
ProblemPossible causes/consequences and M SolutionsThe engine cannot be
started using the
SmartKey.The on-board voltage is too low.XRemove the SmartKey and re-insert it into the ignition lock.XStart the engine within 30 seconds of inserting the SmartKey in
the ignition lock.XRepeat if necessary.
If the engine does not start after several attempts:
XCheck the starter battery and charge it if necessary .
or
XJump-start the vehicle .
or
XConsult a qualified specialist workshop.The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.A door is open. Therefore, the SmartKey cannot be detected as
easily.XClose the door and try to start the vehicle again.There is interference from a powerful source of radio waves.XStart your vehicle with the SmartKey in the ignition lock.Doors
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
Do not carry heavy or hard objects in the
passenger compartment unless they are
firmly secured in place.
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
Doors81Opening and closingZ

Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked.
Open the door only when the traffic
conditions permit.
If the vehicle has been opened with the
SmartKey or KEYLESS-GO key, opening from
inside triggers the anti-theft alarm system.
Switch off the alarm ( Y page 70).XPull door handle ;.
If the door is locked, locking knob : pops
up. The door is unlocked and can be
opened.
i When a door is opened, the side window
on that side opens slightly. When the door
is closed, the side window closes again.
! The side windows will not open/close if
the battery is discharged or if the side
windows have iced up. It will then not be
possible to close the door. Do not attempt
to force the door closed. You could
otherwise damage the door or the side
window.
Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside. This feature may be useful if,
for example, you wish to unlock the front-
passenger door from the inside or lock the
vehicle before you pull away.
The locking or unlocking buttons of the
central locking do not lock or unlock the fuel
filler flap.XTo lock: press button ;.
The vehicle locks when all front-passenger
doors are closed.XTo unlock: press button :.
You can open a locked door from inside the
vehicle. Open the door only when the traffic
conditions permit.
If the vehicle has been locked with the central
locking button:
R and the SmartKey is restored to the factory
settings, the entire vehicle is unlocked if a
door is opened from inside the vehicle.
R and the SmartKey is set to individual
settings, only the 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 does
not unlock if you use the unlocking button of
the central locking.
Automatic locking feature
The vehicle locks automatically when the
ignition is switched on and the wheels of the
vehicle are moving at a speed of more than
9 mph (15 km/h). You may therefore lock
yourself out if the vehicle is being pushed,
towed, or located on a test rig.
You can switch off the automatic locking
function via COMAND .
82DoorsOpening and closing

Power closing feature
The power closing feature pulls the doors and
trunk lid into their locks automatically even if
they are only partly closed.GWARNING
To prevent possible personal injury, always
keep hands and fingers away from the door or
trunk opening when closing a door or the
trunk lid. Be especially careful when small
children are around.
If danger threatens, pull the inside or outside
door handle, or pull the trunk lid handle.
To prevent personal injury, never activate the
closing assist mechanism by tampering with
the door or trunk lid latch.
GWARNING
Only drive with the doors closed. Otherwise,
one or more of the doors could open while the
vehicle is in motion, putting you and/or
others at risk.
GWARNING
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
XPower closing feature (doors): push the
door past the first detent position of the
lock.
The power closing feature will pull the door
fully closed.XPower closing feature (trunk lid): lightly
push the trunk lid closed.
The power closing feature will pull the trunk
lid fully closed.
Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked
centrally with the SmartKey or KEYLESS-GO:
XTake the mechanical key out of the key
( Y page 77).XInsert the mechanical key into the lock of
the driver's door as far as it will go.XFirmly turn the mechanical key counter-
clockwise as far as it will go to position
1 and hold it in this position.XPull the door handle quickly.
The locking knob pops up.
The door is unlocked.XTurn the mechanical key back and remove
it.XPull the door handle again.XReplace the mechanical key in the
SmartKey.
Locking the vehicle
If the vehicle can no longer be locked
centrally with the SmartKey or KEYLESS-GO:
If the SmartKey is faulty, you can lock the
doors and the trunk by taking the following
steps. If the central locking in the vehicle is
malfunctioning, you cannot lock the trunk.
XOpen the front-passenger door.XClose the driver's door and the trunk lid.XPress down the locking knob of the driver's
door inside the vehicle.XPress down the locking knob of the open
front-passenger door.
i Make sure that you have the SmartKey on
your person and that it has not been left in
the vehicle.
Doors83Opening and closingZ

XClose the front-passenger door.XMake sure that the doors and the trunk 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 activated.
Trunk
Important safety notes
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.
GWARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
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
GWARNING
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
You can limit the opening angle of the trunk
lid. This could be useful, for example, if there
is insufficient space above the trunk lid. You
can switch the Trunk Opening-height
Restriction function on or off via COMAND
( Y page 239).
To open the trunk lid completely, a minimum
clearance of 5.90 ft (1.80 m) above the
ground is necessary.
The trunk lid can be:
R opened and closed manually from outside
R opened and closed automatically from
outside
R opened and closed automatically from
inside
R locked separately
R unlocked using the mechanical key
R opened using the emergency release
button inside the trunk
84TrunkOpening and closing

XInsert the mechanical key into the trunk lid
lock as far as the stop.XTurn the mechanical key clockwise from
position 1 to position 2.XRemove the mechanical key.XReplace the mechanical key in the
SmartKey.
Unlocking the trunk (mechanical key)
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
If the trunk can no longer be unlocked with
the SmartKey or KEYLESS-GO:
XTake the mechanical key out of the
SmartKey ( Y page 77).XInsert the mechanical key into trunk lid
lock : as far as the stop.XTurn the mechanical key counter-clockwise
as far as possible.
The trunk is unlocked.XTurn the mechanical key back and remove
it.XReplace the mechanical key in the
SmartKey.
Trunk emergency release
You can open the trunk lid from inside the
vehicle with the emergency release button.
XBriefly press emergency release
button :.
The trunk lid unlocks and opens.
The trunk lid can be unlocked and opened
with the trunk lid emergency release when
the vehicle is stationary or while driving.
Trunk lid emergency release light:
R The button flashes for 30 minutes after the
trunk lid is opened.
R The button flashes for 60 minutes after the
trunk lid is closed.
The trunk lid emergency release does not
open the trunk lid if the battery is
disconnected or discharged.
Trunk87Opening and closingZ

Side windows
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.
GWARNING
Do not carry heavy or hard objects in the
passenger compartment unless they are
firmly secured in place.
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
GWARNING
When opening or closing the door windows,
make sure that there is no danger of anyone
being harmed by the opening/closing
procedure.
The front door windows are equipped with
automatic operation and the anti-entrapment
feature. If in automatic mode a front door
window encounters an obstruction that
blocks its path, the anti-entrapment feature
will stop the door window and open it slightly.
The door windows operate differently when
the switch is pulled. See the "Problems with
door windows" section for details.
The closing of the front door windows can be
immediately halted by releasing the switch or,
if the switch was pulled past the resistance
point and released, by either pressing or
pulling the respective switch.
The closing of the rear side windows can be
immediately halted by releasing the switch.
Activate the override switch when children
are riding in the back seats of the vehicle. The
children may otherwise injure themselves,
e.g. by becoming trapped in the door window
opening.
GWARNING
Do not keep any part of your body up against
the window pane when opening a window. The
downward motion of the pane may pull that
part of your body down between the window
pane and the door frame and trap it there. If
there is a risk of entrapment, release the
switch and pull it to close the window.
88Side windowsOpening and closing

closing procedure, press and hold the
& button.
Vehicles with KEYLESS-GO:
R Release the sensor surface on the outside
door handle to stop the closing procedure.
R Immediately pull on the same outside door
handle and hold firmly. The door windows
and the sliding sunroof will open for as long
as the door handle is held but the door is
not opened.
Using the SmartKey
i The SmartKey must be close to the
driver's door handle.
XPoint the tip of the SmartKey at the driver's
door handle.XLock the vehicle by pressing the &
button.XPress and hold the & button until the
side windows and the sliding sunroof are
fully closed.XMake sure that all the side windows and the
sliding sunroof are closed.XTo interrupt the convenience closing:
release the & button.
Using KEYLESS-GO
The KEYLESS-GO key must be outside the
vehicle but must not be further than 3 ft (1 m)
from a door.
XClose all the doors.XTouch sensor surface : on the door
handle until the side windows and the
sliding sunroof are fully closed.
i Make sure you only touch sensor
surface :.
XMake sure that all the side windows and the
sliding sunroof are closed.XTo interrupt convenience closing:
release sensor surface : on the door
handle.
Resetting the side windows
You must reset each side window if:
R the front side window does not close
automatically.
R the side window reopens slightly after
having been closed manually.
XClose all the doors.XTurn the SmartKey to position 1 in the
ignition lock.XPull the corresponding switch on the door
control panel until the side window is
completely closed ( Y page 89).XHold the switch for an additional second.
If the side window opens again slightly:
XImmediately pull the corresponding switch
on the door control panel until the side
window is completely closed ( Y page 89).XHold the switch for an additional second.XIf the respective side window remains
closed after the button is released, then it
has been set correctly. If this is not the
case, repeat the previously described
steps.90Side windowsOpening and closing

Problems with the side windows
Problem: a side window cannot be closed
because an object is obstructing the side
window.XRemove the object(s).XClose the side window.
Problem: a side window cannot be closed,
and you cannot see the cause.
GWARNING
Closing the side windows with increased force
or without the anti-entrapment feature could
lead to serious or even fatal injury. Make sure
that nobody can become trapped when
closing the side windows.
If a side window is obstructed during closing
and reopens again slightly:
XImmediately after the window blocks, pull
the corresponding switch again until the
side window has closed.
The side window is closed with increased
force.
If a side window is obstructed again during
closing and reopens again slightly:
XImmediately after the window blocks, pull
the corresponding switch again until the
side window has closed.
The side window is closed without the anti-
entrapment feature.GWARNING
Pulling and holding the switch to close the
window immediately after it had been blocked
two times will cause the window to close
without the anti-entrapment feature for as
long as you hold the switch.
Sliding sunroof
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.
GWARNING
Do not carry heavy or hard objects in the
passenger compartment unless they are
firmly secured in place.
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
Sliding sunroof91Opening and closingZ