Display messages
Possible causes/consequences and
M
MSolutions ? The bonnet is open.
A warning tone also sounds.
G WARNING
The open bonnet may then block your view when the vehicle is in
motion.
There is a risk of an accident.
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 Close the bonnet. Active bonnet mal‐ Active bonnet mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The active bonnet (pedestrian protection) is not active due to a mal-
function or because it has already been triggered.
X Consult a qualified specialist workshop. C At least one door is open.
A warning tone also sounds.
X Close all doors. j
Check Check
trailer
trailer hitch
hitch
lock
lock The trailer tow-hitch is not operational.
A warning tone also sounds.
G WARNING
If the ball coupling is not in the locked position, the trailer may come
loose. There is a risk of an accident.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 191).
X Uncouple the trailer and secure it against rolling away.
X Initiate a new swivelling procedure (Y page 274).
X When the display message disappears, re-couple the trailer.
If the display message continues to be displayed: X Do not re-couple the trailer.
X Check the ground clearance and continue driving without the
trailer.
X Consult a qualified specialist workshop. j
Trailer coupling Trailer coupling
extending extending The ball coupling is swivelled out or in.
Only swivel the ball coupling in or out when the vehicle is stationary.
No trailer may be coupled during the swivelling procedure. Do not
attempt to speed up, slow down or initiate the swivelling process using your hand, foot or other aids.
X Move the ball coupling of the trailer tow hitch to an operational
position (Y page 274). 334
Display
messagesOn-board computer and displays
Display messages
Possible causes/consequences and
M
MSolutions &
Pre-entry climate Pre-entry climate
control (via key) control (via key)
available again available again
after engine start after engine start PLUG-IN HYBRID vehicles:
With the engine switched off, you have attempted to switch on the pre-
entry climate control more than twice.
X Let the engine run for ten seconds.
After running the engine, the pre-entry climate control is opera-
tional again. &
Pre-entry climate Pre-entry climate
control (via key) control (via key)
inoperative HV bat‐ inoperative HV bat‐
tery low tery low PLUG-IN HYBRID vehicles:
The on-board voltage is too low. The pre-entry climate control cannot
be switched on.
X Drive for a considerable distance.
The battery charges. When the charge status of the high-voltage
battery is over the specified minimum charge status, pre-entry cli-
mate control is operational again. &
inoperative inoperative
Battery
Battery
low
low The on-board voltage is too low.
The auxiliary heating has switched itself off or cannot be switched on
(Y page 149).
X Drive for a considerable distance.
The battery charges. The auxiliary heating is operational again as
soon as the on-board electrical system voltage is sufficient. &
inoperative Refuel inoperative Refuel
vehicle vehicle There is too little fuel in the fuel tank. The auxiliary heating cannot be
switched on (Y page 149).
X Refuel at the nearest filling station. &
inoperative inoperative
See
SeeOwn‐
Own‐
er's Man.
er's Man. The auxiliary heating is temporarily malfunctioning or faulty.
X When the vehicle is on a level surface and the engine has cooled
down, make up to four attempts to switch on the auxiliary heating,
waiting several minutes between each attempt (Y page 149).
If the auxiliary heating does not switch on: X Consult a qualified specialist workshop. Ð
Power steering mal‐ Power steering mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The power steering assistance is faulty.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident.
X Check whether you are able to apply the extra force required.
If you are able to steer safely:
X Drive on carefully.
X Consult a qualified specialist workshop immediately.
If you are unable to steer safely:
X Do not drive on.
X Consult a qualified specialist workshop. Display
messages
335On-board computer and displays Z
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
M Solutions ÷
N
The yellow ESP ®
warning lamp flashes while the vehicle is in motion.
ESP ®
or traction control has intervened because there is a risk of skidding or at
least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
X Only depress the accelerator pedal as far as necessary when pulling away.
X Accelerate more gently while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
In rare cases (Y page 77) it may be better to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 76). å
N
The yellow ESP ®
OFF warning lamp is lit while the engine is running.
PLUG-IN HYBRID vehicles:
The yellow ESP ®
OFF warning lamp is lit in the READY driving status.
ESP ®
is deactivated.
G WARNING
If ESP ®
is deactivated, ESP ®
is unable to stabilise the vehicle.
Further driving systems or driving safety systems are thus restricted, e.g. Active
Blind Spot Assist. The system does not perform course-correcting braking appli-
cations.
There is an increased danger of skidding and risk of an accident.
X Reactivate ESP ®
.
In rare cases (Y page 77) it may be better to deactivate ESP ®
.
Observe the important safety notes on ESP ®
(Y page 76).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Drive on carefully.
X Contact a qualified specialist workshop immediately and have the ESP ®
system
checked. 344
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
M Solutions ֌
N
The yellow ESP ®
and ESP ®
OFF warning lamps are lit while the engine is running.
PLUG-IN HYBRID vehicles:
The yellow ESP ®
and ESP ®
OFF warning lamps are lit in the READY driving status.
ESP ®
, BAS, BAS PLUS with Cross-Traffic Assist, COLLISION PREVENTION ASSIST
PLUS, ESP ®
trailer stabilisation, PRE‑SAFE ®
, PRE‑SAFE ®
PLUS, PRE‑SAFE ®
Brake,
HOLD function, hill start assist, Crosswind Assist, adaptive brake lights, STEER
CONTROL, Active Lane Keeping Assist and Active Blind Spot Assist, for example,
are unavailable due to a malfunction.
ATTENTION ASSIST is deactivated.
self-diagnosis is not yet complete
G WARNING
The brake system continues to function normally, but without the functions listed above.
The braking distance may thus increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Carefully drive on a suitable stretch of road, making slight steering movements
at a speed above 20 km/h.
The functions mentioned above are available again when the warning lamp goes out.
If the warning lamp is still on: X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. !
N
The red indicator lamp for the electric parking brake flashes or is lit and/or the
yellow warning lamp for the electric parking brake is lit.
X Observe the additional display messages in the multifunction display. 6
N
The red restraint system warning lamp is lit while the engine is running.
The restraint system is faulty.
G WARNING
The airbags or belt tensioners may either be triggered unintentionally or, in the
event of an accident, may not be triggered.
This poses an increased risk of injury.
X Observe the additional display messages in the multifunction display.
X Drive on carefully.
X Contact a qualified specialist workshop immediately and have the restraint sys-
tem checked.
For further information about the restraint system, see (Y page 43).346
Warning and indicator lamps in the instrument clusterOn-board computer and displays
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
approximately 100 mm. The active bonnet is
triggered by pyrotechnics.
For the drive to the workshop, reset the trig-
gered active bonnet yourself. After being reset,
the active bonnet rests in the area of the hinges on the seals, and the hinges do not engage. For
this reason, we recommend that you do not
exceed a maximum permissible speed of
130 km/h on the way to the workshop. If the
active bonnet has been triggered, pedestrian
protection may be limited.
Resetting X
With your hand flat near the hinges (arrows),
push down active bonnet :until it rests on
the seals.
Opening the bonnet 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
When the bonnet is open, and the windscreen wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windscreen wipers and
the ignition before opening the bonnet.
! Make sure that the windscreen wipers are
not folded away from the windscreen. Other- wise, you could damage the windscreen wip-
ers or the bonnet.
X
Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
If you lift the bonnet by approximately 40 cm, the bonnet is opened and held open automat-
ically by the gas-filled strut.
Closing the bonnet X
Lower the bonnet and let it fall from a height
of approximately 20 cm.
X Check that the bonnet has engaged properly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close it
with a little more force. Radiator
Vehicles with a diesel engine: do not cover
the radiator. Do not use thermal mats, insect
protection covers or anything similar. Doing so
can cause the Onboard Diagnostics System to 374
Engine compartmentMaintenance and care
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