2012 MERCEDES-BENZ S-Class engine

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 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

Display messagesPossible causes/consequences and M SolutionsParking Guidance
CanceledParking Guidance has been deactivated because:
R the vehicle is skidding.
R the sensors are dirty.
R a malfunction has occurred.XReactivate Parking Guidance later ( Y page 350).
If the parking space symbol is not displayed in the multifunction
display when you are driving at a speed of less than 19 mph
(30 km/h):
XClean the sensors ( Y page 467).XRestart the engine.
If the parking space symbol is still not displayed in the
multifunction display when you are driving at a speed of less than
19 mph (30 km/h):
XVisit a qualified specialist workshop.Parking Guidance has been deactivated because you are no longer
following the recommended path.XPark again and, while doing so, observe the display messages
in the multifunction display.Parking Guidance
FinishedThe vehicle is parked. A warning tone also sounds.
The display message disappears automatically.DISTRONIC PLUS
OffDISTRONIC PLUS has been deactivated ( Y page 332). If it was
deactivated automatically, a warning tone also sounds.DISTRONIC PLUS
Available AgainDISTRONIC PLUS is operational again after having been
temporarily unavailable. You can now reactivate DISTRONIC PLUS
( Y page 332).Display messages413On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsDISTRONIC PLUS
Currently
Unavailable See
Operator's ManualDISTRONIC PLUS is deactivated and is temporarily inoperative if:
R the DISTRONIC PLUS cover in the radiator grill is dirty.
R its 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.
A warning tone also sounds.
DISTRONIC PLUS 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 system is within the operating temperature range.
If the display message continues to be displayed:XClean the DISTRONIC PLUS cover in the radiator grill
( Y page 467).XClean the bumpers ( Y page 467).XRestart the engine.DISTRONIC PLUS
InoperativeDISTRONIC PLUS is defective. BAS PLUS (Brake Assist PLUS) and
PRE-SAFE ®
Brake may be inoperative as well.
A warning tone also sounds.XVisit a qualified specialist workshop.DISTRONIC PLUS
OverrideYou have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.XTake your foot off the accelerator pedal.DISTRONIC PLUS
--- mphAn activation condition for DISTRONIC PLUS is not fulfilled.XCheck the activation conditions for DISTRONIC PLUS
( Y page 332).414Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutionsh
Check Tire PressureGRisk of accident
The tire pressure in one or more tires has dropped significantly.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 513).XCheck the tire pressure. If necessary, correct the tire pressure
( Y page 497).h
Correct Tire
PressureThe tire pressure is too low in at least one of the tires or the tire
pressure difference between the wheels is too great.XCheck the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 497).
Vehicle
Display messagesPossible causes/consequences and M SolutionsShift to P or N
to Start EngineYou have attempted to start the engine with the transmission in
position R or D.XShift the transmission to position P or N.Auxiliary Battery
Malfunction
(White display
message)The auxiliary battery for the automatic transmission is no longer
being charged.XVisit a qualified specialist workshop.Auxiliary Battery
Malfunction
(Red display message)The auxiliary battery for the automatic transmission is discharged.
If there is a malfunction in the vehicle's electrical system, you may
not be able to change the transmission position.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.XConsult a qualified specialist workshop.Apply Brake to
Shift from 'P'You have attempted to move the transmission selector lever to
position D, R or N without depressing the brake pedal.XDepress the brake pedal.Door Open
Vehicle Not in ParkThe driver's door is open and the transmission is in position R, N
or D.XShift the transmission to position P.XApply the electric parking brake.Display messages417On-board computer and displaysZ

SmartKeyDisplay messagesPossible causes/consequences and M SolutionsÂ
Key Does Not
Belong to VehicleYou have put the wrong SmartKey in the ignition lock.XUse the correct SmartKey.Â
Take Your Key From
IgnitionThe SmartKey is in the ignition lock.XRemove the SmartKey.Â
Obtain a New KeyThe SmartKey needs to be replaced.XVisit a qualified specialist workshop.Â
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 82).Â
Don't Forget Your
KeyThe display message is shown for a maximum of 60 seconds and
is only a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.XRemember to take the KEYLESS-GO key with you when you
leave the vehicle.Â
Key Not Detected
(Red display message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the electric parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the electric parking brake.XOperate the vehicle with the SmartKey in the ignition lock.Display messages419On-board computer and displaysZ