MERCEDES-BENZ R-Class 2012 W251 Owner's Manual
Manufacturer: MERCEDES-BENZ, Model Year: 2012, Model line: R-Class, Model: MERCEDES-BENZ R-Class 2012 W251Pages: 368, PDF Size: 15.19 MB
Page 151 of 368

Problems with the engineProblemPossible causes/consequences and M SolutionsThe engine does not
start. The starter motor
can be heard.R There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.XBefore attempting to start the engine again, turn the SmartKey
in the ignition back to position 0 or press the Start/Stop button
repeatedly until all indicator lamps in the instrument cluster go
out.XTry to start the engine again ( Y page 146). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak
or discharged.XJump-start the vehicle ( Y page 313).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The starter motor was exposed to a thermal load that was too high.XAllow the starter motor to cool down for approximately two
minutes.XTry to start the engine again.
If the engine still does not start:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.Driving149Driving and parkingZ
Page 152 of 368

ProblemPossible causes/consequences and M SolutionsVehicles with a
gasoline engine:
The engine is not
running smoothly and
is misfiring.There is a malfunction in the engine electronics or a mechanical
component of the engine management system.XOnly depress the accelerator pedal slightly.XHave the cause rectified immediately at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz Center.
Otherwise, non-combusted fuel may get into the catalytic
converter and damage it.The coolant
temperature gauge
shows a value above
248 ‡ (120 †).The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.XStop as soon as possible and allow the engine and the coolant
to cool down.XCheck the coolant level ( Y page 285). Observe the warning
notes as you do so and add coolant if necessary.Automatic transmission
Important safety notes
GWARNING
It is dangerous to shift the automatic
transmission out of parking position P or
neutral position N if the engine speed is
higher than idle speed. If your foot is not firmly
on the brake pedal, the vehicle could
accelerate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and when
your right foot is firmly on the brake pedal.
GWARNING
Keep in mind that turning off the engine alone
only will shift the automatic transmission into
neutral position N automatically.
Always shift the automatic transmission into
park position P before turning off the engine.
Otherwise the vehicle could roll away which
could result in an accident and/or serious
personal injury.
DIRECT SELECT lever
Overview of transmission positions
The DIRECT SELECT lever is on the right of the
steering column.
PPark position with parking lockRReverse gearNNeutralDDrive
i The DIRECT SELECT lever always returns
to its original position. The current
transmission position P, R , N or D appears
in the transmission position display
( Y page 151) in the multifunction display.
150Automatic transmissionDriving and parking
Page 153 of 368

Engaging park position PXPush the DIRECT SELECT lever in the
direction of arrow P.
i
The automatic transmission shifts
automatically into park position P if you
open the driver's door when the vehicle is
stationary or driving at very low speed, and
the transmission is in position D or R.
! If the engine speed is too high or the
vehicle is moving, do not shift the
automatic transmission directly from D to
R , from R to D or directly to P. The
automatic transmission could otherwise be
damaged.
Engaging reverse gear R
! Only shift the automatic transmission to
R when the vehicle is stationary.
XWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever up past the
first point of resistance.
Shifting to neutral N
XWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever up or down
to the first point of resistance.
If the engine has been switched off, the
automatic transmission automatically
switches to N.
Remaining in neutral N
If the automatic transmission is to remain in
neutral N, e.g. for washing the vehicle in car
washes with a towing device, please observe
the following instructions:
GWARNING
When leaving the SmartKey in the starter
switch, do not leave children unattended in
the vehicle. It is possible for children to switch
on the ignition which could result in
unsupervised use of vehicle equipment.
Unsupervised use of vehicle equipment could
result in an accident and/or serious personal
injury.
Using the SmartKey:
R make sure that the ignition is switched on.
R when the vehicle is stationary, depress the
brake pedal and keep it depressed.
R shift to neutral N.
R release the brake pedal.
R if applied, release the parking brake.
R switch off the ignition and leave the
SmartKey in the ignition lock.
Using KEYLESS-GO:
R make sure that the ignition is switched on.
R when the vehicle is stationary, depress the
brake pedal and keep it depressed.
R engage park position P.
R release the brake pedal.
R remove the Start/Stop button from the
ignition lock.
R insert the SmartKey into the ignition lock.
R switch on the ignition.
R depress the brake pedal and keep it
depressed.
R shift to neutral N.
R release the brake pedal.
R if applied, release the parking brake.
R switch off the ignition and leave the
SmartKey in the ignition lock.
Shifting to transmission position DXWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever down past
the first point of resistance.
Transmission position display
The current transmission position is shown in
the multifunction display.
Automatic transmission151Driving and parkingZ
Page 154 of 368

:Transmission position
iThe arrows in the transmission position
display show how and into which
transmission positions you can change
using the DIRECT SELECT lever.
Transmission positions
BPark position
Do not shift the transmission into
position P(Y page 163) unless the
vehicle is stationary. The parking
lock should not be used as a brake
when parking. In addition to
engaging the parking lock, you
must always apply the parking
brake to secure the vehicle.
If the vehicle electronics are
malfunctioning, the transmission
may be locked in position P.
Have the vehicle electronics
checked at a qualified specialist
workshop, e.g. an authorized
Mercedes-Benz Center,
immediately.CReverse gear
Only shift the transmission to R
when the vehicle is stationary.ANeutral
Do not shift the transmission to N
while driving. The transmission
could otherwise be damaged.
No power is transmitted from the
engine to the drive wheels.
Releasing the brakes will allow you
to move the vehicle freely, e.g. to
push it or tow it.
If ESP ®
is deactivated or faulty:
only shift the transmission to
position N if the vehicle is in danger
of skidding, e.g. on icy roads.
! Rolling in neutral N can damage
the drive train.7Drive
The automatic transmission
changes gear automatically. All
forward gears are available.
Changing gear
The automatic transmission shifts to the
individual gears automatically when it is in
transmission position D. This automatic
gearshifting behavior is determined by:
R a shift range restriction, if selected
R the selected drive program
E/S (Y page 153)
R the position of the accelerator pedal
R the road speed
152Automatic transmissionDriving and parking
Page 155 of 368

Driving tips
Kickdown
Use kickdown for maximum acceleration.
XVehicles for USA: fully depress the
accelerator pedal.
The transmission shifts to a lower gear
depending on the engine speed.XVehicles for Canada: depress the
accelerator pedal beyond the pressure
point.
The transmission shifts to a lower gear
depending on the engine speed.
Rocking the vehicle free
Rocking the vehicle free by shifting back and
forth between transmission positions D and
R can help to free a vehicle that has become
stuck in mud or snow. The engine
management system of the vehicle limits
shifting back and forth between transmission
positions D and R to a maximum speed of
5 mph (9 km/h). To shift back and forth
between transmission positions D and R,
move the selector lever up and down beyond
the pressure point.
Working on the vehicle
GWARNING
When working on the vehicle, engage the
parking brake and shift the automatic
transmission into park position P. Otherwise
the vehicle could roll away which could result
in an accident and/or serious personal injury.
Trailer towing
XWhen towing a trailer and driving downhill,
shift to the lower gear if the automatic
transmission constantly shifts between
two gears.XEngaging a lower gear and reducing the
speed reduces the risk of the engine
overheating.Program selector button
General information
The program selector button allows you to
choose between different driving
characteristics.
Program selector button
E EconomyComfortable, economical
drivingS SportSporty driving style
i
For further information on the automatic
drive program, see ( Y page 154).
XPress program selector button :
repeatedly until the letter for the desired
gearshift program appears in the
multifunction display.
Steering wheel paddle shifters
:Left-hand steering wheel paddle shifter;Right-hand steering wheel paddle shifterAutomatic transmission153Driving and parkingZ
Page 156 of 368

You can restrict or derestrict the shift range
by using the steering wheel paddle shifters.
Automatic drive program
Drive program E is characterized by the
following:
R the vehicle pulling away more gently in
forward and reverse gears, unless the
accelerator pedal is depressed fully
R increased sensitivity. This improves driving
stability on slippery road surfaces, for
example
R the automatic transmission shifting up
sooner. This results in the vehicle being
driven at lower engine speeds and the
wheels being less likely to spin
Drive program S is characterized by the
following:
R sporty engine settings
R the vehicle pulling away in first gear
R the automatic transmission shifting up
later
R the fuel consumption possibly being higher
as a result of the later automatic
transmission shift points
Shift ranges
Introduction
When the automatic transmission is in
position D, it is possible to restrict or
derestrict the shift range ( Y page 154).
The shift range selected is shown in the
multifunction display. The automatic
transmission shifts only as far as the selected
gear.
Driving situations=You can use the engine's braking
effect.5To use the braking effect of the
engine on downhill gradients and
for driving:
R on steep mountain roads
R in mountainous terrain
R in arduous conditions4To use the braking effect of the
engine on extremely steep downhill
gradients and on long downhill
stretches
Restricting the shift range
XPull the left-hand steering wheel paddle
shifter.
The automatic transmission shifts down
one gear and restricts the shift range to the
relevant gear.
i If the engine exceeds the maximum
engine speed when shifting down, the
automatic transmission protects against
engine damage by not shifting down.
i If the maximum engine speed for the shift
range is reached and you continue to
accelerate, the automatic transmission
shifts up in order to prevent the engine
from overrevving, even if the shift range is
restricted.
Derestricting the shift range
XPull the right-hand steering wheel paddle
shifter.
The shift range is derestricted.
Clearing the shift range restriction
XPull and hold the right-hand steering wheel
paddle shifter until D is shown again in the
multifunction display.
The automatic transmission shifts from the
current shift range directly to D.154Automatic transmissionDriving and parking
Page 157 of 368

Selecting the ideal shift rangeXPull the left-hand steering wheel paddle
shifter and hold it in position.
The automatic transmission shifts to the
gear which allows optimum acceleration
and deceleration. To do this, the automatic
transmission shifts down one or more
gears.Automatic transmission155Driving and parkingZ
Page 158 of 368

Problems with the transmissionProblemPossible causes/consequences and M SolutionsThe transmission has
problems shifting gear.The transmission is losing oil.XHave the transmission checked at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz Center,
immediately.The acceleration ability
is deteriorating.
The transmission no
longer changes gear.The transmission is in emergency mode.
It is only possible to shift into second 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 second gear; if R is
selected, the transmission shifts into reverse gear.XHave the transmission checked at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz Center,
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 a qualified specialist
workshop 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 notes
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
156RefuelingDriving and parking
Page 159 of 368

to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.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 a
small quantity of the wrong fuel will
damage the fuel system and engine.
! Do not switch on the ignition if you
accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the 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.
! Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection
system could be blocked by particles from
the fuel can.
i Only refuel with premium-grade unleaded
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 more information under “Fuel”
( Y page 356), or by contacting an
authorized Mercedes-Benz Service 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.
! Use a filter when adding fuel from a fuel
can. Otherwise, the fuel lines and/or the
fuel injection system could be blocked by
particles from the fuel can.
i 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 more information under “Fuel”
( Y page 356), or by contacting an
authorized Mercedes-Benz Service Center
or 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
Refueling157Driving and parkingZ
Page 160 of 368

obtained from oil companies, e.g. at gas
stations.
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 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.XRemove the SmartKey from the ignition
lock.
KEYLESS-GO: open the driver’s door. This
switches the ignition to position 0, which
corresponds to having removed the
SmartKey. 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 pump nozzle into the
filler neck 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.XClose the fuel filler flap.
i If you drive with the fuel filler cap open,
the reserve fuel warning lamp flashes. In
addition, the ! (USA only) or ;
(Canada only) Check Engine warning lamp
may light up. A message appears in the
multifunction display ( Y page 228).
For further information on warning and
indicator lamps in the instrument cluster,
see ( Y page 244).
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.
Fuel filler flap emergency 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 in the cargo
compartment behind the side trim on the
right-hand side, when viewed in the direction
of travel.
158RefuelingDriving and parking