
X
To unlock the vehicle: touch the inner sur-
face of the door handle.
X To lock the vehicle: touch sensor surface :
or ;.
Make sure that you do not touch the inner
surface of the door handle.
X Convenience closing feature: touch
recessed sensor surface ;for an extended
period.
For further information on the convenience clos-
ing feature (Y page 94).
If you pull on the handle of the tailgate, only the
luggage compartment of the vehicle is
unlocked.
Deactivating and activating If you do not intend to use a key for an extended
period of time, you can deactivate the KEYLESS-
GO function of the key. The key will then use very little power, thereby conserving battery power.
For the purposes of activation or deactivation,
the vehicle does not have to be nearby.
X To deactivate: press the&button on the
key twice in rapid succession.
The battery check lamp of the key flashes
twice briefly and lights up once, then KEY-
LESS-GO is deactivated (Y page 81).
X To activate: press any button on the key.
or
X Insert the key into the ignition lock.
KEYLESS-GO and all of its associated features
are available again. KEYLESS-GO start function
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a key in
the vehicle (Y page 148). Changing the settings of the locking
system
You can change the settings of the locking sys-
tem. This means that only the driver's door and
the fuel filler flap are unlocked when the vehicle is unlocked. This is useful if you frequently travel
alone. X
To change the setting: press and hold down
the % and& buttons simultaneously
for about six seconds until the battery indica-
tor lamp flashes twice (Y page 81).
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the & or% button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock: press the%button once.
X To unlock centrally: press the%button
twice.
X To lock centrally: press the&button.
The KEYLESS-GO function is changed as fol-
lows:
X To unlock the driver's door: touch the inner
surface of the door handle on the driver's
door.
X To unlock centrally: touch the inner surface
of the door handle on the front-passenger
door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles
(Y page 79).
X To restore the factory settings: press and
hold down the %and& buttons simul-
taneously for approximately six seconds until the battery check lamp flashes twice
(Y page 81). Emergency key element
General notes If the vehicle can no longer be locked or
unlocked with the key or with KEYLESS-GO, use
the emergency key element.
If you use the emergency key element to unlock
and open the driver's door, the anti-theft alarm
system will be triggered. Switch off the alarm
(Y page 75).
If you unlock the vehicle using the emergency
key element, the fuel filler flap will not be
unlocked automatically.
X To unlock the fuel filler flap: insert the key
into the ignition lock. 80
KeyOpening and closing 

Problem
Possible causes/consequences and
M
MSolutions The engine cannot be
started using the key. the on-board voltage is too low.
X Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary (Y page 339).
or
X Jump-start the vehicle (Y page 341).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The key is in
the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The key battery is discharged or nearly discharged.
X Check the key battery (Y page 81) and replace if necessary
(Y page 81).
If this does not work: X Start your vehicle with the key in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the key in the ignition lock. You have lost a key. X
Have the key deactivated at a qualified specialist workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. You have lost the emer-
gency key element. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle, they can:
R open doors and endanger other persons or
road users
R climb out and be injured by the traffic
R operate vehicle equipment and, for exam-
ple, trap themselves. Children could also set the vehicle in motion,
for example by:
R releasing the parking brake
R shifting the automatic transmission out of
park position P
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children unattended in the vehicle. Always
keep the key out of reach of children.
United Kingdom only: 84
DoorsOpening and closing 

Folding the exterior mirrors in/out elec-
trically X
Turn the key to position 1or 2in the ignition
lock (Y page 146).
X Briefly press button :.
Both exterior mirrors fold in or out.
i Make sure that the exterior mirrors are
always folded out fully while driving. They
could otherwise vibrate.
i If you are driving faster than 47 km/h, you
can no longer fold in the exterior mirrors.
Resetting the exterior mirrors If the battery has been disconnected or com-
pletely discharged, the exterior mirrors must be
reset. The exterior mirrors will otherwise not
fold in when you select the "Fold in mirrors whenlocking" function in the on-board computer
(Y page 249).
X Turn the key to position 1in the ignition lock
(Y page 146).
X Briefly press button :.
Folding the exterior mirrors in/out
automatically If the "Fold in mirrors when locking" function is
activated in the on-board computer
(Y page 249):
R the exterior mirrors fold in automatically as
soon as you lock the vehicle from the outside
R the exterior mirrors fold out again automati-
cally as soon as you unlock the vehicle and
then open the driver's or front-passenger
door Exterior mirror pushed out of position If an exterior mirror has been pushed out of
position (forwards or backwards), proceed as
follows:
X Vehicles without electrically folding exte-
rior mirrors: manually move the exterior mir-
ror into the correct position.
X Vehicles with electrically folding exterior
mirrors: press and hold button for mirror
folding :until you hear a click and the mirror
engages audibly in position.
The mirror housing is engaged again and you can adjust the exterior mirrors as usual
(Y page 111). Automatic anti-dazzle mirrors
G
WARNING
Electrolyte may escape if the glass of an auto- matic anti-dazzle mirror breaks. Electrolyte is
harmful and causes irritation. It must not
come into contact with your skin, eyes, res-
piratory organs or clothing or be swallowed.
There is a risk of injury.
If you come into contact with electrolyte,
observe the following:
R immediately rinse off electrolyte from your
skin with water.
R immediately and thoroughly rinse electro-
lyte out of eyes using clean water.
R if electrolyte is swallowed, immediately
rinse out your mouth thoroughly. Do not
induce vomiting.
R if electrolyte comes into contact with skin
or eyes or is swallowed, seek medical atten-
tion immediately.
R immediately change out of clothing that has
been in contact with electrolyte.
R if an allergic reaction occurs, seek medical
attention immediately. 112
MirrorsSeats, steering wheel and
mirrors 

Auxiliary heating
Important safety notes G
DANGER
If the exhaust pipe is blocked or sufficient
ventilation is not possible, toxic exhaust
fumes can enter the vehicle, especially car-
bon monoxide. This is the case, e.g. in
enclosed spaces, or if the vehicle is stuck in
snow. There is a risk of fatal injuries.
You should switch off the auxiliary heating in
enclosed spaces which do not have an extrac- tion system, e.g. a garage. If the vehicle is
stuck in snow and you must leave the auxiliary
heating running, keep the exhaust pipe and
the area around the vehicle clear of snow. To guarantee a sufficient supply of fresh air, open
a window on the side of the vehicle away from the wind. G
WARNING
When the auxiliary heating is switched on,
parts of the vehicle can become very hot.
Flammable materials such as leaves, grass or twigs may ignite if they come into contact
with:
R hot parts of the exhaust system
R the exhaust gas itself
There is a risk of fire.
When the auxiliary heating is switched on,
make sure that:
R no flammable materials come into contact
with hot vehicle components
R the exhaust gas can escape from the
exhaust pipe unhindered
R the exhaust gas does not come into contact
with flammable materials.
The auxiliary heating is fitted under the front
wing on the left-hand side of the vehicle. The
emissions outlet is found behind the left front
wheel.
! Operating the auxiliary heating/ventilation
draws on the vehicle battery. After you have
heated or ventilated the vehicle a maximum of two times, drive for a longer distance. Switch the auxiliary heating on regularly once a
month for about ten minutes.
The auxiliary heating heats the air in the vehicle
interior to the set temperature. This occurs with- out using the heat of the running engine. The
auxiliary heating is operated directly using the
vehicle's fuel. For this reason, the tank content
must be at least at reserve fuel level to ensure
that the auxiliary heating functions.
The auxiliary heating or auxiliary ventilation
automatically adjusts to changes in tempera-
ture and weather conditions. For this reason,
the auxiliary heating could switch from ventila-
tion mode to heating mode or from heating
mode to ventilation mode.
The auxiliary heating switches off when the
engine is switched off. The auxiliary ventilation
switches off when you turn the key to position 2
(Y page 146).
The auxiliary heating switches off automatically after 50 minute s.This time limit can be altered.
To do this, visit a qualified specialist workshop.
You cannot use the auxiliary ventilation to cool
the vehicle interior to a temperature lower than
the outside temperature.
Before switching on X
Turn the key to position 2in the ignition lock
(Y page 146).
X Set the desired temperature.
The auxiliary heating/ventilation can be activa-
ted even when climate control is set to manual.
Optimum comfort can be attained when the sys-
tem is set to automatic mode. Set the temper-
ature to 22 †.
The auxiliary heating or auxiliary ventilation can
be switched on/off using the button on the
centre console or the remote control.
The on-board computer can be used to specify
up to three departure times, one of which may
be preselected (Y page 247).138
Operating the climate control systemClimate control 

Display messages
Possible causes/consequences and
M
MSolutions Wiper malfunction‐
Wiper malfunction‐
ing ing The windscreen wipers are defective.
X Consult a qualified specialist workshop. Hazard warning
Hazard warning
lamps malfunction‐ lamps malfunction‐
ing ing The hazard warning lamps are faulty.
X Consult a qualified specialist workshop. Key
Display messages
Possible causes/consequences and
M
MSolutions Â
Key Key
does
does not
notbelong
belong
to vehicle
to vehicle You have put the wrong key in the ignition lock.
X Use the correct key. Â
Replace key Replace key The key needs to be replaced.
X Consult a qualified specialist workshop. Â
Change Change
key
keybatteries
batteries The key battery is discharged.
X Change the battery (Y page 81).Â
Key not detected Key not detected
(white display message) The key is currently undetected.
X Change the location of the key in the vehicle.
If the key still cannot be detected:
X Operate the vehicle with the key in the ignition lock if necessary. Â
Key not detected Key not detected
(red display message) The key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle cen-
trally or start the engine.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 167).
X Locate the key. Display
messages
285On-board computer and displays Z 

Towing the vehicle with both axles on
the ground
The automatic transmission automatically shifts to position Pwhen you open the driver's or front-
passenger door or when you remove the key
from the ignition lock.
In order to ensure that the automatic transmis-
sion stays in position Nwhen towing away the
vehicle, you must observe the following points:
X Make sure that the vehicle is stationary.
X Turn the key to position 2in the ignition lock.
X Depress the brake pedal and keep it
depressed.
X Shift the automatic transmission to position
N.
X Leave the key in position 2in the ignition lock.
X Release the brake pedal.
X Release the electric parking brake.
X Switch on the hazard warning lamps
(Y page 117).
In order to signal a change of direction when
towing the vehicle with the hazard warning
lamps switched on, use the combination switch
as usual. In this case, only the turn signals for
the desired direction flash. When you reset the
combination switch, the hazard warning lamps
start flashing again. Transporting the vehicle
4MATIC vehicles/vehicles with auto-
matic transmission !
When the vehicle is loaded for transport, the
front and rear axles must be stationary and on
the same transportation vehicle. Positioning
over the connection point of the transport vehicle is not permitted. The drive train may
otherwise be damaged.
All vehicles !
You may only secure the vehicle by the
wheels, not by parts of the vehicle such as
axle or steering components. Otherwise, the
vehicle could be damaged.
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transportation.
X Turn the key to position 2in the ignition lock.
X Shift the automatic transmission to position
N.
As soon as the vehicle is loaded:
X Prevent the vehicle from rolling away by
applying the electric parking brake.
X Shift the automatic transmission to position
P.
X Turn the key to position 0in the ignition lock
and remove it.
X Secure the vehicle. Information for 4MATIC vehicles
! Vehicles with 4MATIC must not be towed
with the front or rear axle raised; otherwise,
the transmission may be damaged.
Vehicles with 4MATIC may either be towed away
with both axles on the ground or be loaded up
and transported.
If the vehicle has transmission damage or dam- age to the front or rear axle, have it transportedon a transporter or trailer.
In the event of damage to the electrical sys-
tem: if the battery is defective, the automatic
transmission will be locked in position P. To shift
the automatic transmission to position N, you
must provide power to the vehicle's on-board
electrical system in the same way as when jump- starting (Y page 341).
Have the vehicle transported on a transporter or trailer. Towing away and tow-starting
345Breakdown assistance Z