engine MERCEDES-BENZ R-Class 2011 W251 Workshop Manual

Problems with the transmissionProblemPossible causes/consequences and M SolutionsThe acceleration ability
is deteriorating.
The transmission no
longer changes gear.The transmission is in emergency mode.
It is only possible to shift into 2nd gear and reverse gear.XStop the vehicle.XShift the transmission to position P.XSwitch off the engine.XWait at least 10 seconds before restarting the engine.XShift the transmission to position D or R.
If D is selected, the transmission shifts into 2nd gear; if R is
selected, the transmission shifts into reverse gear.XHave the transmission checked at a qualified specialist
workshop immediately.Transfer case
The vehicle has permanent 4-wheel drive
(4MATIC). Power is always transmitted to
both axles.
! Performance tests may only be carried
out on a 2-axle dynamometer. The brake
system or transfer case could otherwise be
damaged. Contact an authorized
Mercedes-Benz Center for a performance
test. Mercedes-Benz recommends that you
use an authorized Mercedes-Benz Center
for this purpose.
! If the parking brake is being tested on a
brake dynamometer, the ignition must be
switched off (SmartKey or Start/Stop
button in position 0 or 1), as ESP ®
will
otherwise automatically intervene. The test
must last a maximum of 10 seconds. The
brake system could otherwise be damaged.Refueling
Important safety guidelines
GWarning!
Gasoline and diesel fuels are highly flammable
and poisonous. They burn violently and can
cause serious injury.
Never allow sparks, flames or smoking
materials near gasoline or diesel fuel!
Turn off the engine before refueling.
Whenever you are around gasoline or diesel
fuel, avoid inhaling fumes and any skin or
clothing contact. Extinguish all smoking
materials.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging your
health.
GWarning
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gasoline
to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.
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GWarning!
Do not fill diesel tanks with gasoline. Do not
mix diesel fuel with gasoline. Otherwise the
fuel system and engine could be damaged. In
addition, the vehicle could catch fire.
! Do not use gasoline to refuel vehicles with
a diesel engine. Do not use diesel to refuel
vehicles with a gasoline engine. Even small
amounts of the wrong fuel result in damage
to the fuel system and engine.
! Do not start the engine if you accidentally
refuel with the wrong fuel. Otherwise, the
fuel could enter the fuel lines. This would
require draining of the fuel tank and fuel
lines. Notify a qualified specialist workshop
and have the fuel tank and fuel lines
drained completely.
Gasoline
Fuel grade
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
i Only refuel with unleaded premium-grade
gasoline with a specified minimum octane
number of 91 (average value of 96 RON/
86 MON).
Usually you will find information about the
fuel grade on the pump. If you cannot find
the label on the gasoline pump, ask the gas
station staff.
You can find further information under
"Fuel" ( Y page 352), by consulting an
authorized Mercedes-Benz Center or
visiting http://www.mbusa.com (USA
only).
Diesel
Fuel grade
! Only refuel with ULTRA-LOW SULFUR
DIESEL FUEL (ULSD, 15 ppm SULFUR
MAXIMUM). Using other diesel fuels could
result in increased wear and damage to the
engine and/or exhaust system.
Never refuel with marine diesel or heating
oil.
Do not mix these fuels with diesel fuels and
do not use any special additives, as this
may result in damage.
! When refueling using a fuel can, use a
filter or use a clean cloth as a filter.
Otherwise, particles from the fuel can may
block the fuel lines and/or the diesel
injection system.
i Refuel only with ULTRA-LOW SULFUR
DIESEL FUEL (ULSD, 15 ppm SULFUR
MAXIMUM).
Usually you will find information about the
fuel grade on the pump. If you cannot find
the label on the gasoline pump, ask the gas
station staff.
You can find further information under
"Fuel" ( Y page 352), by consulting an
authorized Mercedes-Benz Center or by
visiting http://www.mbusa.com (USA
only).
Low outside temperatures
! Do not use gasoline to refuel vehicles with
a diesel engine. Never mix diesel with
gasoline or kerosene, as this may result in
damage to the engine or fuel system.
Diesel fuel with improved cold flow properties
is available during the winter months. Further
information on fuel properties can be
obtained from oil companies, e.g. at gas
stations.
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Refueling
Fuel filler flap
The fuel filler flap is unlocked or locked
automatically when you open or close the
vehicle with the SmartKey or using KEYLESS-
GO.
The position of the fuel filler flap is to the rear
on the right. The position of the fuel filler cap
is displayed in the instrument cluster 8.
The arrow next to the filling pump indicates
the side of the vehicle.
:To open the fuel filler flap;To insert the fuel filler cap=Fuel type?Tire pressure table
Opening
XSwitch off the engine.
i When the engine is running and the fuel
filler flap is open, the yellow reserve fuel
warning lamp and the ! (USA only)
or ; (Canada only) engine diagnostics
warning lamp may light up.
For further information on warning and
indicator lamps in the instrument cluster,
see ( Y page 242).
XRemove the SmartKey from the ignition
lock.
KEYLESS-GO: the driver's door is open.
This returns the ignition to position 0,
which corresponds to the SmartKey beingremoved. The driver's door can be closed
again.XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap opens slightly.XOpen the fuel filler flap.XTurn the fuel filler cap counter-clockwise
and remove it.XInsert the fuel filler cap into the holder
bracket on the inside of filler flap ;.XCompletely insert the filler neck of the fuel
pump nozzle into the tank and refuel.XOnly fill the tank until the pump nozzle
switches off.
! Overfilling the fuel tank could damage the
fuel system.
Closing
XReplace the fuel filler cap and turn it
clockwise. The fuel filler cap audibly
engages.
i Close the fuel filler flap before locking the
vehicle. A locking pin otherwise prevents
the fuel filler flap from closing after the
vehicle has been locked.
XClose the fuel filler flap.
Emergency fuel filler flap release
GWarning!
Avoid contact with the vehicle walls as they
may contain sharp edges. Otherwise, you
could injure yourself while releasing the fuel
filler flap.
The emergency release is located behind the
side trim panel in the cargo compartment.
XOpen the tailgate.XOpen the right-hand side trim panel
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Problems with the fuel and fuel tankProblemPossible causes/consequences and M SolutionsFuel is leaking from the
vehicle.GRisk of explosion or fire
The fuel line or fuel tank is defective.
XTurn the SmartKey to position 0(Y page 149) in the ignition lock
immediately and remove it.XDo not restart the engine under any circumstances.XConsult a qualified specialist workshop.The fuel filler flap
cannot be opened.The fuel filler flap is not released.
or
The SmartKey batteries are discharged.XUnlock the vehicle using the mechanical key ( Y page 77).XOpen the tailgate.XManually unlock the fuel filler flap using the emergency release
( Y page 162).The fuel filler flap is released, but the opening mechanism is
jammed.XManually unlock the fuel filler flap using the emergency release
( Y page 162).XConsult a qualified specialist workshop.The fuel tank in a diesel
engine vehicle has
been run completely
dry and the engine will
not start.There is air in the fuel system.XRefuel the vehicle with at least 5.3 US qt (5 liters) of diesel.XTurn the ignition on for at least 10 seconds. Turn the SmartKey
to position 2(Y page 149) in the ignition lock.XStart the engine continuously for up to 10 seconds until it runs
smoothly.
If the engine does not start:
XTurn the ignition on again for approximately 10 seconds. Turn
the SmartKey to position 2(Y page 149) in the ignition lock.XStart the engine again continuously for up to 10 seconds until
it runs smoothly.
If the engine does not start after three attempts:
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AdBlue®
Important notes on use
BlueTEC exhaust gas aftertreatment 24
must
be operated with AdBlue ®
reducing agent in
order to function properly. Adding AdBlue ®
is
one of the tasks performed during
maintenance. Under normal operating
conditions, a tank of AdBlue ®
lasts until the
next service due date.
When the AdBlue ®
supply has almost run out,
the Check Additive – See Operator's
Manual message is shown in the
multifunction display.
When the AdBlue ®
supply sinks to a minimum
level, the Remaining Starts: 20 message
is shown in the multifunction display.
i When the Remaining Starts: 20
message is shown in the multifunction
display, you can start the engine 20 more
times. If AdBlue ®
is not topped up, it is then
not possible to start the engine again. Top
up the AdBlue ®
tank with approximately
1 gallon (3.8 l) of AdBlue ®
or have the
AdBlue ®
tank refilled at a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
Use the special AdBlue ®
refill bottle when
adding between maintenance intervals. For
more information, please contact an
authorized Mercedes-Benz Center or
Roadside Assistance if applicable
( Y page 20).
Further information about BlueTEC exhaust
gas aftertreatment and AdBlue ®
is available
at any authorized Mercedes-Benz Center.
Adding AdBlue ®GWarning!
Make sure
R AdBlue ®
does not come into contact with
skin, eyes, or clothing
R to keep AdBlue ®
out of the reach of children
If you and/or others have come into contact
with AdBlue ®
:
R If AdBlue ®
has gotten into contact with
eyes, flush with plenty of water immediately
and seek medical help.
R Clean affected skin immediately with plenty
of water.
R If AdBlue ®
was swallowed, rinse mouth
immediately with plenty of water and drink
plenty of water. Consult a physician.
GWarning!
When opening the filler cap of the AdBlue ®
tank ammonia gas vapors may escape. Refill
AdBlue ®
in a well ventilated area only.
Ammonia gas vapors have a pungent odor and
are particularly irritating for your skin,
mucous membranes, and eyes. Inhaling
ammonia gas vapors will cause burning eyes,
nose, and throat, as well as coughing and
watering eyes.
! Only use AdBlue ®
that complies with
ISO 22241. Do not add any special
additives to AdBlue ®
and do not thin
AdBlue ®
with water. This could destroy the
BlueTEC exhaust gas aftertreatment.
! Rinse surfaces that have come into
contact with AdBlue ®
immediately with
water or remove AdBlue ®
using a damp
cloth and cold water. If the AdBlue ®
has
already crystallized, use a sponge and cold
water to clean it. AdBlue ®
residues
crystallize after time and contaminate the
affected surfaces.
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! AdBlue ®
is not a additive and must not be
added to the diesel tank. If AdBlue ®
is
added to the diesel tank this could damage
the engine.
i If you are adding between maintenance
intervals, add approximately 1 gallon (3.8 l)
of AdBlue ®
to the AdBlue ®
tank. 1 gallon
(3.8 l) of AdBlue ®
is approximately
2 AdBlue ®
refill bottles.
Further information about
AdBlue ®
(Y page 353).
The AdBlue ®
filler neck is under the luggage
compartment floor.XSwitch off the ignition.XOpen the tailgate.XLift the luggage compartment floor
( Y page 294).XRemove wheel bolt wrench ; and ratchet
ring spanner = if applicable.XTurn AdBlue ®
cap : anti-clockwise and
remove it.XTurn AdBlue ®
filler cap ; anti-clockwise
and open it.
Filler cap ; is secured with a plastic strap.XTurn AdBlue ®
filler cap ? anti-clockwise
and open it.
Filler cap ? is secured with a plastic strap.XUnscrew the covering cap from AdBlue ®
refill bottle A.XPlace AdBlue ®
refill bottle A on the filler
neck as shown and screw on clockwise
hand-tight.
! Only screw on the AdBlue ®
refill bottle
hand-tight. It could otherwise be damaged.
XPress AdBlue ®
refill bottle A down.
The AdBlue ®
tank is filled. This may take up
to one minute.
i If the AdBlue ®
refill bottle is no longer
pressed down, the filling process stops and
the partially emptied bottle can be
removed.
XRelease AdBlue ®
refill bottle A.XTurn AdBlue ®
refill bottle A anti-clockwise
and remove it.XPlace AdBlue ®
filler cap ? on the filler
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XInsert AdBlue®
cap : as shown and turn
it clockwise as far as it will go.XStow wheel bolt wrench ; and ratchet ring
spanner = again.XFold the load compartment floor down.XClose the tailgate.XDrive at a speed above 10 mph (16 km/h).
The Check Additive – See
Operator's Manual disappears after
approximately one minute.
i If the Check Additive – See
Operator's Manual is still displayed in
the multifunction display, top up with
another bottle of AdBlue ®
.
i Then, have the AdBlue ®
supply checked
and filled completely if necessary.
Mercedes-Benz recommends that you use
a qualified specialist workshop such as an
authorized Mercedes-Benz Center for this
purpose.
Parking
Important safety guidelines
GWarning!
Do not park this vehicle in areas where
combustible materials such as grass, hay or
leaves can come into contact with the hot
exhaust system. These materials could be
ignited and cause a vehicle fire.
Vehicle movement may result in serious
personal injury or damage to the vehicle or
vehicle drivetrain. Therefore, always do the
following before turning off the engine and
leaving the vehicle:
R Keep right foot on the brake pedal.
R Engage the parking brake.
R Shift the automatic transmission into park
position P.
R Slowly release the brake pedal.
R When parked on an incline, always turn the
front wheels towards the road curb.
R Turn the SmartKey in the starter switch to
position 0 and remove the SmartKey from
the starter switch, or press the KEYLESS-
GO start/stop button.
R Take the SmartKey with you and lock the
vehicle when leaving.
Parking brake
GWarning
Engaging the parking brake while the vehicle
is in motion can cause the rear wheels to lock
up. You could lose control of the vehicle and
cause an accident. In addition, the vehicle's
brake lights do not light up when the parking
brake is engaged.
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it with
you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. Children could
release the parking brake and/or shift the
automatic transmission out of park position
P , either of which could result in an accident
and/or serious personal injury.
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XTo apply: depress parking brake ; firmly.
When the engine is running, the $ (USA
only) or J (Canada only) indicator lamp
lights up in the instrument cluster.XTo release: depress the brake pedal and
keep it depressed.XPull release handle :.
When the ignition is switched on or the
engine is running, the $ (USA only) or
J (Canada only) indicator lamp goes out
in the instrument cluster.
Parking up the vehicle
If you leave the vehicle parked up for longer
than four weeks, the battery may be damaged
by exhaustive discharge.
XDisconnect the battery or connect it to a
trickle charger.
i You can obtain information about trickle
chargers from a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center.
If you leave the vehicle parked up for longer
than six weeks, the vehicle may suffer
damage as a result of lack of use.
XVisit a qualified specialist workshop and
seek advice.Driving tips
General driving tips
Important safety instructions
GWarning!
Please do not forget that your primary
responsibility is to drive the vehicle. A driver’s
attention to the road must always be his/her
primary focus when driving. For your safety
and the safety of others, we recommend that
you pull over to a safe location and stop
before placing or taking a telephone call.
If you choose to use the telephone 25
while
driving, please use the hands-free device and
only use the telephone when road, weather
and traffic conditions permit. Some
jurisdictions prohibit the driver from using a
mobile telephone while driving a vehicle.
Only operate the COMAND 25
(Cockpit
Management and Data System) if road,
weather and traffic conditions permit.
Otherwise, you may not be able to observe
traffic conditions and could endanger yourself
and others.
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.
Drive sensibly – save fuel
To save fuel, observe the following notes:
XKeep tires at the recommended inflation
pressures.XRemove unnecessary cargo.XRemove the roof carrier when not in use.XMaintain a low engine speed until the
engine is warm.XAvoid frequent acceleration and
deceleration.XHave all maintenance work performed at
the service intervals specified in the25 Observe all legal requirements.168Driving tipsDriving and parking
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Service Booklet or indicated by the service
interval indicator.
Fuel consumption is also increased by driving
in cold weather, in stop-and-go traffic, on
short trips and in mountainous areas.
Drinking and driving
GWarning
Drinking and driving and/or taking drugs and
driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and
judgment.
The possibility of a serious or even fatal
accident are greatly increased when you drink
or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs.
Pedals
GWarning
Make sure absolutely no objects are
obstructing the pedals' range of movement.
Keep the driver's footwell clear of all
obstacles. If there are any floormats or
carpets in the footwell, make sure that the
pedals still have sufficient clearance.
During sudden driving or braking maneuvers,
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury.
Coasting with the engine switched off
GWarning!
There is no power assistance for the steering
and the brake when the engine is not running.
Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
Exhaust checkGWarning
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the engine in confined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work optimally if they are
maintained exactly in accordance with the
manufacturer's specifications. For this
reason, all work on the engine must be carried
out by qualified and authorized Mercedes-
Benz technicians.
The engine settings must not be changed in
any circumstances. Furthermore, all specific
service work must be carried out at regular
intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Service Booklet.
Engine oil
! Vehicles with a diesel particle filter:
If the vehicle is mostly driven for short
distances, it is possible that malfunctions
may occur during the automatic cleaning of
the diesel particle filter. This can lead to
engine damage. Therefore, if you frequently
drive short distances, make sure to drive
on highways or country roads for 20
minutes at least every 500 km.
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Brakes
Important safety guidelinesGWarning
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control.
GWarning
Make sure that you do not endanger other
road users when you apply the brakes.
Downhill gradients
! On long and steep gradients, you must
reduce the cargo on the brakes by shifting
to a lower gear in good time. This allows
you to take advantage of engine braking
and helps you to avoid overheating the
brakes and wearing them out excessively.
When you take advantage of engine
braking, a drive wheel may not turn for
some time, e.g. on a slippery road surface.
This could cause damage to the drive train.
Such damage is not covered by the
Mercedes-Benz warranty.
Heavy and light loads
GWarning
Depressing the brake pedal constantly results
in excessive and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
If the brakes have been subjected to a heavy
cargo, do not stop the vehicle immediately,
but drive on for a short while. This allows the
airflow to cool the brakes more quickly.
Wet roadsGWarning
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced. You have to depress the brake pedal
more firmly. Maintain a safe distance from
vehicles in front.
After driving on a wet road or having the
vehicle washed, brake firmly while paying
attention to the traffic conditions. This will
warm up the brake discs, thereby drying them
more quickly and protecting them against
corrosion.
Limited braking performance on salt
treated roads
GWarning
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in the
braking effect, resulting in a significantly
longer braking distance, which could lead to
an accident.
To avoid this danger, you should:
R occasionally brake carefully, without
putting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake discs.
Maintenance of the brakes
! If the brake warning lamp lights up in the
instrument cluster and you hear a warning
tone, even though the parking brake has
been released, the brake fluid level may be
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