2011 MERCEDES-BENZ R-Class check engine light

Display messagesPossible causes/consequences and M Solutionsb
AUTO Light
InoperativeThe light sensor is faulty. The low-beam headlamps are switched
on.XUSA only: switch off daytime driving lights in the on-board
computer ( Y page 206).XSwitch the lights on and off using the light switch.XVisit a qualified specialist workshop.b
Switch Off LightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to $ or c .
or
XIf the rear fog lamp is switched on: press the light switch in to
the stop.
Engine
Display messagesPossible causes/consequences and M Solutions+
Top Up Coolant See
Operator's ManualThe coolant level is too low.XAdd coolant, observing the warning notes before doing so
( Y page 281).XIf coolant needs adding more often than usual, have the engine
coolant system checked at a qualified specialist workshop.GWarning
Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may burn
if it comes into contact with hot engine parts. You could be seriously burned.
! The coolant level is too low. Avoid making long journeys with too little coolant in the cooling
system. The engine will otherwise be damaged.
The display messages and the corresponding symbol that indicate that the coolant level is
too low must not be ignored.
224Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsBlind Spot Assist
Currently
Unavailable See
Operator's ManualBlind 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.
R the on-board voltage is too low.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
Blind Spot Assist is operational again and the display message
disappears when:
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 287).XRestart the engine.Blind Spot Assist
InoperativeBlind Spot Assist is faulty.
The yellow 9 indicator lamps also light up in the exterior
mirrors.XVisit a qualified specialist workshop.Cruise Control
InoperativeCruise control is faulty. XVisit a qualified specialist workshop.Cruise Control
--- mph A condition for activating cruise control has not been met.
You wanted to save a speed of less than 20 mph (30 km/h).XIf the situation allows, drive faster than 20 mph (30 km/h) and
save the speed.XCheck the activation conditions for cruise control
( Y page 173).DISTRONIC
--- MPH An activation condition for DISTRONIC is not fulfilled.XIf the situation allows, drive faster than 20 mph (30 km/h) and
save the speed.XCheck activation conditions for DISTRONIC ( Y page 175).Display messages229On-board computer and displaysBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 229Z

GWarning
Driving with the brake warning lamp illuminated can result in an accident. Have your brake system
checked immediately if the brake warning lamp stays on. Do not add brake fluid before checking
the brake system.
Overfilling the brake fluid reservoir can result in spilling brake fluid on hot engine parts and the
brake fluid catching fire. You can be seriously burned.
Seat belt
ProblemPossible causes/consequences and M Solutions7
After starting the
engine, the red seat
belt warning lamp lights
up for 6 seconds.The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.XFasten your seat belt ( Y page 54).7
After starting the
engine, the red seat
belt warning lamp lights
up. In addition, a
warning tone sounds
for up to 6 seconds.GRisk of injury
The driver's seat belt is not fastened.
XFasten your seat belt ( Y page 54).
The warning tone ceases.7
The red seat belt
warning lamp lights up
after the engine starts,
as soon as the driver's
or the front-passenger
door is closed.GRisk of injury
The driver or front passenger has not fastened their seat belt.
XFasten your seat belt ( Y page 54).
The warning lamp goes out.GRisk of injury
There are objects on the front-passenger seat.
XRemove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out.Warning and indicator lamps in the instrument cluster237On-board computer and displaysBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 237Z

Safety systemsProblemPossible causes/consequences and M Solutions!
The yellow ABS warning
lamp is lit while the
engine is running. GRisk of accident
ABS (Anti-lock Brake System) is deactivated due to a malfunction.
Therefore, BAS (Brake Assist), ESP ®
(Electronic Stability Program),
EBD (Electronic Brake-force Distribution) and PRE-SAFE ®
are also
deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic
transmission, will not be available.
!
The yellow ABS warning
lamp is lit while the
engine is running.GRisk of accident
The on-board voltage is too low. ABS has been deactivated due to
undervoltage.
Therefore, ESP ®
, BAS and PRE-SAFE ®
are also deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XSwitch off consumers that are not required, e.g. the rear window
defroster or interior lighting.
ABS will be available again as soon as the vehicle's on-board
electrical system voltage increases.
If the warning lamp is still on:
XHave the battery and alternator checked at a qualified specialist
workshop.!
The yellow ABS warning
lamp is lit while the
engine is running.Self diagnosis is not yet complete.XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).Warning and indicator lamps in the instrument cluster239On-board computer and displaysBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 239Z

EngineProblemPossible causes/consequences and M Solutions! (USA only)
; (Canada only)
The yellow engine
diagnostics warning
lamp lights up while the
engine is running.There may be a malfunction, 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 gasoline engines)
The emission limit values may have been exceeded and the engine
may be breaking in emergency mode.XHave the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you are required to visit a qualified specialist
workshop as soon as the yellow engine diagnostics warning
lamp lights up due to the relevant applicable legislation. If
necessary, check whether this is the case in the state you are
in.
! (USA only)
; (Canada only)
The yellow engine
diagnostics warning
lamp lights up while the
engine is running.The 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.XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.XIf the fuel filler cap is closed: visit a qualified specialist
workshop.Vehicles with a diesel engine: the fuel tank has been run
completely dry and the engine will not start. There is air in the fuel
system ( Y page 164).The yellow reserve fuel
warning lamp lights up
while the engine is
running.The fuel level has fallen below the reserve range.
The fuel tank must be filled at least to the reserve fuel level to
prevent impairment to the running of the engine.XRefuel at the nearest gas station.242Warning and indicator lamps in the instrument clusterOn-board computer and displays
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XPull release lever : on the hood.
The hood is released.
! Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield
wipers or the hood.
XReach into the gap, pull hood catch
handle ; up and lift the hood.
Closing the hood
GWarning
When closing the hood, use extreme caution
not to catch hands or fingers. Be careful that
you do not close the hood on anyone.
Make sure the hood is securely engaged
before driving off. Do not continue driving if
the hood can no longer engage after an
accident, for example. The hood could
otherwise come loose while the vehicle is in
motion and injure you and/or others.
XLower the hood and let it fall from a height
of approximately 8 inches (20 cm).XCheck that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force.
Radiator
i Vehicles with a diesel engine: do not
cover the radiator, for example with a
winter front or bug cover. Otherwise, the
readings of the on-board-diagnostic
system may be inaccurate. Some of these
readings are required by law and must be
accurate at all times.
Engine oil
Notes on the oil level
Depending on the driving style, the vehicle
consumes up to 0.9 US qt (0.8 l) of oil over a
distance of 600 miles (1000 km). The oil
consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds.
When checking the oil level:
R park the vehicle on a level surface.
R the engine should be switched off for at
least five minutes if the engine is at normal
operating temperature.
R the engine should be switched off for at
least 30 minutes if it is not at normal
operating temperature (i.e. if you only start
the engine briefly).
Engine compartment279Maintenance and careBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 279Z

After an accidentProblemPossible causes/consequences and M SolutionsFuel is leaking from the
vehicle.GRisk of explosion or fire
The fuel line or the fuel tank is faulty.
XImmediately turn the SmartKey to position 0 ( Y page 149) in the
ignition lock and remove it.XDo not restart the engine under any circumstances.XConsult a qualified specialist workshop.You are unable to
determine the extent of
the damage.XConsult a qualified specialist workshop.You cannot detect any
damage.XStart the engine as normal.The NECK-PRO head
restraints/NECK-PRO
luxury head restraints
on the driver's and
front-passenger seat
have been triggered.Your vehicle has been involved in a rear-end collision.XReset the NECK-PRO head restraints/NECK-PRO luxury head
restraints ( Y page 53).Where will I find...?
First-aid kit
The first-aid kit can be found under the cargo
compartment floor in the vehicle tool kit
stowage tray. Depending on the vehicle's
equipment, the location of the first-aid kit
may differ slightly from that shown in the
example illustration.
XOpen the tailgate.XLift the cargo compartment floor up
( Y page 294).
Example: vehicles with BlueTEC
XRemove first-aid kit :.
i
Check the expiration date on the first-aid
kit at least once a year. Replace the
contents if necessary, and replace missing
contents.
Where will I find...?293Roadside AssistanceBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 293Z