2020 MERCEDES-BENZ METRIS check engine light

Engine
Warning/
indicator
lamp
N Signal type
Possible causes/consequences and
M Solutions;
N The yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction in the following vehicle systems:
R in the engine management
R in the transmission management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with a gasoline engine)
R in the fuel system
The emission limit values may be exceeded and the engine may be running in
emergency mode.
X Have the vehicle checked as soon as possible at a qualified specialist work-
shop. 6
N The yellow reserve fuel warning lamp is on while the engine is running.
The fuel level has dropped to the reserve range.
X Refuel at the nearest gas station. ?
N The red coolant warning lamp comes on while the engine is running.
On vehicles without steering wheel buttons, the coolant temperature gauge is at
the start of the bar display
(Y page 178).
On vehicles with steering wheel buttons, the coolant temperature gauge is at
the start of the scale in the instrument cluster ( Y page 40).
The temperature sensor for the coolant temperature gauge is faulty.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine. Do not continue driving under any circumstances.
X Secure the vehicle to prevent it from rolling away (Y page
138).
X Consult a qualified specialist workshop. Indicator and warning lamps in the instrument cluster
233
On-board computer and displays Z

Warning/
indicator
lamp
N Signal type
Possible causes/consequences and
M SolutionsX
Secure the vehicle to prevent it from rolling away ( Y page 138).
X Exit the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and add coolant, observing the warning notes
(Y page
253).
X If you have to add coolant more frequently, have the engine cooling system
checked.
X Make sure that the air supply to the radiator is not obstructed, by frozen
slush for example.
X Check the coolant temperature:
R using the display in the on-board computer on vehicles without steering
wheel buttons ( Y page

178)
R using the analog display in the instrument cluster on vehicles with steering
wheel buttons ( Y page 40)
X If the coolant temperature is below the maximum value specified below, you
can continue driving to the nearest qualified specialist workshop.
Avoid heavy loads on the engine, e.g. driving in mountainous terrain, and
stop-start traffic.
Under normal driving conditions and at the correct coolant level, the coolant
temperature display may rise to the letter H or to the red mark.Driving systems
Warning/
indicator
lamp
N Signal type
Possible causes/consequences and
M Solutions·
N The red distance warning 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. ·
N The red distance warning lamp lights up while the vehicle is in motion. An
additional warning tone 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 particular attention to the traffic situation. You may have to brake or take
evasive action.
Further information about the distance warning function can be found under
"COLLISION PREVENTION ASSIST"
(Y page 149). Indicator and warning lamps in the instrument cluster
235
On-board computer and displays Z

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

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

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

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

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. 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.
! Vehicles with a gasoline engine:
avoid
repeated and lengthy starting attempts. Oth-
erwise, the catalytic converter could be
damaged by non-combusted fuel.
If the indicator and warning lamps in the
instrument cluster do not light up at low tem-
peratures, the discharged battery may have
frozen. In this case you may neither charge the
battery nor jump-start the vehicle. The service
life of a thawed battery may be shorter. Start-
up behavior may deteriorate, in particular at
low temperatures. Have the thawed battery
checked at a qualified specialist workshop.
Do not use a rapid charging device to start the
vehicle. If your vehicle's battery is discharged,
the engine can be jump-started from another
vehicle or from a donor battery using jumper
cables. For this purpose, the vehicle has a
jump-starting connection point in the engine
compartment.
When jump-starting, observe the following
points:
R The battery is not accessible in all vehicles.
If the other vehicle's battery is not accessi-
ble, jump-start the vehicle using a donor
battery or a jump-starting device.
R You may only jump-start the vehicle when
the engine and exhaust system are cold.
R Do not start the engine if the battery is fro-
zen. Let the battery thaw first. R
Jump-starting may only be performed from
batteries with a nominal voltage of 12 V.
R Only use jumper cables that have a suffi-
cient cross-section and insulated terminal
clamps.
R If the battery is fully discharged, attach the
battery of another vehicle for a few minutes
before attempting to start. This charges the
empty battery a little.
R Make sure that the two vehicles do not
touch.
Make sure that:
R The jumper cables are not damaged.
R Bare parts of the terminal clamps do not
come into contact with other metal parts
while the jumper cables are connected to
the battery.
R The jumper cables cannot come into contact
with parts such as the V-belt pulley or the
fan. These parts move when the engine is
started and while it is running.
Jumper cables and further information regard-
ing jump starting can be obtained at any quali-
fied specialist workshop. Before connecting the jumper cables
X Apply the parking brake.
X Shift the transmission to position j.
X Switch off all electrical consumers, e.g.
audio equipment, blower.
X Turn the key to position u in the ignition
lock and remove it .
X Open the hood (Y page 251). Connecting the jumper cable Jump-starting
273
Breakdown assistance Z

X
Push contact protection cover : of the
jump-starting connection point backwards
against the spring force as far as it will go.
The jump-starting connection point is visi-
ble. Terminal connecting plan
X Remove the cover from positive terminal =
of the donor vehicle's battery.
X Connect the positive terminal clamp of the
jumper cable to positive terminal = of the
donor vehicle's battery, and then to positive
terminal A of the jump-starting connection
point.
X Run the donor vehicle's engine at idling
speed.
X Connect the negative terminal clamp of the
jumper cable to negative terminal ; of the
donor vehicle's battery, and then to ground
contact ? of your own vehicle.
X Insert the key into the ignition lock and start
the engine.
You can now switch electrical consumers
back on except the lighting system.
X Before disconnecting the jumper cables, let
the engine run for several minutes.
X Disconnect the negative terminal of the
jumper cable from ground contact ? and
then from negative terminal ; of the donor
vehicle's battery.
X Disconnect the positive terminal clamp of
the jumper cable from positive terminal A
on the jump-starting connection point, and
then from positive terminal = of the donor
vehicle's battery.
Contact protection cover : is automatically
returned forwards to its original position by
the spring force and the jump-starting con-
nection point is closed. X
Position the cover on positive terminal = of
the donor vehicle's battery.
You can now switch on the lighting system.
X Have the battery checked at a qualified spe-
cialist workshop. Tow-starting and towing away
Important safety notes
G
WARNING
Functions relevant to safety are restricted or
no longer available if:
R the engine is not running.
R the brake system or the power steering is
malfunctioning.
R there is a malfunction in the voltage sup-
ply or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely. G
WARNING
You can no longer steer the vehicle if the
steering wheel lock has been engaged.
There is a risk of an accident.
Always switch off the ignition when towing
the vehicle with a tow cable or a tow bar. G
WARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissi-
ble gross weight of your vehicle, the:
R the towing eye could detach itself
R the vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehi-
cle, its weight should not be greater than
the permissible gross weight of your vehicle.
Information on the gross vehicle weight can be
found on the vehicle identification plate
(Y page
304).274
Tow-starting and towing away
Breakdown assistance