key MERCEDES-BENZ C-Class 2011 W204 Owner's Guide

SmartKey battery
Important safety notes
It is advisable to have batteries replaced at a
qualified specialist workshop, e.g. at an
authorized Mercedes-Benz Center.
GWarning!
Batteries are toxic and contain caustic
substances. For this reason, keep batteries
out of the reach of children.
If a battery has been swallowed, visit a doctor
immediately.
GWarning
SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Check with
your local government's disposal guidelines.
California residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Checking the battery
XPress the & or % button.
The SmartKey battery is working properly if
battery charge indicator lamp : lights up
briefly.
If battery charge indicator lamp : does not
light up briefly during the test, the SmartKey
battery is discharged.
XReplace the SmartKey battery
( Y page 74).i
You can obtain a SmartKey battery at any
authorized Mercedes-Benz Center.
i If the SmartKey battery is checked within
signal range of the vehicle, pressing the
& or % button results in the vehicle
being locked or unlocked respectively.
Changing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the
SmartKey ( Y page 73).XPress mechanical key ; into the opening
in the SmartKey in the direction of the
arrow until battery tray cover : opens. Do
not hold the cover closed while doing so.XRemove the cover of the battery tray.XRepeatedly tap the SmartKey against your
palm until battery = falls out.XInsert the new battery with the positive
pole facing upwards. Use a lint-free cloth to
do so.74SmartKeyOpening and closing
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XInsert the front tabs of the battery tray's
cover first and then press to close it.XCheck the function of all SmartKey buttons
on the vehicle.SmartKey75Opening and closingBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 75Z

Problems with the SmartKeyProblemPossible causes/consequences and M SolutionsYou cannot lock/
unlock the vehicle
using the SmartKey.The SmartKey battery is discharged or nearly discharged.XPoint the tip of the SmartKey at the driver's door handle from a
distance of approximately 1.5 ft (50 cm) and try to unlock or
lock the vehicle again.
If this does not work:
XLock or unlock the vehicle using the mechanical key
( Y page 73).XCheck the key battery and replace it if necessary ( Y page 74).The SmartKey is faulty.XLock the vehicle as described in the "Locking the vehicle
(mechanical key)" section ( Y page 79) or unlock it using the
mechanical key ( Y page 73).XHave the SmartKey checked at a qualified specialist workshop.You can no longer
lock/unlock the
vehicle using KEYLESS-
GO.KEYLESS-GO is in standby mode because the vehicle has not been
unlocked for an extended period.XPull the door handle and then turn the SmartKey to position 2
in the ignition lock.There is a malfunction with KEYLESS-GO.XLock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the %/& button.XHave the SmartKey checked at a qualified specialist workshop.There is interference from a powerful source of radio waves.XLock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the %/& button.You have lost a
SmartKey.XHave the SmartKey canceled at an authorized Mercedes-Benz
Center.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.XIf necessary, have the locks changed as well.76SmartKeyOpening and closing
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ProblemPossible causes/consequences and M SolutionsThe engine cannot be
started using the
SmartKey.The on-board voltage is too low.XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary
( Y page 259).
or
XJump-start the vehicle ( Y page 262).
or
XConsult a qualified specialist workshop.The engine cannot be
started using the
SmartKey.The steering lock is mechanically blocked.XRemove the SmartKey and re-insert it into the ignition lock.
While doing this, turn the steering wheel in both directions.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 starter switch. Always
take the SmartKey with you and lock the
vehicle. Do not leave children unattended in
the vehicle, even if they are secured in a child
restraint system, 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. The children
could
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
starter switch or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the child could be burned by these
parts.GWarning!
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
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Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
Rstrong braking maneuvers
Rsudden changes of direction
Ran accident
Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked, unless the child-
proof locks have been activated (Y page 60).
Only open the door if traffic conditions allow
you to do so.
If the vehicle has previously been locked with
the SmartKey or with KEYLESS-GO, opening
a door from the inside will trigger the anti-
theft alarm system. Switch off the alarm
(Y page 67).
XFront door: pull door handle ;.
If the door is locked, locking knob : pops
up. The door is unlocked and can be
opened.
XRear door: pull up locking knob : on the
respective rear door.
The rear door is unlocked and can be
opened.
Centrally locking and unlocking the
vehicle from the inside
The locking or unlocking buttons of the
central locking do not lock or unlock the fuel
filler flap.
iYou cannot unlock the vehicle centrally
from the inside if the vehicle has been
locked with the SmartKey or KEYLESS-GO.
iIt is only possible to lock the vehicle
centrally if the front-passenger door is
closed.
XTo unlock: press button :.XTo lock: press button ;.
You can open a locked front door from inside
the vehicle. Only open the door if traffic
conditions allow you to do so.
If the vehicle has previously been locked with
the central locking button:
Rand the KEYLESS-GO key is restored to the
factory settings, the entire vehicle is
unlocked if a front door is opened from
inside the vehicle.
Rand the KEYLESS-GO key is set to individual
settings, only the front door which is
opened from inside the vehicle is unlocked.
Automatic locking
iThe 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
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lock yourself out if the vehicle is being
pushed, towed, or located on a test rig.
XTo deactivate: press and hold button :
for about five seconds until a tone sounds.
XTo activate: press and hold button ; for
about five seconds until a tone sounds.
iWhen you push either of the two buttons
and an audible warning signal does not
sound, the relevant setting has already
been selected.
On vehicles with a luxury multifunction
steering wheel, you can also activate and
deactivate the automatic locking using the
on-board computer (Y page 181).
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
SmartKey (Y page 73).
XInsert the mechanical key into the lock of
the driver's door as far as it will go.
XTurn the mechanical key counter-clockwise
to position 1.
The door is unlocked.
XTurn the mechanical key back and remove
it.
Locking the vehicle (mechanical key)
Emergency locking
If the vehicle can no longer be locked
centrally with the SmartKey or KEYLESS-GO:
XOpen the driver's door.XClose the front-passenger door, the rear
doors and the trunk lid.
XPress the locking button (Y page 78).XMake sure that the locking knobs on the
doors are still visible. Press down the
locking knobs by hand, if necessary.
XClose the driver's door.XTake the mechanical key out of the
SmartKey (Y page 73).
XInsert the mechanical key into the lock of
the driver's door as far as it will go.
XTurn the mechanical key clockwise as far
as it will go to position 1.
XTurn the mechanical key back and remove
it.
XMake sure that the doors and the trunk lid
are locked.
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iIf 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 accidentGWarning
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.
For the trunk lid to be opened fully, there must
be a minimum clearance from floor to ceiling
of 5.90 ft (1.80 m).
The trunk lid can be:
R opened and closed manually from outside
R opened automatically from outside
Opening and closing manually
Opening
You can only open the trunk lid after
unlocking it first.
You can only unlock the trunk lid when the
vehicle is stationary.
XPress the % button on the SmartKey.80TrunkOpening and closing
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XPull handle :.XRaise the trunk lid.
Closing
GWarning
To prevent possible personal injury, always
keep hands and fingers away from the trunk
opening when closing the trunk lid. Be
especially careful when small children are
around.
XPull the trunk lid down using recess :.XLock the vehicle if necessary with
the & button on the SmartKey or with
KEYLESS-GO ( Y page 71).
Automatic opening and closing from
the outside
Important safety guidelines
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.
For the trunk lid to be opened fully, there must
be a minimum clearance from floor to ceiling
of 5.90 ft (1.80 m).
Opening
You can open the trunk lid automatically
using the SmartKey or the handle in the trunk
lid.
XPress and hold the F button on the
SmartKey until the trunk lid opens.
or
XWhen the trunk is unlocked, pull on the
trunk lid handle and let it go again
immediately.
Closing
i If you leave a KEYLESS-GO key in the
trunk, the trunk lid will not lock.
Opening automatically from the
inside
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.
You can open the tailgate from the driver's
seat when the vehicle is stationary.
XTo open: press the upper section of remote
operating switch : for the trunk lid until
the trunk lid opens.Trunk81Opening and closingBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 81Z

Locking the trunk separately
You can lock the trunk separately. If you then
unlock the vehicle centrally, the trunk
remains locked and cannot be opened.
XClose the trunk lid.XTake the mechanical key out of the
SmartKey (Y page 73).
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.
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 73).
XInsert the mechanical key into the trunk lid
lock as far as the stop.
XTurn the mechanical key counter-clockwise
as far as it will go to position 2.
The trunk is unlocked.
XTurn the mechanical key back to basic
position 1 and remove it.
Emergency trunk release
You can open the trunk lid from inside the
vehicle with the emergency release button.
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:
RThe button flashes for 30 minutes after the
trunk lid is opened.
RThe 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.
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Side windows
Important safety notes
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. Always
take the SmartKey with you and lock the
vehicle. Do not leave children unattended in
the vehicle, even if they are secured in a child
restraint system, 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. The children
could
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
starter switch or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the child could be burned by 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!
When opening or closing the door windows,
make sure there is no danger of anyone being
harmed by the opening/closing procedure.
The door windows are equipped with the
automatic operation and anti-entrapment
features. If during automatic operation a 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 and held. See the section
about the side windows for details.
The closing of the 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.
If a door window encounters an obstruction
that blocks its path in a circumstance where
you are closing the door windows by pressing
and holding button & on the SmartKey or
by pressing and holding the sensor surface
(vehicles with KEYLESS-GO) on an outside
door handle, the anti-entrapment feature will
not operate.
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.
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