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Display messages Possible causes/consequences and
M Solutions
b
Switch Off Lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Tur nthe light switch to Ã. Adaptive Highbeam
Assist Inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Adaptive Highbeam
Assist Currently
Unavailable See
Operator's Manual Adaptive Highbeam Assist is deactivated and temporarily
inoperative. Possible causes are:
R
the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
X Cleant he windshield.
If the system detects that the camera is fully operational again,
the Adaptive Highbeam Assist Now Available message is
displayed.
Adaptive Highbeam Assist is operational again. Engine
Display messages Possible causes/consequences and
M Solutions
+
Check Coolant
Level See
Operator's Manual The coolant level is too low.
!
Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Add coolant, observing the warning notes before doing so
(Y page 263).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop. ? The fan motor is faulty.
X
At coolant temperatures under 248 ‡(120 †), drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. 206
Display messagesOn-board computer and displays
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Display messages Possible causes/consequences and
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?
Coolant Too Hot
Stop Vehicle Turn
Engine Off The coolan
tis too hot.
Aw arning tone also sounds.
G WARNING
Do no tdrive when youre ngine is overheated. Thi scan cause some
fluids which may have leaked into the engine compartmen tto
catch fire.
Vapor from the overheated engine can also cause serious burns
which can occu rjust by opening the hood.
There is a ris kofinjury.
X Pull ove rand stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 141).
X Leave the vehicle and kee pasafe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine againu ntil the display message goes out
and the coolant temperature is under 248 ‡ (120 †).
Otherwise, the engine could be damaged.
X Pay attentio nto the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †). Display messages
207On-board computer and displays Z
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Display messages Possible causes/consequences and
M Solutions
# The battery is no
tbeing charged.
Aw arning tone also sounds.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull ove rand stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Ope nthe hood.
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 not damaged:
X Visit a qualified specialist workshop immediately. 4
Check Engine Oil
At Next Refueling The engine oil level has dropped to the minimum level.
Aw
arning tone also sounds.
X Chec kthe oil level when next refueling, at the latest
(Y page 261).
X If necessary, add engine oil (Y page 262).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop. æ
Fuel Level Low The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station. 208
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ç There is only a very small amount of fuel in th
efuel tank.
X Refuel at the neares tgas statio nwithout fail. æ
Gas Cap Loose The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X
Check that the fuel filler cap is correctly closed.
If the fuel filler cap is not correctly closed:
X Close the fuel filler cap.
If the fuel filler cap is correctly closed:
X Visit a qualified specialist workshop. Driving systems
Displa
ymessages Possible causes/consequences and
M Solutions
À
Attention Assist:
Take a Break! Based on certain criteria, ATTENTION ASSIST has detected fatigue
or
alack of concentration on thep art of thedriver. A warning tone
also sounds.
X If necessary, take a break.
During long journeys, take regular breaks in good time so you get
enough rest. À
Attention Assist
Inoperative ATTENTION ASSIST is inoperative.
X
Visi taqualified specialist workshop. ë
Off The HOLD function is deactivated. The vehicle is skidding.
Aw
arning tone also sounds.
X Reactivate the HOLD function later (Y page 160). The HOLD function is deactivated. When the brak
epedal is firmly
depressed, an activation condition is not fulfilled.
Aw arning tone also sounds.
X Check the activation conditions for the HOLD function
(Y page 160). Radar Sensors
Deactivated See
Operator's Manual The radar sensor system is deactivated.
X
Switch on the radar sensor system (Y page 192). Display messages
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Display messages Possible causes/consequences and
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Lane Keeping
Assist Currently
Unavailable See
Operator's Manual Lane Keeping Assis
tis deactivated and temporarily inoperative.
Possible causes are:
R the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the lane markings are worn, dark or covered, e.g. by dirt or snow.
When the causes stated above no longer apply, the display
message disappears.
Lane Keeping Assist is operational again.
If the display message does not disappear:
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 141).
X Cleant he windshield. Lane Keeping
Assist Inoperative Lane Keeping Assist is faulty.
X
Visit a qualified specialist workshop. Blind Spot Assist
Currently
Unavailable See
Operator's Manual Blind Spot Assist is temporarily inoperative. Possible causes are:
R
the sensors are dirty.
R function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
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.
The yellow 9indicator lamps also light up in the exterior
mirrors.
When the causes stated above no longer apply, the display
message disappears.
Blind Spot Assist is operational again.
If the display message does not disappear:
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 141).
X Cleant he sensors (Y page 269).
X Restart the engine. 210
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Blind Spot Assist
Inoperative Blind Spot Assis
tis defective.
The yellow 9indicator lamps also light up in the exterior
mirrors.
X Visit a qualified specialist workshop. Park Assist
Canceled The driver's door is open and the driver's seat belt has not been
fastened.
X
Repeatt he parking process with the seat belt fastened and the
driver's door closed. You have inadvertently touched the multifunction steering wheel
while steering intervention was active.
X
While steering intervention is active, make sure that the
multifunction steering wheel is not touched unintentionally. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 164).Park Assist
Inoperative You have just carried out a large number of turning or parking
maneuvers.
Active Parking Assist will become available again after
approximately ten minutes (Y
page 164).
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Switch off and restart the engine.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. PARKTRONIC is defective.
X
Visit a qualified specialist workshop. DISTRONIC PLUS Off DISTRONIC PLUS has been deactivated (Y
page 152). If it was
deactivated automatically, a warning tone also sounds. DISTRONIC PLUS Now
Available DISTRONIC PLUS is operational again after having been
temporarily unavailable. You can now reactivate DISTRONIC PLUS
(Y
page 152). Display messages
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DISTRONIC PLUS
Currently
Unavailable See
Operator's Manual DISTRONIC PLU
Sis temporarily inoperative. Possible causes are:
R function is impaired due to heavy rain or snow.
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
stations or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
Aw arning tone also sounds.
When the causes stated above no longer apply, the display
message disappears.
DISTRONIC is operational again.
If the display message does notd isappear:
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 141).
X Clean the sensors in the radiator trim (Y page 269).
X Restar tthe engine. DISTRONIC PLUS
Inoperative DISTRONIC PLUS is defective. Adaptive Brake Assist may also
have failed.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. DISTRONIC PLUS
Passive You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X
Remove your foot from the accelerator pedal. DISTRONIC PLUS
--- mph An activation condition for DISTRONIC PLUS is not fulfilled.
X
Check the activation conditions for DISTRONIC PLUS
(Y page 154). 212
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Display messages Possible causes/consequences and
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Cruise Control
Inoperative Cruise control is defective.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. Cruise Control
--- mph Ac
ondition for activating cruise control has not been fulfilled.
You have tried to store aspeed below 20 mph (30 km/h), for
example.
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 150). Display messages
213On-board computer and displays Z