2012 MERCEDES-BENZ C-Class COUPE key battery

X To unlock the vehicle: touch the inner
surface of the door handle.XTo lock the vehicle: touch sensor
surface :.XConvenience closing feature: touch
recessed sensor surface ; for an
extended period ( Y page 83).
If you pull on the handle of the trunk lid, only
the trunk of the vehicle is unlocked.
Changing the settings of the locking
system
You can change the setting of the locking
system in such a way that only the driver's
door and the fuel filler flap are unlocked. This
is useful if you frequently travel on your own.
XTo change the setting: press and hold
down the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
( Y page 72) flashes twice.
i
If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the & or % button
locks or unlocks the vehicle.
The SmartKey now functions as follows:
XTo unlock the driver's door: press the
% button once.XTo unlock centrally: press the %
button twice.XTo lock centrally: press the & button.
The KEYLESS-GO function is changed as
follows:
XTo unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.XTo unlock centrally: touch the inner
surface of the front-passenger door handle.XTo lock centrally: touch the outer sensor
surface on one of the door handles.Restoring the factory settingsXPress the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice.
Mechanical key
General notes
If the vehicle can no longer be locked or
unlocked with the SmartKey, use the
mechanical key.
If you use the mechanical key to unlock and
open the driver's door or the trunk lid, the
anti-theft alarm system will be triggered
( Y page 64).
There are several ways to turn off the alarm:
XTo turn the alarm off with the
SmartKey: press the % or & button
on the SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XTo deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the
ignition lock. The SmartKey must be in the
vehicle.
or
XLock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked
automatically.
XTo unlock the fuel filler flap: insert the
SmartKey in the ignition lock.SmartKey71Opening/closingZ

Removing the mechanical keyXPush release catch : in the direction of
the arrow and at the same time, remove
mechanical key ; from the SmartKey.
SmartKey battery
Important safety notes
Have the batteries changed at a qualified
specialist workshop.
GWARNING
Batteries contain toxic substances.
Swallowing batteries can lead to serious
health issues or death.
Keep batteries out of the reach of children.
Seek medical attention immediately if a
battery is swallowed.
GWARNING
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Observe
government disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Checking the batteryXPress the & or % button.
The battery is working properly if battery
check lamp : lights up briefly
If battery check lamp : does not light up
briefly during the test, the battery is
discharged.
XChanging the battery ( Y page 72)
i
You can obtain the battery at a qualified
specialist workshop.
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the & or % button locks or
unlocks the vehicle.
Changing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the
SmartKey ( Y page 71).XPress mechanical key ; into the opening
in the SmartKey in the direction of the72SmartKeyOpening/closing

arrow until battery tray cover : opens.
When doing so, do not hold cover : shut.XRemove battery tray cover :.XRepeatedly tap the SmartKey against your
palm until battery = falls out.XInsert the new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so.XMake sure that the surface of the battery is
free from lint, grease and all other forms of
contamination.XInsert the front tabs of battery tray
cover : and then press to close it.XInsert the mechanical key into the
SmartKey.XCheck the function of all SmartKey buttons
on the vehicle.SmartKey73Opening/closingZ

Problems with the SmartKeyProblemPossible causes/consequences and M SolutionsYou cannot lock or
unlock the vehicle
using the SmartKey.The SmartKey battery is discharged or nearly discharged.XTry again to lock/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.
If this does not work:
XCheck the SmartKey battery ( Y page 72) and replace it if
necessary ( Y page 72).XLock ( Y page 77) or unlock ( Y page 77) the vehicle using
the mechanical key.The SmartKey is faulty.XLock ( Y page 77) or unlock ( Y page 77) the vehicle using
the mechanical key.XHave the SmartKey checked at a qualified specialist workshop.You can no longer lock
or unlock the vehicle
using KEYLESS-GO.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.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 KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
XCheck the SmartKey battery ( Y page 72) and replace it if
necessary ( Y page 72).XLock ( Y page 77) or unlock ( Y page 77) the vehicle using
the mechanical key.You have lost a
SmartKey.XHave the SmartKey deactivated at a qualified specialist
workshop.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.74SmartKeyOpening/closing

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 284).
or
XJump-start the vehicle ( Y page 287).
or
XConsult a qualified specialist workshop.The engine cannot be
started using the
SmartKey.The steering lock is mechanically blocked.XRemove the SmartKey and reinsert 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 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.
Doors75Opening/closingZ

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 emergency release button : flashes for
30 minutes after the trunk lid is opened.
R emergency release 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.
Side windows
Important safety notes
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 more 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 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 windows by pressing and
holding & button on the SmartKey or by
pressing and holding the lock button (vehicles
with KEYLESS-GO) on an outside door handle,
the anti-entrapment feature will not operate.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.
Opening and closing the side
windows
:Left;Right
The switches for all side windows are located
on the driver's door. There is also a switch for
the front-passenger side window on the front-
passenger door.
The switches on the driver's door take
precedence.
Side windows81Opening/closingZ

:To raise the backrest contour;To soften the backrest contour=To lower the backrest contour?To harden the backrest contour
Switching the seat heating on/off
Switching on/off
GWARNING
Repeatedly setting the seat heating to level
3 may result in excessive seat temperatures.
The health of passengers that have limited
temperature sensitivity or a limited ability to
react to excessively high temperatures may
be affected or they may even suffer burn-like
injuries. Therefore, do not use seat heating
level 3 repeatedly.
The three red indicator lamps in the button
indicate the heating level you have selected.
i If the battery voltage is too low, the seat
heating may switch off.
Driver's and front-passenger seat
The system automatically switches down
from level 3 to level 2 after approximately
eight minutes.
The system automatically switches down
from level 2 to level 1 after approximately ten
minutes.
The system automatically switches off
approximately 20 minutes after it is set to
level 1.XMake sure that the SmartKey is in position
1 or 2 in the ignition lock.XTo switch on: press button : repeatedly
until the desired heating level is set.XTo switch off: press button : repeatedly
until all the indicator lamps go out.
Problems with the seat heating
The seat heating has switched off
prematurely or cannot be switched on. The
vehicle's electrical system voltage is too low
because too many electrical consumers are
switched on.
XSwitch off electrical consumers which you
do not need, such as the rear window
defroster or interior lighting.
Switching the seat ventilation on/off
Switching on/off
The three blue indicator lamps in the buttons
indicate the ventilation level you have
selected.
i If the battery voltage is too low, the seat
ventilation may switch off.
92SeatsSeats, steering wheel and mirrors

Setting the exterior mirrors
This function is only available in vehicles for
Canada.
If the battery has been disconnected or
completely discharged, the exterior mirrors
must be reset. The exterior mirrors will
otherwise not fold in when you select the
"Fold in mirrors when locking" function in the
on-board computer ( Y page 197).
XMake sure that the SmartKey is in
position 1 in the ignition lock.XBriefly press button :.
Folding the exterior mirrors in or out
automatically
This function is only available in vehicles for
Canada.
If the "Fold in mirrors when locking" function
is activated in the on-board computer
( Y page 197):
R the exterior mirrors fold in automatically as
soon as you lock the vehicle from the
outside.
R the exterior mirrors fold out again
automatically as soon as you unlock the
vehicle and then open the driver's or front-
passenger door.
i The mirrors do not fold out if they have
been folded in manually.
Exterior mirror out of position
If an exterior mirror has been pushed out of
position, proceed as follows:
XVehicles without electrically folding
exterior mirrors: move the exterior mirror
into the correct position manually.XVehicles with electronically folding
mirrors 3
: press the mirror-folding button( Y page 95) repeatedly until you hear the
mirror engage in position.
The mirror housing is engaged again and
you can adjust the exterior mirrors as usual
( Y page 95).
Automatic anti-glare mirrors
GWARNING
If incident light from headlamps is prevented
from striking the sensor in the rear-view
mirror, for instance, by luggage piled too high
in the vehicle, the mirror's automatic anti-
glare function will not operate.
Incident light could then blind you. This may
distract you from the traffic conditions and,
as a result, you may cause an accident.
The rear-view mirror and the exterior mirror
on the driver's side automatically go into anti-
glare mode if the ignition is switched on and
incident light from headlamps strikes the
sensor in the rear-view mirror.
The mirrors do not go into anti-glare mode if
reverse gear is engaged.
Parking position for the exterior
mirror on the front-passenger side
Setting and storing the parking position
You can position the front-passenger side
exterior mirror in such a way that you can see
the rear wheel on that side as soon as you
engage reverse gear. You can store this
position.
3 Canada only96MirrorsSeats, steering wheel and mirrors