fuel MERCEDES-BENZ R-Class 2012 W251 User Guide

Warning and indicator lampsFunctionPage:ABS240;The lamp lights up briefly,
but has no function.=Brakes (USA only)239?ESP ®241ADistance warning signal245On vehicles without
DISTRONIC, the lamp lights
up briefly but has no
function.BBrakes (Canada only)239CTire pressure monitor (USA
only)
245
FunctionPageDTurn signal117EESP ®
OFF241FSeat belt238GDiesel engine: preglow146HSRS243ILow-beam headlamps115JCheck Engine (Canada
only)
244
KCheck Engine (USA only)244LHigh-beam headlamps117MReserve fuel24430Instrument clusterAt a glance

Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
The product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
The product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
Locking and unlocking centrally
The SmartKey centrally locks/unlocks:
R the doors
R the tailgate
R the fuel filler flap
:& Locks the vehicle;F Opens/closes the tailgate=% Unlocks the vehicle
When unlocking, the turn signals flash once.
When locking, they flash three times.
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer ( Y page 207).
You can also set an audible signal to confirm
that the vehicle has been locked or unlocked.
The audible signal can be activated and
deactivated using the on-board computer
( Y page 208).XTo unlock centrally: press the %
button.
If you do not open the vehicle within
approximately 40 seconds of unlocking:
R the vehicle is locked again.
R the theft deterrent locking system is armed
again.
XTo lock centrally: press the & button.
KEYLESS-GO
General notes
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
The product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
SmartKey73Opening/closingZ

X To unlock the vehicle: touch the inner
surface of the door handle.XTo lock the vehicle: press locking
button :.XConvenience closing feature: press
locking button : for an extended period
( Y page 88).
If you pull on the handle of the tailgate, only
the cargo compartment of the vehicle is
unlocked.
Changing the settings of the locking
system
You can change the setting of the locking
system in such a way that only the driver's
door and the fuel filler flap are unlocked. This
is useful if you frequently travel on your own.
XTo change the setting: press and hold
down the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
( Y page 76) flashes twice.
i
If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the & or % button
locks or unlocks the vehicle.
The SmartKey now functions as follows:
XTo unlock the driver's door: press the
% button once.XTo unlock centrally: press the %
button twice.XTo lock centrally: press the & button.The KEYLESS-GO function is changed as
follows:XTo unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.XTo unlock centrally: touch the inner
surface of the door handle on the front-
passenger door or the rear door.XTo lock centrally: press the locking button
on one of the door handles.
Restoring the factory settings
XPress the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice.
Mechanical key
General notes
If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered ( Y page 69).
There are several ways to turn off the alarm:
XTo turn the alarm off with the
SmartKey: press the % or & button
on the SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XTo deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the
ignition lock. The SmartKey must be in the
vehicle.
or
XLock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.SmartKey75Opening/closingZ

Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident
Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked. You can only open
the rear doors from inside the vehicle if they
are not secured by the child-proof locks
( Y page 63).
Only open the door when the traffic situation
permits.
If the vehicle was previously locked with the
SmartKey or with KEYLESS-GO, opening the
vehicle from the inside will activate the anti-
theft alarm system. Switch off the alarm
( Y page 69).
XPull door handle ;.
If the door is locked, locking knob : pops
up. The door is unlocked and can be
opened.
Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside.
The central locking/unlocking button does
not lock or unlock the fuel filler flap.
The buttons are located on both front doors.
i You cannot unlock the vehicle centrally
from the inside if the vehicle has been
locked with the SmartKey or KEYLESS-GO.
i It is only possible to lock the vehicle
centrally if the front-passenger door is
closed.XTo unlock: press button :.XTo lock: press button ;.
If all the doors and the tailgate are closed,
the vehicle locks.
You can open a front door from inside the
vehicle even if it has been locked. Only open
the door when the traffic situation permits.
If the vehicle has been locked with the central
locking button:
R and the SmartKey is set to its factory
setting, the entire vehicle is unlocked if a
front door is opened from the inside
R and the SmartKey is set to an individual
setting, only the front door that is opened
from inside the vehicle is unlocked.
If the vehicle has been locked centrally with
the SmartKey or with KEYLESS-GO, it is not
unlocked when the release button for the
central locking is used.
Automatic locking feature
The vehicle locks automatically when the
ignition is switched on and the wheels of the
80DoorsOpening/closing

vehicle are turning at a speed of more than
9 mph (15 km/h).
You could therefore be locked out when:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is being tested on a
dynamometer.
You can switch the automatic locking
function on and off using the on-board
computer ( Y page 208).
Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered ( Y page 69).
XTake the mechanical key out of the
SmartKey ( Y page 75).XInsert the mechanical key into the lock of
the driver's door as far as it will go.XTurn the mechanical key counter-clockwise
as far as it will go to position 1 and hold
it in this position.XPull the door handle beyond the first
resistance.
The locking knob pops up.
The door is unlocked.XTurn the mechanical key back and remove
it.XPull the door handle again.XInsert the mechanical key into the
SmartKey.
Locking the vehicle
If the vehicle can no longer be locked with the
SmartKey, you can lock it by taking the
following steps.
XClose the front-passenger door, the rear
door on the front-passenger side and the
tailgate.XOpen the driver’s door and the rear door on
the driver’s side.XPress the locking button on the driver’s
door ( Y page 80).
The locking knobs in the front-passenger
door and in the rear doors drop down.XPress down the locking knobs in the front-
passenger and rear doors manually, if
necessary.XClose the driver's door from the outside.XPress down the locking knob of the driver's
door by reaching in through the open rear
door.
i Make sure that you have the SmartKey on
your person and that it has not been left in
the vehicle.
XClose the rear door on the driver’s side.XMake sure that the doors and the tailgate
are locked.
i If you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not armed.
Cargo compartment
Important safety notes
Do not leave the SmartKey in the cargo
compartment. You could otherwise lock
yourself out.
Cargo compartment81Opening/closingZ

Useful information ............................144
Breaking-in notes .............................. 144
Driving ............................................... 144
Automatic transmission ...................150
Refueling ............................................ 156
Parking ............................................... 163
Driving tips ........................................ 165
Driving systems ................................ 170
Trailer towing .................................... 191143Driving and parking

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

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

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

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