2011 MERCEDES-BENZ M-Class check engine

XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XVehicles with the AIRMATIC package:
select highway level.XVehicles with the adaptive damping
system: set ADS to AUTO or COMF .XSwitch off the engine.XClose all doors and the tailgate.XCouple up the trailer.XEstablish all electrical connections.
i
Vehicles with the AIRMATIC package:
with a trailer attached, the vehicle will
always remain at highway level. When
coupling up a trailer, please observe the
following:
R if highway level has not been set
manually, the vehicle will automatically
sink to highway level as soon as it
reaches a speed of 5 mph (8 km/h).
R high-speed level is not available.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Towing a trailer
There are numerous legal requirements
concerning the towing of a trailer, e.g. speed
restrictions. Make sure that your vehicle/
trailer combination complies with the local
requirements not only in your area of
residence but also at any location to which
you are traveling. The police and local
authorities can provide reliable information.
Please observe the following when towing a
trailer:
R To acquaint yourself with driving with a
trailer and with the resulting changes to
handling, you should practice cornering,
stopping and reversing in a traffic-free
location.
R Before driving, check:
- the trailer coupling
- the safety switch for braked trailers
- the safety chains
- the electrical connections
- the lights
- the wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer features electronically
controlled brakes, pull away the vehicle/
trailer combination carefully, manually
brake using the brake controller, and check
the brakes for correct function.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion.
R If you couple up a trailer, regularly check
the cargo for secure fastening and make
sure that the trailer lamps and (if
applicable) the trailer brakes are
functioning correctly.
R Bear in mind that the handling will be less
stable when towing a trailer than when
driving without one. Avoid sudden steering
movements.
R The vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
R If possible, avoid abrupt braking. Depress
the brake pedal moderately at first, so that
the trailer can activate its own brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission continues to
shift back and forth between two gears
when driving up or downhill, restrict the
shift range. Select shift range 4, 3, 2, or 1.
A lower gear and lower speed reduce the
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Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
Important safety guidelines
You will find an illustration of the instrument
cluster in the "At a glance" section
( Y page 28).
GWarning
A driver's attention to the road and traffic
conditions must always be his/her primary
focus when driving.
For your safety and the safety of others,
selecting features through the multifunction
steering wheel should only be done by the
driver when traffic and road conditions permit
it to be done safely.
Bear in mind that at a speed of just 30 mph
(approximately 50 km/h ), your vehicle is
covering a distance of 44 feet (approximately
14 m) every second.
GWarning!
No messages will be displayed if either the
instrument cluster or the multifunction
display is inoperative.
As a result, you will not be able to see
information about your driving conditions,
such as
R speed
R outside temperature
R warning/indicator lamps
R malfunction/warning messages
R failure of any systems
Driving characteristics may be impaired.
If you must continue to drive, do so with added
caution. Contact an authorized Mercedes-
Benz Center as soon as possible.GWarning!
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
GWarning
Malfunction and warning messages are only
indicated for certain systems and are
intentionally not very detailed. The
malfunction and warning messages are
simply a reminder with respect to the
operation of certain systems. They do not
replace the owner's and/or driver's
responsibility to maintain the vehicle's
operating safety. Have all required
maintenance and safety checks performed on
the vehicle. Bring the vehicle to an authorized
Mercedes-Benz Center to address the
malfunction and warning messages.
Displays and operation
Tachometer
The red band in the tachometer indicates the
engine's overrevving range.
! Do not drive in the overrevving range, as
this could damage the engine.
The fuel supply is interrupted to protect the
engine when the red band is reached.
Outside temperature display
The outside temperature display is in the
multifunction display.
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Display messagesPossible causes/consequences and M Solutions$
(USA only)
J
(Canada only)
EBV, ABS, ESP
Inoperative See
Operator's ManualGRisk of accident
EBD (Electronic Brake-force Distribution), ABS (Anti-lock Brake
System), ESP ®
(Electronic Stability Program) and therefore also
PRE-SAFE ®
are not available due to a malfunction. BAS (Brake
Assist) is 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.
XDrive on carefully.XVisit a qualified specialist workshop immediately.#
Brake WearThe brake pads/linings have reached their wear limit.XVisit a qualified specialist workshop.$
(USA only)
!
(Canada only)
Release Parking
BrakeYou are driving with the parking brake engaged. A warning tone
also sounds.XRelease the parking brake.$
(USA only)
J
(Canada only)
Check Brake Fluid
LevelGRisk of accident
There is insufficient brake fluid in the brake fluid reservoir. In
addition, the red warning lamp $(USA only) or J (Canada
only) in the instrument cluster lights up and a warning tone sounds.
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.XEngage the parking brake.XConsult a qualified specialist workshop.XDo not add brake fluid. This will not rectify the malfunction.GWarning
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have
your brake system checked immediately.
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.
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Display messagesPossible causes/consequences and M Solutionsb
Daytime Running
Light Left
or
Daytime Running
Light RightThe left or right-hand daytime running light is defective.XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Active Headlamps
InoperativeThe active light function is faulty.XVisit a qualified specialist workshop.b
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 215).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 285).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.
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The display messages and the corresponding symbol that indicate that the coolant level is
too low must not be ignored.Display messagesPossible causes/consequences and M Solutions?
Coolant Stop car,
switch 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 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 OK:
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.
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Display messagesPossible causes/consequences and M Solutions?The engine fan 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-start driving.#The battery is not being charged.
Possible causes are:
R a faulty 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 OK:
XVisit a qualified specialist workshop.#
Battery/
Alternator Stop
VehicleThe battery is faulty.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.XEngage the parking brake.XConsult a qualified specialist workshop.4
Check engine oil
level at next
refuelingThe oil level is too low.XCheck the oil level ( Y page 283).XIf necessary, add the engine oil ( Y page 284).XHave the engine checked for leaks if engine oil has to be added
more often than usual.
Information on approved engine oils can be obtained from any qualified specialist workshop
or on the Internet at http://www.mbusa.com (USA only).
! 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.
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Display messagesPossible causes/consequences and M SolutionsCThere is only a small amount of fuel in the fuel tank.XRefuel at the nearest gas station.8
Reserve FuelThe fuel level has fallen below the reserve range.
The fuel tank must be filled up to at least the reserve fuel level;
otherwise, engine running may be impaired.XRefuel at the nearest gas station.8
Gas 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.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.8
Ultra Low-sulfur
Diesel Fuel OnlyVehicles with a diesel engine: the fuel level has fallen below the
reserve range.XCheck that the fuel filler cap is correctly closed.XRefuel at the nearest gas station.XOnly use commercially available vehicular ULTRA-LOW SULFUR
DIESEL FUEL (ULSD, 15 ppm SULFUR MAXIMUM).¸
Replace air filterVehicles with a diesel engine: the engine air filter is contaminated
and must be replaced. XVisit a qualified specialist workshop.·
Clean 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
Operator's ManualThe AdBlue ®
tank is empty.XHave the AdBlue ®
tank filled as soon as possible at a qualified
specialist workshop ( Y page 156).
Visit a qualified specialist workshop.Ø
Remaining Starts:
20The AdBlue ®
level has fallen to a minimum.XHave the AdBlue ®
tank filled as soon as possible at a qualified
specialist workshop ( Y page 156).
Visit a qualified specialist workshop.236Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsÆ
Reduce speed to
under 12 MPHGRisk of accident
You are exceeding the speed permissible for the selected off-road
level.
XAdjust your driving style to the altered handling characteristics.XOnly make slight steering movements and avoid fast steering
movements.XTake account of the altered handling characteristics.XDo not driver faster than 12 mph(20 km/h).8
Locking System
Inoperative
Service RequiredThe differential locks are faulty. XDo not drive faster than 50 mph (80 km/h).XHave the vehicle checked at a qualified specialist workshop.8
Diff. Lock System
Overheated - Wait
brieflyThe differential locks are too hot and have been disengaged.XDrive on carefully.XAllow the differential locks to cool down.
The differential locks reengage as soon as they have cooled
down.8
Stop vehicle,
engage parking
brakeA gearshift process has been canceled. LOW RANGE is in the
neutral position. There is no connection between the engine and
the drive wheels.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake. Do not continue driving under any
circumstances.XRepeat the gearshift process.Å
Service Required
If parked engage
pk. brakeThe LOW RANGE system is malfunctioning. XDo not drive faster than 50 mph (80 km/h).XEngage the parking brake to park.XHave the vehicle checked at a qualified specialist workshop.Å
Max. Speed 25 MPHYou have exceeded the maximum speed for the gearshift process.XDrive slower.
The gearshift process is carried out.Å
Max. Speed 40 MPHYou have exceeded the maximum speed for the gearshift process.XDrive slower.
The gearshift process is carried out.238Display messagesOn-board computer and displays
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