Engine
Display messages Possible causes/consequences and
M Solutions
+
Top
up coolant See
Owner's Manual The coolant level is too low.
X
Top up the coolant, observing the warning notes before doing
so (Y page 268).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ?
Coolant Stop vehi‐
cle Switch engine
off The coolant is too hot.
X
Pull ove rand stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Make sure tha tthe air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Wait until the display message disappears before restartingt he
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately. The poly-V-belt may have torn.
X
Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the bonnet.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! do not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is OK:
X Wait until the display message disappears before restartingt he
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X Visit a qualified specialist workshop. ? The fan motor is faulty.
X
If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. 224
Display messagesOn-board computer and displays
Display messages Possible causes/consequences and
M Solutions
# The battery is no
tbeing charged.
Possible causes are:
R a faulty alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the bonnet.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! do not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is OK:
X Visit a qualified specialist workshop. 4
Check eng. oil
lev. when next
refuelling The engine oil level has dropped to a critical level.
Aw
arning tone also sounds.
X Chec kthe oil level (Y page 267).
X If necessary, top up the engine oil (Y page 268).
X Have the engine checked for leaks if the engine oil needs top-
ping up more often than usual. 8
Reserve fuel level The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. C There is only a very small amount of fuel in the fuel tank.
The auxiliary heating cannot be operated.
X
Refuel at the nearest filling station without fail. ¸
Replace
air cleaner Vehicles with a diesel engine: the engine air filter is dirty and must
be replaced.
X
Visit a qualified specialist workshop. !
Clean
the fuel fil‐
ter Vehicles with a diesel engine: there is water in the fuel filter. The
water must be drained off.
X
Visit a qualified specialist workshop. Display messages
225On-board computer and displays Z
Display messages Possible causes/consequences and
M Solutions
DISTRONIC PLUS
currently unavail‐
able See Owner's
Manual DISTRONIC PLU
Sis deactivated and is temporarily inoperative if:
R the DISTRONIC PLUS cover in the radiator grille is dirty.
R the sensors in the bumpers are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R its function is impaired due to heavy rain or snow.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
Aw arning tone also sounds.
DISTRONIC PLU Sis operational againa nd the display message
disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects tha tthe sensors are fully available again.
R the system is within the operating temperature range.
If the display message continues to be displayed:
X Clean the DISTRONIC PLUS cover in the radiator grille
(Y page 274).
X Cleant he bumpers (Y page 274).
X Restart the engine. DISTRONIC PLUS
inoperative DISTRONIC PLUS is faulty. BAS PLUS and PRE-SAFE
®
Brake may
also have failed.
Aw arning tone also sounds.
X Visi taqualified specialist workshop. DISTRONIC PLUS
suspended You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X
Take your foot off the accelerator pedal. DISTRONIC PLUS
--- km/h An activation condition for DISTRONIC PLUS is not fulfilled.
X
Check the activation conditions for DISTRONIC PLUS
(Y page 154). DISTRONIC PLUS and
SPEEDTRONIC
inoperative DISTRONIC PLUS and SPEEDTRONIC are faulty. A warning tone
also sounds.
X
Visit a qualified specialist workshop. Cruise control and
SPEEDTRONIC
inoperative Cruise control and SPEEDTRONIC are faulty.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. Display messages
231On-board computer and displays Z
Display messages Possible causes/consequences and
M Solutions
h
Tyre pressure Cau‐
tion, tyre malf. G
Risk of accident
The tyre pressure in one or more tyres has dropped suddenly.
Aw arning tone also sounds.
X Stop the vehicle without making any sudde nsteering or braking
manoeuvres .Pay attentio nto the traffic conditions as you do
so.
X If necessary, change a wheel (Y page 309).h
Tyre pressure
Check tyre(s) G
Risk of accident
The tyre pressure in one or more tyres has dropped significantly.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do
so.
X If necessary, change a wheel (Y page 309).
X Check the tyre pressure. If necessary, correc tthe tyre pressure
(Y page 307). h
Please
correct the
tyre pressure The tyre pressure is too low in at least one of the tyres or the tyre
pressure difference between the wheels is too great.
X
Check the tyre pressures at the next opportunity. If necessary,
correct the tyre pressure (Y page 307).Vehicle
Display messages Possible causes/consequences and
M Solutions
To start engine,
shift to P or N You have attempted to start the engine with the transmission in
position
Ror D.
X Shift the transmission to position Por N. Auxiliary battery
malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X
Visit a qualified specialist workshop. Apply brake to
deselect Park (P)
position You have attempted to move the transmission selector lever to
position
D,Ror Nwithout depressing the brake pedal.
X Depress the brake pedal. 234
Display messagesOn-board computer and displays
Problem Possible causes/consequences and
M Solutions
å
The yellow ESP
®
OFF
warning lamp is lit while
the engine is running. G
Risk of accident
ESP ®
is deactivated. ESP ®
will not stabilise the vehicle if it starts
to skid or if a wheel starts to spin.
X Reactivate ESP ®
.
Exceptions: (Y page 58).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. M
AMG vehicles only:
The yellow SPORT han-
dling mode warning
lamp is lit while the
engine is running.
G
Risk of accident
SPORT handling mode is activated. ESP ®
only stabilises the vehi-
cle in extreme situations. ESP ®
intervention may not be able to
provide sufficient assistance in such situations and the vehicle
may start to skid.
X Reactivate ESP ®
.
Exceptions: (Y page 58).
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. ֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. G
Risk of accident
ESP ®
, BAS, BAS PLUS, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD
function, hill start assist and the adaptive brake lights are not
available due to a malfunction .ESP ®
will not stabilise the vehicle
if it starts to skid or if a wheel starts to spin.
The brake system continues to function normally, bu twithout the
functions listed above.
ATTENTION ASSIST is deactivated.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 6
The red SRS warning
lamp is lit while the
engine is running.
G
Risk of injury
The restraint systems are malfunctioning. The airbags or belt ten-
sioners may either be triggered unintentionally or, in the even tof
an accident, no tbe triggered at all.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. Warning and indicator lamps in the instrument cluster
243On-board computer and displays Z
Engine
Problem Possible causes/consequences and
M Solutions
;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
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 the fuel system
The emission limit values may be exceeded and the engin emay
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. ;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
Vehicles with a diesel engine: the fuel tan
khas been run dry
(Y page 146).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need no tbe
checked. 8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the
star
toft he 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
Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions. Do not continue
driving under any circumstances.
X Apply the parking brake.
X Consult a qualified specialist workshop. 244
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be mal-
functioning.
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 Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Allow the engine and coolant to cool.
X Check the coolant level and top up the coolant (Y page 268).
Observe the warning notes.
X If the coolant needs topping up more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
The engine is not being cooled sufficiently and may be damaged.
X
Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Allow the engine and coolant to cool.
X Check the coolant level and top up the coolant (Y page 268).
Observe the warning notes.
X If the coolant needs topping up more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. Warning and indicator lamps in the instrument cluster
245On-board computer and displays Z
X
Pull release lever :on the bonnet.
The bonnet is released.
! Make sure that the windscreen wipers are
not folded away from the windscreen .Oth-
erwise, you could damage the windscreen
wipers or the bonnet. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
Closing the bonnet G
Risk of injury
Make sure tha tnobody can become trapped
as you close the bonnet.
X Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Engine oil
Notes on the oil level Depending on driving style, the vehicle con-
sumes a maximum of 0.8 l oil per 1000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently
drive at high engine speeds.
Checking the oil level using the oil dip-
stick
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
approximately five minutes if the engine is
at normal operating temperature. Example: vehicles with a petrol engine
Example: vehicles with a diesel engine
X
Pull oil dipstick :out of the oil dipstick
tube.
X Wipe off oil dipstick :. Engine compartment
267Maintenance and care Z