
Display messagesPossible causes/consequences and M Solutions?
Coolant Low Stop
Vehicle Turn
Engine OffThe coolant is too hot.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.XWait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.XPay attention to the coolant temperature display.XIf the temperature increases again, visit a qualified specialist
workshop immediately.The poly-V-belt may have torn.XPull 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:
XWait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.XPay attention to the coolant temperature display.XVisit a qualified specialist workshop.GWARNING
Driving when your engine is overheated can cause some fluids which may have leaked into the
engine compartment to catch fire. You could be seriously burned.
Steam from an overheated engine can cause serious burns which can occur just by opening the
engine hood. Stay away from the engine if you see or hear steam coming from it.
Stop the vehicle in a safe location away from other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until the engine has cooled down.
! If the coolant temperature exceeds 248 ‡(120 †) do not continue driving. The engine will
otherwise be damaged.
Display messages405On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions?The engine fan is defective.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.#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 engine oil level at the latest when next refueling
( Y page 457).XIf necessary, add engine oil ( Y page 459).XIf engine oil needs to be added more often than usual, have the
engine checked at a qualified specialist workshop.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 ( Y page 457).XIf necessary, add engine oil ( Y page 457).XIf engine oil needs to be added more often than usual, have the
engine checked at a qualified specialist workshop.
Information on approved engine oils can be obtained from any qualified specialist workshop
or on the Internet at http://www.mbusa.com (USA only).
406Display messagesOn-board computer and displays

! The oil level is too low. Avoid long journeys with too little engine oil. There is a risk of
engine damage.
The display messages and the corresponding symbol that indicate that the oil level is too
low must not be ignored.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 459) and check the oil level
( Y page 457).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 Be MeasuredVehicles without an oil dipstick: the measuring system is
defective.XVisit a qualified specialist workshop.8
Reserve FuelThe 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
Gas Cap LooseThe 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.8
Ultra Low-sulfur
Diesel Fuel OnlyVehicles with a diesel engine: the fuel level has fallen below the
reserve range.XRefuel at the nearest gas station.XOnly use commercially available vehicular ULTRA-LOW SULFUR
HIGHWAY DIESEL FUEL (ULSD, 15 ppm SULFUR MAXIMUM).Display messages407On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions¸·
Replace Air FilterVehicles with a diesel engine: the engine air filter is dirty and must
be replaced.XVisit a qualified specialist workshop.!
Check Fuel FilterVehicles with a diesel engine: there is water in the fuel filter. The
water must be drained off.XVisit a qualified specialist workshop.Ø
Check Additive See
Oper. ManualThe DEF tank is empty.XHave the DEF tank filled as soon as possible at a qualified
specialist workshop ( Y page 321).Ø
Remaining Starts:
16The DEF level has fallen to a minimum.XHave the DEF tank filled immediately at a qualified specialist
workshop. ( Y page 321)
Driving systems
Display messagesPossible causes/consequences and M SolutionsÀ
Attention Assist:
Pause!Based on specific criteria, ATTENTION ASSIST 21
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 21
has failed.XVisit a qualified specialist workshop.Á
Night View Assist
InoperativeNight View Assist Plus is defective.XVisit a qualified specialist workshop.21 Not available on hybrid vehicles.408Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsÁ
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 467).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.Á
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.XApply the electric parking brake.XWait until the display message disappears before pulling away.Display messages409On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsGRisk of accident
AIRMATIC is defective. A warning tone also sounds.
XDo not drive faster than 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.¨
MalfunctionGRisk of accident
The AIRMATIC function is restricted. The vehicle's handling
characteristics may be affected.
XDo not drive faster than 50 mph (80 km/h).XVisit a qualified specialist workshop.ABC
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 faster than 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.410Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsABC
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 faster than 50 mph (80 km/h).XVisit a qualified specialist workshop.HOLD
OffThe HOLD function is deactivated. The vehicle is skidding.
A warning tone also sounds.XReactivate the HOLD function later ( Y page 342).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 342).Radar Sensors
Deactivated See
Oper. ManualThe radar sensor system is deactivated.XSwitch on the radar sensor system ( Y page 387).Lane Keeping
Assist Currently
Unavailable. See
Operator's Manual
or Lane Keeping
Assist Currently
Unavailable. See
Operator's ManualLane Keeping Assist or Active Lane Keeping Assist is deactivated
and temporarily inoperative if:
R the windshield is dirty in the camera's field of vision.
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, for example by dirt
or snow.
Lane Keeping Assist or Active Lane Keeping Assist is operational
again and the display message disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system recognizes that the camera is fully operational again.
If the display message continues to be displayed:XClean the windshield.Lane Keeping
Assist Inoperative
or Active Lane
Keeping Assist
InoperativeLane Keeping Assist or Active Lane Keeping Assist is defective.XVisit a qualified specialist workshop.Display messages411On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsBlind Spot Assist
Currently
Unavailable See
Oper. Manual or
Active Blind Spot
Assist Currently
Unavailable See
Oper. ManualBlind Spot Assist or Active Blind Spot Assist is temporarily
inoperative if:
R the sensors are dirty.
R its 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 9 indicator lamps also light up in the exterior
mirrors.
Blind Spot Assist or Active Blind Spot Assist is operational again
and the display message disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the sensors are fully available again.
R the radar sensor system is back within the operating
temperature range.
If the display message continues to be displayed:XClean the sensors ( Y page 467).XRestart the engine.Blind Spot Assist
Inoperative or
Active Blind Spot
Assist InoperativeBlind Spot Assist or Active Blind Spot Assist is defective.
The yellow 9 indicator lamps also light up in the exterior
mirrors.XVisit a qualified specialist workshop.Parking Guidance
InoperativeParking Guidance is malfunctioning ( Y page 350).XRestart the engine.
If the display message continues to be displayed:
XVisit a qualified specialist workshop.412Display messagesOn-board computer and displays