
Display messages
Possible causes/consequences and
M
MSolutions Wheel sensor(s)
Wheel sensor(s)
missing missing There is no signal from the tyre pressure sensor of one or several
wheels. The pressure of the affected tyre is not displayed in the mul-
tifunction display.
X Have the faulty tyre pressure sensor replaced at a qualified spe-
cialist workshop. Tyre Tyre
press.
press. monitor
monitor
inoperative No
inoperative No
wheel sensors wheel sensors The wheels fitted do not have suitable tyre pressure sensors. The tyre
pressure monitor is deactivated.
X Fit wheels with suitable tyre pressure sensors.
The tyre pressure monitor is activated automatically after driving for
a few minutes. Tyre Tyre
press.
press. monitor
monitor
inoperative
inoperative The tyre pressure monitor is faulty.
X Consult a qualified specialist workshop. Vehicle
Display messages
Possible causes/consequences and
M
MSolutions To start engine,
To start engine,
shift to either P shift to either P
or N or N You have attempted to start the engine with the transmission in posi-
tion Ror D.
X Shift the transmission to position Por N. Apply
Apply
brake
braketo
todese‐
dese‐
lect Park (P) posi‐
lect Park (P) posi‐
tion tion You have attempted to shift the transmission to position
D,Ror N
without depressing the brake pedal.
X Depress the brake pedal. To shift out of P
To shift out of P
or or
N,
N,depress
depress brake
brake
and start engine
and start engine With the engine switched off, you have attempted to shift the trans-
mission out of position Por Ninto another transmission position.
X Depress the brake pedal.
X Start the engine. Risk of vehicle
Risk of vehicle
rolling Transmis‐ rolling Transmis‐
sion not in P sion not in P The driver's door is open/not fully closed and the transmission is in
position R,Nor D.
A warning tone also sounds.
G WARNING
The vehicle may roll away.
There is a risk of an accident.
X Shift the transmission to position P.
X Secure the vehicle against rolling away (Y page 191).
X Close the driver's door fully. Only select Park Only select Park
(P) (P)
when
when vehicle
vehicle is
is
stationary
stationary The vehicle is moving.
X
Stop the vehicle safely as soon as possible, paying attention to road
and traffic conditions.
X Shift the transmission to position P.332
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Telephone
Telephone
No
Noservice
service Your vehicle is outside the network provider's transmitter/receiver
range.
X Wait until the mobile phone operational readiness symbol appears
in the multifunction display. ¥
Top up washer fluid Top up washer fluid The washer fluid level in the washer fluid reservoir has dropped below
the minimum.
X Top up the washer fluid (Y page 377).Wiper malfunction‐
Wiper malfunction‐
ing ing The windscreen wipers are defective.
X Consult a qualified specialist workshop. Hazard warning
Hazard warning
lamps malfunction‐ lamps malfunction‐
ing ing The hazard warning lamps are faulty.
X Consult a qualified specialist workshop. Key
Display messages
Possible causes/consequences and
M
MSolutions Â
Key Key
does
does not
notbelong
belong
to vehicle
to vehicle You have put the wrong key in the ignition lock.
X Use the correct key. Â
Replace key Replace key The key needs to be replaced.
X Consult a qualified specialist workshop. Â
Change Change
key
keybatteries
batteries The key battery is discharged.
X Change the battery (Y page 87).Â
Key not detected Key not detected
(white display message) The key is currently undetected.
X Change the location of the key in the vehicle.
If the key still cannot be detected:
X Operate the vehicle with the key in the ignition lock if necessary. Â
Key not detected Key not detected
(red display message) The key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle cen-
trally or start the engine.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 191).
X Locate the key. 336
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Because there is interference from a strong source of radio waves, the
key is not detected whilst the engine is running.
A warning tone also sounds.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 191).
X Insert the key into the ignition lock and bring into key mode. Â
Remove Remove
starting
starting but‐
but‐
ton,
ton, then
theninsert
insert key
key R
The key detection function has a temporary malfunction or is faulty.
R The key is continually undetected.
A warning tone also sounds.
X Insert the key into the ignition lock and turn it to the desired posi-
tion.
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
General notes
Some systems carry out a self-diagnosis when the ignition is switched on. Several warning and
indicator lamps can thereby temporarily light up or flash. This behaviour is non-critical. These
warning and indicator lamps only indicate a malfunction if they light up or flash after the engine is started or during a journey. Safety
Seat belts Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ü
N
Only for certain countries: the red seat belt warning lamp lights up for 6 seconds
after the engine starts.
The seat belt warning lamp reminds the driver and front passenger to fasten their
seat belts.
X Fasten your seat belt (Y page 47).ü
N
Only for certain countries: the red seat belt warning lamp lights up after the
engine starts. In addition, a warning tone sounds for up to 6 seconds.
The driver's seat belt is not fastened.
X Fasten your seat belt (Y page 47).
The warning tone ceases. Wa
rning and indi cator lamps in the instrument cluster
337On-board computer and displays Z

Engine
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ;
N
The yellow engine diagnostics warning lamp lights up while the engine is run-
ning.
There may be a fault, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engine may be running in
emergency mode.
X Consult a qualified specialist workshop immediately.
Vehicles with a diesel engine: the fuel tank has been run dry (Y page 179).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emergency running
mode is cancelled. The vehicle need not be checked. 8
N
The yellow reserve fuel warning lamp is on while the engine is running.
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level drops into the
reserve range.
X Refuel at the nearest filling station. ?
N
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gauge is at the start of the scale.
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 Safeguard the vehicle against rolling away (Y page 191).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
347On-board computer and displays Z

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
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 additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 191).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and top up the coolant, observing the warning notes
(Y page 376).
X If you have to top up the coolant frequently, have the engine cooling system
checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by frozen
slush.
X Do not start the engine again until the coolant temperature is below 120 †. The
engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-start traffic. ?
N
The red coolant warning lamp comes on while the engine is running.
The coolant temperature has exceeded 120 †. 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 sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine is overheated
can cause some 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 bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 191).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and top up the coolant, observing the warning notes
(Y page 376).
X If you have to top up the coolant frequently, have the engine cooling system
checked. 348
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions X
Make sure that the air supply to the engine radiator is not blocked, e.g. by frozen
slush.
X If the coolant temperature is below 120 †, you can continue driving to the
nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-start traffic. Driving systems
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ·
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. A warning
tone also sounds.
You are approaching a vehicle, a pedestrian or a stationary obstacle in your line of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to brake or take
evasive action.
Further information on DISTRONIC PLUS (Y page 207).
Further information on PRE ‑SAFE®
Brake (Y page 78).
For further information on the distance warning function of COLLISION PREVEN-
TION ASSIST PLUS, see (Y page 73). Warning and indicator lamps in the instrument cluster
349On-board computer and displays Z

display inaccurate values. Some of these values
are legally required and must always be correct. Engine oil
General notes Depending on your driving style, the vehicle
consumes up to 0.8 litres of oil per 1,000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently drive
at high engine speeds.
Depending on the engine, the oil dipstick may be installed at a different location.
When checking the oil level:
R park the vehicle on a level surface.
R the engine should be switched off for approx-
imately five minutes if the engine is at normal operating temperature.
R if the engine is not at normal operating tem-
perature, e.g. if the engine was only started
briefly, wait approximately 30 minutes before
carrying out the measurement.
Checking the oil level using the oil dip-
stick G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. Example: vehicles with a petrol engine
Example: vehicles with a diesel engine
X Pull dipstick :out of the dipstick tube.
X Wipe off oil dipstick :.
X Slowly slide oil dipstick :into the guide tube
to the stop, and take it out again.
If the level is between MIN mark =and MAX
mark ;, the oil level is correct.
X If the oil level has dropped to MIN mark =or
below, top up with 1.0 l of engine oil.
Topping up engine oil G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. Engine compartment
375Maintenance and care Z

Only check the coolant level if the vehicle is
on a level surface and the engine has cooled
down.
X Turn the key to position 2in the ignition lock
(Y page 158).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 160).
X Check the coolant temperature gauge in the
multifunction display.
The coolant temperature must be below
70 †.
X Turn the key to position 0in the ignition lock
(Y page 158).
X Slowly turn cap :half a turn anti-clockwise
and allow excess pressure to escape.
X Turn cap :further anti-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank ;.
If the coolant level is approximately 1.5 cm
above marker bar =in the filler neck when
warm, there is enough coolant in coolant
expansion tank ;.
X If necessary, top up with coolant that has
been tested and approved by Mercedes-Benz.
X Replace cap :and turn it clockwise as far as
it will go.
Further information on coolant (Y page 441).
Topping up the windscreen washer sys- tem G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
If windscreen washer concentrate comes into contact with hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury. Make sure the windscreen washer concen-
trate does not come into contact with the filler
neck. Example: washer fluid reservoir
X
To open: pull cap:upwards by the tab.
X Top up with the premixed washer fluid.
X To close: press cap :onto the filler neck
until it engages.
If the washer fluid level drops below the recom- mended minimum of 1 litre, a message appears in the multifunction display prompting you to
top up the washer fluid (Y page 336).
Further information on windscreen washer fluid
(Y page 442). ASSYST PLUS
Service message
The ASSYST PLUS service interval display
informs you of the next service due date.
Information on the type of service and service
intervals (see the separate Service Booklet).
You can obtain further information from a
Mercedes-Benz Service Centre.
i The ASSYST PLUS service interval display
does not show any information on the engine oil level. Observe the notes on the engine oil
level (Y page 375).
The multifunction display shows a service mes-
sage for a few seconds, e.g.:
R Service A in .. days
Service A in .. days
R Service A due Service A due
R Service A overdue by .. days
Service A overdue by .. days ASSYST PLUS
377Maintenance and care Z