2020 MERCEDES-BENZ METRIS engine

Display messages
Possible causes/consequences and
M Solutions÷
Inoperative
+ ESP
®
, BAS and hill start assist are unavailable due to a malfunction.
ATTENTION ASSIST is deactivated and other driving systems could
be automatically deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
will not stabilize the vehicle.
There is an increased risk of skidding and accidents.
X Switch the engine off, wait briefly and start the engine again.
X Check if the display message has disappeared and ESP ®
is opera-
tional.
X If the display message continues to be displayed:
R Drive on with care.
R Visit a qualified specialist workshop immediately. ÷
Currently Unavail.
+ ESP
®
, BAS and hill start assist are unavailable due to a malfunction.
The self-diagnosis function, for example, may not be complete.
ATTENTION ASSIST is deactivated and other driving systems could
be automatically deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
will not stabilize the vehicle.
There is an increased risk of skidding and accidents.
X Drive on with care on a suitable stretch of road, making make
slight steering movements at a speed above
12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
X Switch the engine off, wait briefly and start the engine again.
X Check if the display message has disappeared and ESP ®
is opera-
tional.
X If the display message continues to be displayed:
R Drive on with care.
R Visit a qualified specialist workshop immediately.200
Display messages (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

Display messages
Possible causes/consequences and
M Solutionsæ
Fuel Level Low The fuel level has dropped to the reserve range.
X Refuel at the nearest gas station. Ï There is very little fuel in the fuel tank.
X Refuel at the nearest gas station without fail. Driving systems
Display messages
Possible causes/consequences and
M Solutions120 km/h!
Maximum Speed
Exceeded Only for certain countries: the maximum speed has been exceeded.
X Drive more slowly. À
Attention Assist
Inoperative ATTENTION ASSIST has failed.
X Visit a qualified specialist workshop. Attention Assist:
Take a Break! Based on certain criteria, ATTENTION ASSIST has detected fatigue
or a lack of concentration on the part of the driver. An additional
warning tone sounds.
X If necessary, take a break.
During long journeys, take regular breaks in good time so that you
get enough rest. Park Assist Can‐
celed Additionally, a warning tone sounds. The active parking assistance
has been canceled and the Active Parking Assist will end automati-
cally. For example, you have touched the steering wheel or driven
too fast.
X Steer and brake yourself.
X If necessary, repeat the parking procedure. Observe the deactiva-
tion conditions as you do so ( Y page
163).Park Assist Inoper‐
ative PARKTRONIC is malfunctioning or faulty.
X Follow the instructions and helpful hints in the "Problems with
PARKTRONIC" section

(Y page 159).
X If the display message continues to be shown, consult a qualified
specialist workshop. Active Parking Assist is unavailable or faulty.
X Switch off the ignition.
X Start the engine again.
X If the display message continues to be shown or symbol j is not
shown in the display, consult a qualified specialist workshop. Display messages (vehicles with steering wheel buttons)
221
On-board computer and displays Z

Display messages
Possible causes/consequences and
M SolutionsCollision Preven‐
tion Assist Inoper‐
ative COLLISION PREVENTION ASSIST PLUS is not available due to a mal-
function.
X Visit a qualified specialist workshop. Collision Preven‐
tion Assist Cur‐
rently Unavail.
See Oper. Manual COLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
R The sensors in the front bumper are dirty.
R The function is impaired due to heavy rain or snow.
R The radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio stations
or other sources of electromagnetic radiation.
R The system is outside the operating temperature range.
R The on-board voltage is too low.
Once the causes listed above no longer apply, the display message
goes out and COLLISION PREVENTION ASSIST is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle, paying attention to road and traffic
conditions.
X Secure the vehicle to prevent it from rolling away (Y page 138).
X Switch off the engine.
X Clean the sensors in the front bumper (Y page
267).
X Restart the engine. Lane Keeping
Assist Inoperative Lane Keeping Assist is faulty.
X Visit a qualified specialist workshop. Lane Keeping
Assist Currently
Unavail. See Oper.
Manual Lane Keeping Assist is deactivated and temporarily inoperative.
Possible causes:
R The windshield is dirty in the camera's field of vision.
R Visibility is impaired due to heavy rain, snow or fog.
R There are no lane markings for an extended period.
R The lane markings are worn away, dark or covered, e.g. by dirt or
snow.
Once the causes listed above no longer apply, the display message
goes out and Lane Keeping Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle, paying attention to road and traffic
conditions.
X Secure the vehicle to prevent it from rolling away (Y page
138).
X Clean the windshield.222
Display messages (vehicles with steering wheel buttons)
On-board computer and displays

Display messages
Possible causes/consequences and
M SolutionsCruise Control
- - - mph A condition for activating cruise control has not been met.
You have tried to store a speed below
20 mph (30 km/h) for exam-
ple.
X If conditions permit, drive faster than 20 mph (30 km/h) and
store the speed.
X Check the activation conditions for cruise control (Y page
147).Blind Spot Assist
Inoperative Blind Spot Assist is faulty.
X Visit a qualified specialist workshop. Blind Spot Assist
Currently Unavail.
See Operator's Man‐
ual Blind Spot Assist is temporarily inoperative. Possible causes:
R You have attached a trailer.
R The sensors in the rear bumper are dirty.
R The function is impaired due to heavy rain or snow.
R The radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio stations
or other sources of electromagnetic radiation.
R The system is outside the operating temperature range.
Once the causes listed above no longer apply, the display message
goes out and Blind Spot Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle, paying attention to road and traffic
conditions.
X Secure the vehicle to prevent it from rolling away ( Y page
138).
X Switch off the engine.
X Clean the sensors in the rear bumper (Y page
267).
X Restart the engine. Display messages (vehicles with steering wheel buttons)
223
On-board computer and displays Z