
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 140).
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 notes
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.142Setting 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 254).
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 323).
or
XJump-start the vehicle ( Y page 325).
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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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 148) 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 325).
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:
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Using KEYLESS-GOXPress the Start/Stop button (Y page 147).
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.
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
position 0.
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.
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.166ParkingDriving and parking
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12 V sockets
Points to observe before use
! If you are using all sockets in the vehicle,
make sure that you do not exceed the
maximum current draw of 55 A. Otherwise,
you will overload the fuses.
The socket can be used for accessories with
a maximum power consumption of 180 W,
e.g. lamps or chargers for mobile phones.
If you use the socket for long periods when
the engine is switched off, the battery may
discharge.
XTurn the key to position 2 in the ignition
lock.
Socket in the front-passenger footwell
XLift up the cover of socket :.
Socket in the cockpit
!
If accessories are connected, make sure
that a maximum current draw of 15 A is not
exceeded. Otherwise, you will overload the
fuse.
! The socket is not suitable for operating
the electric air pump.
XPress marking =.
Stowage compartment : opens.XRemove cover from socket ;.
i
On vehicles with the smoker's package,
you must remove the cigarette lighter in
order to use the socket ( Y page 280).
Socket in the rear compartment
XLift up the cover of socket :.
Socket in the cargo compartment
The socket is located in the cargo
compartment on the left-hand side trim.
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GWarning
Do not place any metal objects on the battery
as this could result in a short circuit.
Use leak-proof batteries only to avoid the risk
of acid burns in the event of an accident.
Take care that you do not become statically
charged, e.g. by wearing synthetic clothing or
rubbing against textiles. For this reason, you
also should not pull or push the battery over
carpets or other synthetic materials.
Never touch the battery first. First, touch the
outside body of the vehicle in order to release
any possible electrostatic charges.
Do not rub the battery with rags or cloths. The
battery could explode if touched due to
electrostatic charge or due to spark
formation.
! Switch off the engine and remove the
SmartKey before disconnecting the
terminal clamps from the battery. On
vehicles with KEYLESS-GO, make sure that
the ignition is switched off. Check that all
the indicator lamps in the instrument
cluster are off. You may otherwise destroy
electronic components, such as the
alternator.
! Like other batteries, the vehicle battery
may discharge over time if you do not use
the vehicle. In this case, have the battery
disconnected at a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center. You can also charge the
battery with a charger recommended by
Mercedes-Benz. Contact an authorized
Mercedes-Benz Center for further
information.
The battery, breather hose and cover of the
positive terminal clamp must be installed
securely during operation.
i Remove the SmartKey if you park the
vehicle and do not require any electrical
consumers. The vehicle will then use very
little energy, thus conserving battery
power.
Mercedes-Benz recommends that you do not
carry out work on batteries yourself, e.g.
removing, charging or replacing. Always have
this work performed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.
i If the power supply has been interrupted,
e.g. if the battery has been reconnected,
you must carry out the following tasks:
R set the clock ( Y page 222)
On vehicles with COMAND and a
navigation system, the clock is set
automatically.
R reset the sliding sunroof ( Y page 90)
R reset the function for folding the exterior
mirrors in/out automatically by folding
the mirrors out once ( Y page 108)
R reset the side windows ( Y page 87)
Charging the battery
GWarning
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during
charging and cause explosions that may
result in paint damage, corrosion or personal
injury.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for
information and availability.
Charge the battery in accordance with the
separate instructions for the accessory
battery charger.
GWarning!
There is a risk of acid burns during the
charging process due to the gases which
escape from the battery. Do not lean over the
battery during the charging process.
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Towing and tow-starting
Important safety notes
GWarning
If you tow the vehicle, you must use a rigid
towing bar if:
R the engine will not run.
R there is a malfunction in the brake system.
R there is a malfunction in the power supply
or the vehicle's electrical system.
With the engine not running, there is no power
assistance for the brake and steering
systems. You will then need considerably
more force to steer and to brake and the
brake pedal travel will be longer. If necessary,
depress the brake pedal with maximum force.
Before towing away, make sure that the
steering can be moved and is not locked.
If you tow or tow-start another vehicle, its
weight must not exceed the maximum
permissible gross vehicle weight of your
vehicle.
It is better to have the vehicle transported
than to have it towed.
! You may only tow the vehicle a maximum
distance of 30 miles (50 km). A towing
speed of 30 mph (50 km/h) must not be
exceeded.
For towing distances over 30 miles
(50 km), the vehicle must loaded onto a
transporter.
! Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could
be damaged.
! Do not use the towing eye for recovery,
as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! Drive slowly and smoothly when towing.
Excessive tractive power could otherwise
damage the vehicles.
! Do not tow with sling-type equipment.
This could damage the vehicle.
! When towing vehicles with KEYLESS-GO,
use the key instead of the Start/Stop
button. Otherwise, the automatic
transmission may shift to position P when
the driver's or front-passenger door are
opened, which could lead to damage to the
transmission.
! Vehicles with differential locks: make
sure that the differential locks are in
automatic mode. When towing, the
differential locks must not be switched on
by hand. This could otherwise damage the
transmission.
! Vehicles with automatic transmission
must not be started by tow-starting. This
could otherwise damage the transmission.
! Vehicles with 4MATIC must not be towed
with the front or rear axle raised. This could
otherwise damage the transmission.
If the vehicle has suffered transmission
damage, have it carried away on a transporter
or trailer.
The automatic transmission must be in
position N when the vehicle is being towed.
Make sure that the battery is connected and
charged. You will otherwise not be able to:
R turn the SmartKey to position 2 in the
ignition lock.
R shift the automatic transmission to
position N.
i Switch off the automatic locking feature
before the vehicle is towed ( Y page 79).
Otherwise, you could lock yourself out of
the vehicle when pushing or towing the
vehicle.
Installing/removing the towing eye
Installing the towing eye
Vehicles with a trailer tow hitch: if possible
secure the towing device on the trailer tow
hitch ( Y page 209).
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