
instructions for use of the care products.
Do not run the engine for longer than neces-
sary when the vehicle is stationary.
Before carrying out maintenance measures
and repairs, you must read the following docu-
ments relating to maintenance measures and
repairs:
R relevant sections of the technical documen-
tation such as the Operator's Manual and
workshop information
R legal stipulations such as work safety regu-
lations and accident prevention regulations
While working under the vehicle, you must
secure the vehicle on jack stands with suffi-
cient load capacity.
Never use a vehicle jack instead of stands. The
jack is designed only to raise the vehicle for a
short time when changing a wheel. It is not
suited for performing maintenance work under
the vehicle.
Please also refer to the notes about qualified
specialist workshops
(Y page 32).
The scope and regularity of the inspection and
maintenance work primarily depend on the
often diverse operating conditions. Specialist
knowledge beyond the scope of this Opera-
tor's Manual is required when carrying out
testing and maintenance work. This work
should only be carried out by trained staff.
The vehicle Maintenance Booklet describes
the scope and frequency of maintenance work
and contains additional notes on the Limited
Warranty. You will find information about ser- vice products approved by Mercedes-Benz and
capacities under "Service products and capaci-
ties"

(Y page 305)
Maintenance services must be carried out in
accordance with the provisions and recom-
mendations in the Maintenance Booklet. Not
doing so could void the warranty claim and
lead to refusal of goodwill gestures after the
manufacturer has submitted a damage report.
Observe the information under "Mercedes-
Benz genuine parts" (Y page 34). Service interval display
General notes The service interval display informs you of the
next service due date. Information on the type
of service and service intervals can be found in
the Maintenance Booklet.
i The service interval display does not pro-
vide information about the engine oil level.
The service interval display should therefore
not be confused with the engine oil level dis-
play.
For example, the display shows one of the fol-
lowing service messages for a few seconds: R Service A in .. days
R Service A Due or Service A Due
R Serv. A Exceed. by .. Days
Then either the remaining time or distance
until the next service due date is displayed. If
the service due date has been exceeded, the
elapsed time or distance traveled after the
overdue service date is shown. The letter in
the display message indicates which service is
due. A stands for a minor service and B for a
major service.
A qualified specialist workshop, e.g. an author-
ized Mercedes-Benz Commercial Van Center,
will reset the service interval display after the
service work has been carried out. You can
also obtain further information on mainte-
nance work, for example. Maintenance
257
Maintenance and care Z

The prescribed service interval is based on
normal vehicle use. Service work will need to
be performed more frequently than prescribed
if the vehicle is operated under more arduous
conditions or with higher loads. Such arduous
conditions include:
R regular city driving with frequent intermedi-
ate stops
R driving predominantly short distances
R frequent operation in mountainous terrain or
on poor road surfaces
R leaving the engine idling for long periods on
a frequent basis
In these or similar operating conditions, have
the air filter, engine oil and oil filter, for exam-
ple, replaced more frequently. Under more
arduous operating conditions, the tires must
be checked more often. Further information
can be obtained at a qualified specialist work-
shop, e.g. an authorized Mercedes-Benz Com-
mercial Van Center.
Hiding service messages Vehicles without steering wheel buttons
X Press the 3 button on the instrument clus-
ter.
Vehicles with steering wheel buttons
X Press the a or % button on the steer-
ing wheel.
Calling up the service due date Vehicles without steering wheel buttons
The vehicle must be stationary. Use the but-
tons in the instrument cluster.
X Turn the key to position 2 in the ignition
lock.
X Press È to select the service display.
The display shows a possible service mes-
sage.
Vehicles with steering wheel buttons
Using the steering wheel buttons
X Turn the key to position 2 in the ignition
lock.
X Press = or ; to select the Service
menu.
X Press 9 or : to select the ASSYST
PLUS submenu and press a to confirm.
The display shows the service due date. Battery
Important safety notes
Work on the battery, e.g. removing or instal-
ling, requires specialist knowledge and the use
of special tools. Therefore, always have work
on the battery carried out at a qualified spe-
cialist workshop. G
WARNING
Work carried out incorrectly on the battery
can lead, for example, to a short circuit and
thus damage the vehicle electronics. This
can lead to function restrictions applying to
safety-relevant systems, e.g. the lighting
system, the ABS (anti-lock braking system)
or the ESP ®
(Electronic Stability Program).
The operating safety of your vehicle may be
restricted.
You could lose control of the vehicle, for
example:
R when braking
R in the event of abrupt steering maneuvers
and/or when the vehicle's speed is not
adapted to the road conditions
There is a risk of an accident.
In the event of a short circuit or a similar
incident, contact a qualified specialist work-
shop immediately. Do not drive any further.
You should have all work involving the bat-
tery carried out at a qualified specialist
workshop.
Further information can be found under "ABS"
(Y page
67) and under "ESP ®
" (Y page 68). G
WARNING
Electrostatic build-up can lead to the crea-
tion of sparks, which could ignite the highly
explosive gases of a battery. There is a risk
of an explosion.
Before handling the battery, touch the vehi-
cle body to remove any existing electrostatic
build-up.
The flammable gas mix is produced when the
battery is charged or when the vehicle is jump-
started. 258
Battery
Maintenance and care

Always make sure that neither you nor the bat-
tery are electro statically charged.
An electrostatic charge can build up in the fol-
lowing situations:
R wearing synthetic clothing
R friction between clothing and the seat
R dragging or pushing the battery across car-
pet flooring or any other synthetic materials
R by rubbing the battery with a cloth or towels
Comply with the following safety precautions
and take protective measures when handling
batteries. Risk of explosion. Explosive oxyhy-
drogen is produced when batteries
are being charged. Only charge
batteries in well-ventilated areas.
Fire, open flames and smoking are
therefore prohibited when working
on the battery. Avoid creating
sparks.
Battery acid is caustic. Avoid con-
tact with the skin, eyes or clothing.
Wear acid-proof protective gloves.
If skin or clothes are splashed with
acid, neutralize the splashes imme-
diately with soapy water or an acid
neutralizer, and then clean the
affected areas with water. Consult
a doctor if necessary.
Wear eye protection. When mixing
water and acid, the liquid can
splash into your eyes. Rinse acid
splashes to the eyes immediately
with clean water and contact a
doctor immediately.
Keep children at a safe distance.
Children are not able to assess the
dangers posed by batteries and
acid.
When handling batteries, observe
the safety precautions and special
protective measures contained in
this Operator's Manual.
H
Environmental note Batteries contain pollutants.
It is illegal to dispose of
them with the household
rubbish. They must be col-
lected separately and dis-
posed of in an environmen- tally responsible recycling
system. Dispose of batteries in an
environmentally responsible
manner. Take discharged
batteries to a qualified spe-
cialist workshop or to a col-
lection point for used bat-
teries.
Observe the following notes: R have the batteries recharged more fre-
quently in the following situations:
- if you predominantly drive short distan-
ces.
- if you predominantly drive at low outside
temperatures.
- if you leave the vehicle parked for a
lengthy period.
In order for the batteries to achieve their
maximum possible service life, they must
always be sufficiently charged.
R Consult an authorized Mercedes-Benz Com-
mercial Van Center if you wish to leave your
vehicle parked for a long period of time.
R When you park the vehicle, remove the key
if you do not require any electrical consum-
ers. The vehicle will then use very little
energy, thus conserving battery power.
R If your vehicle requires jump-starting, or if
you wish to provide jump-starting assistance
to another vehicle, only use the jump-start-
ing connection point in the engine compart-
ment
(Y page 272).
R Have the battery removed at a qualified spe-
cialist workshop. Installation locations
Your vehicle may be equipped with the follow-
ing three batteries, depending on the equip-
ment level:
R Starter battery in the seat base of the right-
hand front seat
R Auxiliary battery in the seat base of the
right-hand front seat
R Additional battery in the seat base of the
left-hand front seat Battery
259
Maintenance and care Z

Disconnecting and removing
G
WARNING
During the charging process, a battery pro-
duces hydrogen gas. If a short circuit occurs
or sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a
connected battery does not come into
contact with vehicle parts.
R Never place metal objects or tools on a
battery.
R It is important that you observe the
described order of the battery terminals
when connecting and disconnecting a bat-
tery.
R When jump-starting, make sure that the
battery poles with identical polarity are
connected.
R It is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables.
R Never connect or disconnect the battery
terminals while the engine is running. G
WARNING
Battery acid is caustic. There is a risk of
injury.
Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash away battery acid immedi-
ately with plenty of clean water and seek
medical attention.
! You should have all work involving the bat-
tery carried out at a qualified specialist
workshop.
If, in exceptional circumstances, you need
to disconnect the battery yourself, please
make sure that:
R Secure the vehicle to prevent it from roll-
ing away.
R You have switched off the engine and
removed the key. Make sure the ignition
is switched off. Check to see that there
are no indicator lamps lighting in the instrument cluster. Electronic compo-
nents such as the alternator may other-
wise be damaged.
R After the battery has been disconnected,
the parking brake is automatically
engaged. You can then no longer move
the vehicle.
R For vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. You can
then no longer move the vehicle.
R You have first removed the negative ter-
minal and then the positive terminal.
Never mix up the terminal clamp discon-
nection/connection order and never mix
up the terminal clamps. The vehicle's
electronics may otherwise be damaged.
The battery and the cover of the positive ter-
minal clamp must be installed securely dur-
ing operation. Seat base (example: right-hand front seat)
The following description on disconnecting
and removing the battery is based upon the
example of the starter battery in the seat base
of the driver's seat. The additional battery is
disconnected and removed in the same way as
the starter battery. The auxiliary battery is
located in the seat base of the left-hand front
seat.
X Switch off all electrical consumers.
X Switch off the engine and remove the key
from the ignition lock.
X Open the front door on the right-hand side.
i To disconnect or remove the additional
battery, open the left-hand front door. The
auxiliary battery is located in the seat base
of the left-hand front seat. 260
BatteryMaintenance and care

X
Press both latching springs : down and
remove cover ; upwards from the seat
base.
X Remove cover ; by pulling upwards at an
angle from the seat base. Open seat base (example: right-hand front seat)
X Remove screws A from holder B.
X Remove holder B.
X Remove breather hose ? from the top of
the battery.
X Pull the battery out of the seat base until
the negative clamp can be released and
removed.
X Disconnect the negative clamp from nega-
tive terminal =.
X Remove the negative clamp in such a way
that the battery cable terminal no longer
touches negative terminal =. Example: starter battery
X Remove the battery from the seat base and
place it on the door sill panel as shown. If
necessary, hold the battery by handles E.
X Remove the positive clamp cover from posi-
tive terminal C.
X Loosen positive clamp D on positive termi-
nal C. X
Remove positive clamp D in such a way
that the battery cable terminal no longer
touches positive terminal C.
X Lift the battery from the door sill panel by
handles E. Reconnecting and installing
G
WARNING
During the charging process, a battery pro-
duces hydrogen gas. If a short circuit occurs
or sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a
connected battery does not come into
contact with vehicle parts.
R Never place metal objects or tools on a
battery.
R It is important that you observe the
described order of the battery terminals
when connecting and disconnecting a bat-
tery.
R When jump-starting, make sure that the
battery poles with identical polarity are
connected.
R It is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables.
R Never connect or disconnect the battery
terminals while the engine is running.
! Always connect the battery in the order
described below. Never mix up the terminal
clamp disconnection/connection order and
never mix up the terminal clamps. You may
otherwise damage the vehicle electronics.
Always observe the prescribed positive ter-
minal installation position when doing so.
Otherwise, the positive clamp may come
into contact with vehicle parts. In this case
there is a risk that the vehicle may short-cir-
cuit and catch fire.
The following description on connecting and
installing the battery is based upon the exam-
ple of the starter battery in the seat base of
the right-hand front seat. The additional bat-
tery is connected and installed in the same
way as the starter battery. The auxiliary bat- Battery
261Maintenance and care Z

tery is located in the seat base of the left-hand
front seat.
Example: starter battery
X Place the battery on the door sill panel as
shown and secure with handles = if neces-
sary.
X Connect positive clamp ; to positive termi-
nal :. Always observe the positive terminal
installation position shown when doing so.
The positive lead must be routed parallel to
the side of the battery housing in the con-
nection area.
X Place the positive clamp cover on positive
terminal :.
X Fold both handles = down onto the battery.
X Push the battery into the seat base until the
negative terminal can be connected.
X Connect the negative clamp to negative ter-
minal ?.
X Push the battery into the seat base as far as
it will go. Open seat base with installed battery (example:
right-hand front seat) X
Push vent hose A onto the battery connec-
tion next to the negative pole ? at the top.
X Guide holder C over the lower side of the
battery housing and the threads for screws
B.
X Screw on holder C with screws B.
The battery is secured to prevent slipping. Seat base (example: right-hand front seat)
X Insert cover E down in front of the battery
compartment into the seat base and close
it.
Latching springs D of cover E should
engage audibly.
Carry out the following work after connecting
the battery:
X Reset the side window (Y page 86).
X Reset the electric sliding doors ( Y page
80). Charging
G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery,
gases can escape from the battery. There is
a risk of an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
If the indicator/warning lamps do not light up
in the instrument cluster when temperatures
are low, it is probably because the discharged
battery has frozen. Should this be the case, do
not jump-start the vehicle or charge the bat-
tery. The service life of a thawed battery may
be shorter. Start-up behavior may deteriorate,
in particular at low temperatures. Have the 262
Battery
Maintenance and care

thawed battery checked at a qualified special-
ist workshop.
G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is
a risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is suffi-
cient ventilation while charging and jump-
starting. Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of
injury.
Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash away battery acid immedi-
ately with plenty of clean water and seek
medical attention.
! Charge the installed battery only with a
charger approved for Mercedes-Benz. This
device allows the battery to be charged
while it is installed in the vehicle. The vehi-
cle's electronics system may otherwise be
damaged.
! Only charge the battery using the jump-
starting connection point.
A battery charger unit specially adapted for
Mercedes-Benz vehicles and tested and
approved by Mercedes-Benz is available as an
accessory. Only this device permits the charg-
ing of the battery in its installed position. Con-
tact an authorized Mercedes-Benz Commercial
Van Center for information and availability.
Read the operating instructions for your
charger before charging the battery.
Recharge the battery more frequently if you
use the vehicle mainly for short trips and/or
drive at low outside temperatures.
Only charge the installed battery with a battery
charger that has been tested and approved by
Mercedes-Benz, using the jump-start connec-
tion point in the engine compartment.
X Connect the battery charger to the positive
terminal and ground terminal in the same
order as when connecting the donor battery in the jump-starting procedure
(Y page
272).
i If a battery is not installed and not in ser-
vice, you should charge it every three
months. This will counter self-discharging
and prevent battery damage. Care
12 V battery !
Dirty battery clamps and battery surfaces
cause leak currents which lead to the bat-
teries discharging.
! Do not use cleaning agents containing
fuel. Cleaning agents containing fuel cor-
rode the battery housing.
! If dirt gets into the battery cell, battery
self-discharge will increase and the battery
may be damaged.
The following points on battery care must be
observed:
X Regularly check the battery terminals and
the fastening of the negative cable to the
chassis to ensure that they are firmly
seated.
X Always keep the battery terminals and bat-
tery surfaces clean and dry.
X Lightly grease the undersides of the battery
terminals with acid-resistant grease.
X Only clean the battery casing with a com-
mercially available cleaning product. Care
Notes on care
G
WARNING
If you use openings in the bodywork or
detachable parts as steps, you could:
R slip and/or fall
R damage the vehicle and cause yourself to
fall.
There is a risk of injury.
Always use secure climbing aids, e.g. a suit-
able ladder. Care
263
Maintenance and care Z

!
Do not use the lower sliding door guide
(carriage) as a step. Otherwise, you could
damage the paneling and/or the sliding
door mechanism.
! When cleaning your car, do not use:
R dry, coarse or hard cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvents
Do not scrub.
Do not touch the surfaces and films with
hard objects, e.g. rings or ice scrapers. Oth-
erwise, you may scratch or damage the sur-
faces and films.
! Do not park your vehicle for a long period
of time directly after cleaning, particularly
after cleaning the wheel rim with wheel
cleaner. Wheel cleaner can lead to the
increased corrosion of the brake discs and
pads. Therefore, drive for a few minutes
after cleaning. By heating up the brakes, the
brake discs and pads dry. The vehicle can
then be parked for a long period of time. H
Environmental note
Only clean your vehicle at specially designed
wash bays. Dispose of empty containers and
used cleaning products in an environmen-
tally responsible manner. H
Environmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible
manner.
Regular care of your vehicle is a condition for
retaining the quality in the long term.
Use care products and cleaning agents recom-
mended and approved by Mercedes-Benz. Washing the vehicle and cleaning
the paintwork
Automatic car wash G
WARNING
Braking efficiency is reduced after washing
the vehicle. There is a risk of an accident. After the vehicle has been washed, brake
carefully while paying attention to the traffic
conditions until full braking power is
restored.
! Make sure that the automatic car wash is
suitable for the size of the vehicle.
Before washing the vehicle in an automatic
car wash, fold in the exterior mirrors and
remove any additional antennas. Otherwise,
the exterior mirror, antenna or the vehicle
itself could be damaged.
Make sure that the exterior mirrors are fully
folded out again and that any additional
antennas are re-installed when you leave the
automatic car wash.
! Make sure that:
R the side windows and roof are completely
closed
R the climate control blower is switched off
R the windshield wiper switch is in position
0
The vehicle may otherwise be damaged.
You can wash the vehicle in an automatic car
wash from the very start.
Wash off excess dirt before cleaning the vehi-
cle in an automatic car wash.
After putting the vehicle through an automatic
car wash, wipe off wax from:
R the windshield
R the windshield wiper blades
This will prevent smears and reduce wiping
noises caused by residue on the windshield.
R on vehicles with rear-end doors, from the
rear view camera lens in the top of the
license plate molding
(Y page 267)
Washing by hand In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements of the country
you are currently in when washing by hand.
X Do not use hot water and do not wash the
vehicle in direct sunlight.
X Use a soft car sponge.
X Use a mild cleaning agent, e.g. a Mercedes-
Benz approved car shampoo.264
Care
Maintenance and care