coolant temperature MERCEDES-BENZ METRIS 2020 MY20 Operator’s Manual

120 km/h! (only for certain countries)
maximum permissible speed exceeded
= Display panel for display messages, menus
and menu bar
? Transmission position (Y page 132)
A Fuel level
Fuel filler flap location indicator t: the
fuel filler cap is on the left-hand side
B è Rear window wiper
(Y page 110)
Display panel = shows the selected menu or
submenu and display messages. Menu overview
The Settings menu is only displayed when
the vehicle is stationary. You can think of the
order of the menus and functions as a circle.
Press È on the instrument cluster to scroll
through the menus.
If you scroll forward in the Settings menu
using 3, the setting from the previous sub-
menu or function is adopted.
If you press È in a submenu, the submenu or
function is exited without adopting the setting.
The display then shows the start screen of the
Settings menu.
Operation information can be found under
"Operating the on-board computer"
(Y page

176).
Depending on the vehicle equipment, you can
call up the following menus, displays or func-
tions:
R trip odometer and odometer display
(Y page 177)
R trip computer display (Y page 177)
R current range display (Y page 178)
R current fuel consumption display
(Y page 178)
R digital speedometer ( Y page 178)
R coolant temperature gage (Y page 178)
R display messages in the message memory
(Y page 195)
The following menus, displays and functions
are only displayed when the vehicle is station-
ary:
R next service due date display ( Y page 258)
R tire pressure monitor restart (Y page 285)
R Settings menu for setting or activating/
deactivating driving and driver assistance systems as well as display options
(Y page

179) Distance menu
Odometer
If the display shows the speed in the header,
the display beside trip odometer : also
shows the outside temperature.
You can switch the permanent display in the
header

(Y page 180).
Use the buttons in the instrument cluster.
X To display: press and hold È until the dis-
play shows trip odometer : and odome-
ter ;.
X To reset: press and hold 3 until the trip
odometer is reset to 0.0.
You can set the unit of measurement for the
trip odometer in the Distance Unit: sub-
menu (Y page

180). Trip computer menu
Trip computer
:
Distance
; Length of journey
= Average fuel consumption
? Average speed On-board computer (vehicles without steering wheel buttons)
177
On-board computer and displays Z

Use the buttons in the instrument cluster.
X To display: press È to select the trip com-
puter display.
The values displayed relate to those meas-
ured since the trip computer was last reset.
X To reset values: press and hold 3 until all
values are reset.
The trip computer is automatically reset if the
value exceeds 9,999 hours or 99,999 miles.
You can set the unit of measurement for con-
sumption and distance in the Distance
Unit: submenu ( Y page 180).Range menu
Use the buttons in the instrument cluster.
X Press È to select the Range display.
The approximate range that can be covered
is calculated according to your current driv-
ing style and the amount of fuel in the tank.
If there is only a small amount of fuel left in
the fuel tank, the display shows a vehicle
being refueled Ï instead of the approxi-
mate range.
You can set the unit of measurement for dis-
tance in the Distance Unit: submenu
(Y page

180). Current fuel consumption menu
:
Recuperation display
; Range Use the buttons in the instrument cluster.
X Press È to select the fuel consumption bar
display.
Recuperation display : shows whether, and,
if so, how much kinetic energy is being trans-
formed into electric current whilst the vehicle
is coasting. The recuperated energy is then
stored in the starter battery. Recuperation dis-
play : is dependent on the engine installed
and is therefore not available in all vehicles.
You can set the unit of measurement for con-
sumption in the Distance Unit: submenu
(Y page

180). Digital speedometer menu
Use the buttons in the instrument cluster.
X Press È to select the speed display.
You can set the unit for the digital speedome-
ter in the Distance Unit: submenu
(Y page

180). Coolant temperature menu
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. 178
On-board computer (vehicles without steering wheel buttons)
On-board computer and displays

Engine
Display messages
Possible causes/consequences and
M Solutions# An additional warning tone sounds. The battery is not being
charged.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
! Do not drive any further. Otherwise the engine may overheat.
X Secure the vehicle to prevent it from rolling away ( Y page 138).
X Consult a qualified specialist workshop. ?
Stop Vehicle Turn
Eng. Off An additional warning tone sounds. The coolant is too hot.
G WARNING
Never drive with an overheated engine. Driving when the engine is
overheated can cause 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 hood.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away ( Y page
138).
X Wait until the engine has cooled down.
X Make sure that the air supply to the radiator is not obstructed, by
frozen slush for example.
X Do not start the engine again until the display message goes out
and the coolant temperature is below the maximum value speci-
fied. The engine could otherwise be damaged.
X Pay attention to the coolant temperature gauge (Y page
178).
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal driving conditions and at the correct coolant level, the
coolant temperature gauge may rise to the letter H.204
Display messages (vehicles without steering wheel buttons)
On-board computer and displays

Display messages
Possible causes/consequences and
M Solutions? The fan motor is faulty.
X Check the coolant temperature (Y page 178).
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 ter-
rain, and stop-and-go traffic.
Under normal driving conditions and at the correct coolant level, the
coolant temperature gauge may rise to the letter H.Check Coolant Level
+ The coolant level is too low.
! Avoid longer journeys when there is insufficient coolant in the
engine cooling system. You could otherwise damage the engine.
X Add coolant, making sure to observe the warning notes
(Y page
253).
X Have the engine cooling system checked at a qualified specialist
workshop if the coolant needs to be refilled more often than
usual. 4
Check Engine Oil
Level An additional warning tone sounds. The engine oil level has dropped
to the minimum level.
X Check the oil level at the latest when next refueling
(Y page

252).
X If necessary, add engine oil ( Y page
253).
X Have the engine checked at a qualified specialist workshop if you
need to add engine oil more often than usual.
! Avoid longer journeys when there is insufficient engine oil. You
could otherwise damage the engine. Manually Check Oil
Level Reminder to check the oil level.
X Check the oil level at the latest when next refueling
(Y page
252).
X If necessary, add engine oil (Y page
253).
X To confirm the oil check: press and hold 3.
! Avoid longer journeys when there is insufficient engine oil. You
could otherwise damage the engine. 4
Stop Vehicle Turn
Eng. Off The oil level is too low. There is a risk of engine damage.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away ( Y page
138).
X Check the oil level ( Y page
252).
X If necessary, add engine oil (Y page
253).Display messages (vehicles without steering wheel buttons)
205
On-board computer and displays Z

Engine
Display messages
Possible causes/consequences and
M Solutions# An additional warning tone sounds. The battery is not being
charged.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
! Do not drive any further. Otherwise the engine may overheat.
X Secure the vehicle to prevent it from rolling away ( Y page 138).
X Consult a qualified specialist workshop. ?
Coolant Too Hot:
Stop Vehicle Turn
Engine Off An additional warning tone sounds. The coolant is too hot.
G WARNING
Never drive with an overheated engine. Driving when the engine is
overheated can cause 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 hood.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away ( Y page
138).
X Wait until the engine has cooled down.
X Make sure that the air supply to the radiator is not obstructed, by
frozen slush for example.
X Do not start the engine again until the display message goes out
and the coolant temperature is below the maximum value speci-
fied. The engine could otherwise be damaged.
X Monitor the ? coolant temperature gauge in the instrument
cluster.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and at the correct coolant level,
the display may rise to the red mark. Display messages (vehicles with steering wheel buttons)
219
On-board computer and displays Z

Display messages
Possible causes/consequences and
M Solutions? The fan motor is faulty.
X Check the ? coolant temperature gauge in the instrument
cluster.
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 ter-
rain, and stop-start traffic.
Under normal operating conditions and at the correct coolant level,
the display may rise to the red mark. +
Check Coolant
Level See Oper.
Manual The coolant level is too low.
! Avoid longer journeys when there is insufficient coolant in the
engine cooling system. You could otherwise damage the engine.
X Add coolant, making sure to observe the warning notes
(Y page 253).
X Have the engine cooling system checked at a qualified specialist
workshop if the coolant needs to be refilled more often than
usual. 4
Check Engine Oil
At Next Refueling X
Check the oil level at the latest when next refueling
(Y page

252).
X If necessary, add engine oil (Y page
253).
X Have the engine checked at a qualified specialist workshop if you
need to add engine oil more often than usual.
! Avoid longer journeys when there is insufficient engine oil. You
could otherwise damage the engine. 4
Manually Check Oil
Level Reminder to check the oil level.
X Check the oil level at the latest when next refueling
(Y page
252).
X If necessary, add engine oil (Y page
253).
X To confirm the oil check: press a.
! Avoid longer journeys when there is insufficient engine oil. You
could otherwise damage the engine. 4
Eng. Oil Level
Low: Stop Vehicle
Turn Engine Off The oil level is too low. There is a risk of engine damage.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away ( Y page
138).
X Check the oil level ( Y page
252).
X If necessary, add engine oil (Y page
253).220
Display messages (vehicles with steering wheel buttons)
On-board computer and displays

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 Solutions?
N The red coolant warning lamp comes on while the engine is running.
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 malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
X Observe the display messages.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X 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 Do not start the engine again until the coolant temperature is below the maxi-
mum value specified below. The engine could otherwise be damaged.
X Drive 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.?
N The red coolant warning lamp comes on while the engine is running. An addi-
tional warning tone sounds.
The coolant temperature has exceeded the maximum value specified below. 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 adequately and could become damaged.
Never drive with an overheated engine. Otherwise, fluids which may have leaked
into the engine compartment could catch fire.
In addition, steam from an overheated engine can cause serious burns, which
can occur just by opening the hood.
There is a risk of injury.
X Observe the display messages.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine. 234
Indicator and warning lamps in the instrument cluster
On-board computer and displays

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