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EngineDisplay messagesPossible causes/consequences and M Solutions+
Check Coolant
Level See Oper.
ManualThe coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.XAdd coolant, observing the warning notes before doing so
( Y page 424).XIf coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop.Display messages371On-board computer and displaysZ
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Display messagesPossible causes/consequences and M Solutions?The fan motor is faulty.XAt coolant temperatures under 248 ‡ (120 †), drive to the next
qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic.?
Coolant Low Stop
Vehicle Turn
Engine OffThe coolant is too hot.
A warning tone also sounds.GWARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 289).XLeave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.XDo not start the engine again until the display message goes out
and the coolant temperature is under 248 ‡ (120 †).
Otherwise, the engine could be damaged.XPay attention to the coolant temperature display.XIf 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 †).
372Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M Solutions#The battery is not being charged.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronicsXPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XOpen the hood.XCheck whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
XConsult a qualified specialist workshop.
If the poly-V-belt is not damaged:
XVisit a qualified specialist workshop.4
Check Engine Oil
at Next RefuelingVehicles with an oil dipstick: the oil level has dropped to the
minimum level.XCheck the oil level when next refueling, at the latest
( Y page 421).XIf necessary, add engine oil ( Y page 423).XHave 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 or on the Internet at http://
www.mbusa.com (USA only).
4
Check Engine Oil
Level (Add 1
quart) (USA only)
Check Engine Oil
Level (Add 1
Liter) (Canada only)Vehicles without an oil dipstick: the engine oil level is too low.XCheck the oil level when next refueling, at the latest
( Y page 421).XIf necessary, add engine oil ( Y page 423).XHave 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 or on the Internet at http://
www.mbusa.com (USA only).
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Display messagesPossible causes/consequences and M Solutions4
Engine Oil Level
Low Stop Vehicle
Turn Engine OffVehicles without an oil dipstick: the engine oil level is too low.
There is a risk of engine damage.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XApply the parking brake.XAdd engine oil ( Y page 423) and check the oil level
( Y page 421).4
Engine Oil Level
Too HighVehicles without an oil dipstick: you have added too much engine
oil. There is a risk of damage to the engine or to the catalytic
converter.XHave the excess oil siphoned off at a qualified specialist
workshop. Observe the legal requirements.4
Engine Oil Level
Cannot measure
eng. oil levelVehicles without an oil dipstick: the measuring system is
defective.XVisit a qualified specialist workshop.8
Reserve fuel levelThe fuel level has dropped into the reserve range.XRefuel at the nearest gas station.CThere is only a very small amount of fuel in the fuel tank.XRefuel at the nearest gas station without fail.8
Fuel filler cap
openThe fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.XCheck that the fuel filler cap is correctly closed.
If the fuel filler cap is not correctly closed:
XClose the fuel filler cap.
If the fuel filler cap is correctly closed:
XVisit a qualified specialist workshop.374Display messagesOn-board computer and displays
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Driving systemsDisplay messagesPossible causes/consequences and M SolutionsÀ
Attention Assist:
Drowsiness
DetectedBased on specific criteria, ATTENTION ASSIST has determined that
the driver is tired or paying less attention. A warning tone also
sounds.XIf necessary, take a break.
During long journeys, take regular breaks in good time so you get
enough rest.
À
Attention Assist
InoperativeATTENTION ASSIST has failed.XVisit a qualified specialist workshop.Á
Night View Assist
InoperativeNight View Assist Plus is defective.XVisit a qualified specialist workshop.Á
Night View Assist
Currently
UnavailableThe temperature of the camera is too high.XWait until you see the Night View Assist Available
Again display message.
You can also:
XFold the camera cover down ( Y page 432).XAdjust the air distribution of the automatic air conditioning
upwards.Á
Night View Assist
Lights Must Be Set
To AUTO or ONA condition for activating Night View Assist Plus has not been
fulfilled.XTurn the light switch to c or L .Á
Night View Assist
Not In Reverse GearA condition for activating Night View Assist Plus has not been
fulfilled.XShift the transmission to P, N or D.Á
Night View Assist
Lights ON or AUTO,
Not in R GearA condition for activating Night View Assist Plus has not been
fulfilled.XTurn the light switch to c or L .XShift the transmission to P, N or D.Display messages375On-board computer and displaysZ
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Display messagesPossible causes/consequences and M SolutionsÁ
Night View Assist
Only When It Is
DarkYou have attempted to activate Night View Assist Plus in the
daytime.
Night View Assist Plus can only be activated when it is dark.¨
Vehicle RisingYour vehicle is adjusting to the level you have selected.¨
Vehicle Rising
Please Wait BrieflyThe vehicle level is too low when the vehicle is stationary. A
warning tone also sounds.XDo not pull away.
The vehicle level is set when the display message disappears.¨
STOP Car Too LowYou have pulled away while the vehicle level is still too low.
AIRMATIC sets the vehicle to the selected level after a short
period.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 289).XWait until the display message disappears before pulling away.AIRMATIC is defective. A warning tone also sounds.XDo not drive at speeds above 50 mph (80 km/h).XMake only slight steering movements. Otherwise, the front
fender or the tires could be damaged if the steering movement
is too large.XListen for scraping sounds.XPull over and stop the vehicle safely, paying attention to road
and traffic conditions, and select a higher vehicle level.
Depending on the malfunction, it may be possible to raise the
vehicle.XVisit a qualified specialist workshop.¨
MalfunctionThe AIRMATIC function is restricted. The vehicle's handling
characteristics may be affected.XDo not drive at speeds above 50 mph (80 km/h).XVisit a qualified specialist workshop.376Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsABC
Malfunction Stop
VehicleThe ABC (Active Body Control) vehicle level is too low.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
After a few seconds, the vehicle level is adjusted and the display
message disappears.The vehicle is leaking oil.
The display message is shown continuously.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XNotify a qualified specialist workshop or breakdown service.The display message is shown continuously.
ABC is malfunctioning.XDo not drive at speeds above 50 mph (80 km/h).XMake only slight steering movements. Otherwise, the front
fender or the tires could be damaged if the steering movement
is too large.XListen for scraping sounds.XVisit a qualified specialist workshop.ABC
Vehicle Rising
Please Wait BrieflyThe ABC vehicle level is too low when the vehicle is stationary.XDo not pull away.
The vehicle level is set when the display message disappears.ABC
MalfunctionThe ABC function is restricted. The vehicle's handling
characteristics may be affected.XDo not drive at speeds above 50 mph (80 km/h).XVisit a qualified specialist workshop.ë
OffThe HOLD function is deactivated. The vehicle is skidding.
A warning tone also sounds.XReactivate the HOLD function later ( Y page 308).The HOLD function is deactivated. When the brake pedal is firmly
depressed, an activation condition is not fulfilled.
A warning tone also sounds.XCheck the activation conditions for the HOLD function
( Y page 308).Display messages377On-board computer and displaysZ
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Display messagesPossible causes/consequences and M SolutionsRadar Sensors
Deactivated See
Oper. ManualThe radar sensor system is deactivated.XSwitch on the radar sensor system ( Y page 350).Active Lane
Keeping Assist
Currently
Unavailable See
Oper. ManualActive Lane Keeping 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.
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.
If the display message does not disappear:XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSecure the vehicle against rolling away ( Y page 289).XClean the windshield.
If the system detects that the camera is fully operational, the
display message disappears.
Active Lane Keeping Assist is operational again.
Active Lane
Keeping Assist
InoperativeActive Lane Keeping Assist is defective.XVisit a qualified specialist workshop.378Display messagesOn-board computer and displays