key MERCEDES-BENZ R-Class 2011 W251 Repair Manual

dehumidification function remains on. Air-
recirculation mode remains deactivated.
or
XPress the ^ button.
or
XPress the à button.
or
XTurn the temperature control clockwise or
counter-clockwise.
or
XPress the K or I button.
Defrosting the windows
Windows fogged up on the inside
XActivate the "cooling with air
dehumidification" function Á.XActivate automatic mode Ã.XIf the windows continue to fog up, activate
the defrosting function ( Y page 142).
i
You should only select this setting until
the windshield is clear again.
Windows fogged up on the outside
XSwitch on the windshield wipers.XPress the P/\ 21
or O /c 21
air distribution button.
i You should only select this setting until
the windshield is clear again.
Rear window heating
Activating/deactivating
GWarning
Any accumulation of snow and ice should be
removed from the rear window before driving.
Visibility could otherwise be impaired,
endangering you and others.
The rear window heating has a high current
draw. You should therefore switch it off as
soon as the window is clear as it only switches
off automatically after several minutes.
If the battery voltage is too low, the rear
window heating may switch off.XTurn the SmartKey to position 2 in the
ignition lock.XPress the ª button.
The indicator lamp in the ª button lights
up or goes out.
Problems with the rear window heating
If the indicator lamp in the ª rear window
heating button flashes, the on-board voltage
is too low or the roof is open. The rear window
heating has deactivated itself prematurely or
cannot be activated.
XSwitch off any consumers that are not
required, e.g. reading lamps or interior
lighting.
When the battery is sufficiently charged,
the rear window heating is activated again
automatically.
Activating/deactivating air-
recirculation mode
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle
from outside. The air already inside the
vehicle will then be recirculated.
The operation of the air-recirculation mode is
the same for all control panels.
GWarning
Fogged windows impair visibility,
endangering you and others. If the windows
begin to fog on the inside, switching off the
air recirculation mode immediately should
clear interior window fogging. If interior
window fogging persists, make sure the air
conditioning is activated, or press the ¬
button.
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XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the d button.
The indicator lamp in the d button lights
up.
i Air-recirculation mode is activated
automatically at high outside
temperatures. When air-recirculation mode
is activated automatically, the indicator
lamp in the d button is not lit.
Outside air is added after about 30
minutes.
XTo deactivate: press the d button.
The indicator lamp in the d button goes
out.
i Air-recirculation mode switches off
automatically:
R after approximately five minutes if
outside temperatures are under about
41 ‡ (5 †)
R after approximately five minutes if
cooling with air dehumidification is
deactivated
R after approximately 30 minutes if outside
temperatures are over about
41 ‡ (5 †)
i The air-recirculation mode does not
switch off automatically if outside
temperatures exceed 79 ‡ (26 †). After
about 30 minutes, outside air will be
added. 22
Switching the residual heat on/off
It is possible to make use of the residual heat
of the engine to continue heating the
stationary vehicle for up to 30 minutes after
the engine has been switched off. The heating
time depends on the temperature that has
been set.
i The blower will run at a low speed
regardless of the airflow setting.
i If you activate the "residual heat" function
at high temperatures, only the ventilation
will be activated. The blower runs at
medium speed.XTurn the SmartKey to position 0 in the
ignition lock or remove it.XTo switch on: press the Á button.
The indicator lamp in the Á button lights
up.XTo switch off: press the Á button.
The indicator lamp in the Á button goes
out.
i Residual heat is deactivated
automatically:
R after about 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R if the coolant temperature is too low
Setting the air vents
Important safety guidelines
GWarning
When operating the climate control, the air
that enters the passenger compartment
through the air vents can be very hot or very
cold (depending on the set temperature). This
could cause burns or frostbite to unprotected
skin in the immediate area of the air vents.
Always keep sufficient distance between
unprotected parts of the body and the air
vents. If necessary, use the air distribution
adjustment to direct the air to air vents in the
vehicle interior that are not in the immediate
area of unprotected skin.
22 Vehicles with multi-zone automatic climate control.144Setting the air ventsClimate control
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SmartKey positions
SmartKeygTo remove the SmartKey1Power supply for some consumers, such
as the windshield wipers2Ignition (power supply for all consumers)
and drive position3To start the engine
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. The indicator lamps of the low-beam
headlamps, high-beam headlamps or the turn
signal lamps only light up if the low-beam
headlamps, high-beam headlamps or turn
signal lamps are switched on. If an indicator
lamp does not light up when the ignition is
switched on, check it and replace it if
necessary. If an indicator lamp does not go
out after the engine is started or if it lights up
while the vehicle is in motion, see
( Y page 236).
XRemove the SmartKey when the engine is
switched off.
The battery may otherwise discharge.
If you cannot turn the SmartKey in the ignition
lock, the vehicle battery may not be charged
sufficiently.
XCheck the vehicle battery and charge if
necessary ( Y page 310).
or
XJump-start the vehicle ( Y page 311).
i
The SmartKey can be turned in the
ignition lock even if it is not the correct
SmartKey for the vehicle. The ignition is not
switched on. The engine cannot be started.
KEYLESS-GO
Vehicles with KEYLESS-GO are equipped with
a SmartKey with an integrated KEYLESS-GO
function and a detachable Start/Stop button.
The Start/Stop button must be inserted in the
ignition lock and the SmartKey must be in the
vehicle.
Pressing the Start/Stop button several times
in succession corresponds to the different
key positions in the ignition lock. This is only
the case if you are not depressing the brake
pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts
immediately.
The Start/Stop button can be removed from
the ignition lock. Then you can insert the
SmartKey in the ignition lock.
i You do not have to remove the Start/Stop
button from the ignition lock when you
leave the vehicle. However, you should
always take the SmartKey with you when
leaving the vehicle. The vehicle can be
started with the Start/Stop button and the
electrical equipment can be operated while
the SmartKey is in the vehicle.
:Start/Stop button;Ignition lockXInsert Start/Stop button : into ignition
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iWhen you insert Start/Stop button :
into ignition lock ;, the system requires a
detection time of two seconds before you
can use Start/Stop button :.XShift the transmission to position P.XDo not press the brake pedal.
Start/Stop button
=USA only?Canada onlyXPosition 0: if Start/Stop button : has not
yet been pressed, this corresponds to the
SmartKey being removed from the ignition.XPosition 1: press Start/Stop button :.
You can now activate the windshield
wipers, for example.
i If you then open the driver's door when in
this position, the power supply is
deactivated.
XPosition 2 (ignition): press Start/Stop
button : twice.
i
If you press Start/Stop button : once
when in this position and the driver's door
is open, the power supply is deactivated
again.
As soon as the ignition is switched on, all the
indicator lights in the instrument cluster light
up. The indicator lamps of the low-beam
headlamps, high-beam headlamps or the turn
signal lamps only light up if the low-beam
headlamps, high-beam headlamps or turn
signal lamps are switched on. If an indicator
lamp does not light up when the ignition is
switched on, check it and replace it if
necessary. If an indicator lamp does not go
out after the engine is started or if it lights up
while the vehicle is in motion, see
( Y page 236).
Starting the engine
Important safety instructions
GWarning
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.
! Do not depress the accelerator pedal
when starting the engine.
Automatic transmission
XShift the transmission to position P.
i
The transmission position display in the
multifunction display shows P.
Starting procedure with the SmartKey
XTo start a gasoline engine: turn the
SmartKey to position 3 in the ignition lock
( Y page 149) and release it as soon as the
engine is running.XTo start a diesel engine: turn the
SmartKey to position 2 in the ignition lock
( Y page 149).
The % preglow indicator lamp in the
instrument cluster lights up.XWhen the % preglow indicator lamp
goes out, turn the SmartKey to position 3 150DrivingDriving and parking
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(Y page 149) and release it as soon as the
engine is running.
i You can start the engine without preglow
if the engine is warm.
Using KEYLESS-GO to start the engine
GWarning!
As long as the SmartKey is in your vehicle, the
vehicle can be started. Therefore, never leave
children unattended in the vehicle, as they
could otherwise accidentally start the engine.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Do
not leave children unattended in the vehicle,
or with access to an unlocked vehicle. A
child's unsupervised access to a vehicle could
result in an accident and/or serious personal
injury.
i The Start/Stop button can be used to
start the vehicle without inserting the
SmartKey in the ignition lock. The
SmartKey must be in the vehicle.
XThe Start/Stop button must be inserted in
the ignition lock.
i To start the engine with the SmartKey
instead of with KEYLESS-GO, remove the
Start/Stop button from the ignition lock.
XDepress the brake pedal and keep it
depressed.XTo start a gasoline engine: press the
Start/Stop button ( Y page 149) once.
The engine starts.XTo start a diesel engine: press the Start/
Stop button ( Y page 149) once.
Preglow is activated and the engine starts.
i If the engine is warm, the preglow time is
shortened.
Pulling away
Automatic transmissionGWarning
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.
i It is only possible to shift the transmission
from position P to the desired position if
you depress the brake pedal. Only then is
the parking lock released. If you do not
depress the brake pedal, you can move the
DIRECT SELECT selector lever but the
parking lock remains engaged.
XDepress the brake pedal and keep it
depressed.XShift the transmission to position D or R.XWait until the gear change is completed
before pulling away.XRelease the parking brake ( Y page 167).XRelease the brake pedal.XCarefully depress the accelerator pedal.
!
If a warning tone sounds and the
Release Park. Brake message appears
in the instrument cluster, the parking brake
is still applied. Release the parking brake.
i The vehicle locks centrally once you have
pulled away. The locking knobs in the doors
drop down.
You can open the doors from the inside at
any time.
You can also deactivate the automatic
locking feature ( Y page 208).
i Upshifts take place at higher engine
speeds after a cold start. This helps the
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catalytic converter to reach its operating
temperature more quickly.
Hill start assist
Hill start assist helps you when pulling away
forwards or in reverse on an uphill gradient.
It holds the vehicle for a short time after you
have removed your foot from the brake pedal.
This gives you enough time to move your foot
from the brake pedal to the accelerator pedal
and depress it before the vehicle begins to
roll.
GWarning
Never leave the vehicle when it is held by hill
start assist. After approximately one second,
hill start assist will no longer brake your
vehicle and it could roll away.
XTake your foot off the brake pedal.
i Once you have taken your foot off the
brake pedal, the vehicle is held for around
one second.
XPull away.
Hill start assist will not function if:
R you are pulling away on a level road or a
downhill gradient.
R the transmission is in position N.
R the parking brake is applied.
R ESP ®
is malfunctioning.
Switching off the engine
Important safety instructions
GWarning
Do not turn off the engine before the vehicle
has come to a complete stop. With the engine
not running, there is no power assistance for
the brake and steering systems. In this case,
it is important to keep in mind that a
considerably higher degree of effort is
necessary to brake and steer the vehicle.
i If you cannot turn off the engine as
described here, see "Emergency engine
shut down" ( Y page 317).
Vehicles with automatic transmissionGWarning!
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.
XShift the transmission to position P.
Using the SmartKey
XTurn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.XApply the parking brake firmly.
i If you turn off the engine with the
SmartKey and then remove it from the
ignition lock or open a front door, the
automatic transmission switches to P
automatically.
Using KEYLESS-GO
XPress the Start/Stop button (Y page 149).
When the driver's door is closed, the Start/
Stop button is in position 1. When the
driver's door is opened, the Start/Stop
button moves to position 0. This
corresponds to removing the SmartKey.XApply the parking brake firmly.
i If you turn off the engine with the Start/
Stop button and open a front door, the
automatic transmission switches to P
automatically.
i The engine can be turned off while the
vehicle is in motion by pressing and holding
the Start/Stop button for three seconds.
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If you have started the engine with the Start/
Stop button and it cannot be switched off as
described:Xremove the Start/Stop button from the
ignition lock.Xinsert the SmartKey into the ignition lock.
The engine stops. The ignition lock is in
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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.XTurn the SmartKey back to position 0 in the ignition lock before
the next attempt to start with the SmartKey.XBefore the next starting attempt with KEYLESS-GO: shut all open
vehicle doors so that the signals from the SmartKey may be
better received.
or
XPull the Start/Stop button out of the ignition.XUse the SmartKey to start the engine, (Y page 150) as external
radio signals cause KEYLESS-GO to malfunction. 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.The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the starter battery is too
weak or discharged.XJump-start the vehicle ( Y page 311).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop.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.154DrivingDriving and parking
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Engaging park position PXPush the DIRECT SELECT lever in the
direction of the arrow P.
i
Vehicles with a production date as of 18
January 2010: if you open the driver's door
when the vehicle is stationary or if the
speed is very low, the automatic
transmission shifts to park position P
automatically.
! 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.
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.
When the engine is switched off, the
automatic transmission shifts to N
automatically.
Remaining in neutral N
If you wish to keep the automatic
transmission in neutral N, e.g. to wash the
vehicle in a car wash with a towing device,
observe the following:
Using the SmartKey:
R make sure 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 the ignition is switched on.
R when the vehicle is stationary, depress the
brake pedal and keep it depressed.
R shift to 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 DXPush the DIRECT SELECT lever down past
the first point of resistance.
Transmission position display
The current transmission position is shown in
the multifunction display.
:Transmission position
i The arrows in the transmission position
display show how and into which
transmission positions you can change
using the DIRECT SELECT lever.
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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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