2012 MERCEDES-BENZ C-Class SEDAN ignition

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 298).
or
XJump-start the vehicle ( Y page 301).
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.
Doors77Opening/closingZ

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
Unlocking and opening doors from
inside
You can open a door from inside the vehicle
even if it has been locked. You can only open
the rear doors from inside the vehicle if they
are not secured by the child-proof locks
( Y page 57).
Only open the door when the traffic situation
permits.
If the vehicle was previously locked with the
SmartKey or with KEYLESS-GO, opening the
vehicle from the inside will activate the anti-
theft alarm system. Switch off the alarm
( Y page 67).
XPull door handle ;.
If the door is locked, locking knob : pops
up. The door is unlocked and can be
opened.
Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside.
The central locking/unlocking button does
not lock or unlock the fuel filler flap.
i You cannot unlock the vehicle centrally
from the inside if the vehicle has been
locked with the SmartKey or KEYLESS-GO.
i It is only possible to lock the vehicle
centrally if the front-passenger door is
closed.XTo unlock: press button :.XTo lock: press button ;.
If the front-passenger door is closed, the
vehicle locks.
You can open a front door from inside the
vehicle even if it has been locked. Only open
the door when the traffic situation permits.
If the vehicle has been locked with the central
locking button:
R and the SmartKey is set to its factory
setting, the entire vehicle is unlocked if a
front door is opened from the inside
R and the SmartKey is set to an individual
setting, only the front 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 is not
unlocked when the release button for the
central locking is used.
Automatic locking feature
The vehicle locks automatically when the
ignition is switched on and the wheels of the
78DoorsOpening/closing

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.XInsert the mechanical key into the
SmartKey.
i If you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not armed.
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.
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 automatically from outside
R opened automatically from inside
R locked separately
80TrunkOpening/closing

The switches for all side windows are located
on the driver's door. There is also a switch on
each door for the corresponding side window.
The switches on the driver's door take
precedence.
i The side windows cannot be operated
from the rear when the override feature for
the side windows is activated ( Y page 57).XTurn the SmartKey to position 1 or 2 in the
ignition lock.XTo open: press the corresponding switch.XTo close: pull the corresponding switch.
i
If you press the switch beyond the point
of resistance, an automatic opening/
closing process is started in the
corresponding direction. You can stop
automatic operation by operating the
switch again.
i You can continue to operate the side
windows after you switch off the engine or
remove the SmartKey. This function is
available for up to five minutes or until the
driver's or front-passenger door is opened.
Convenience opening feature
You can ventilate the vehicle before you start
driving. To do this, the key is used to carry out
the following functions simultaneously:
R unlock the vehicle
R open the side windows
R open the sliding sunroof or the panorama
roof with power tilt/sliding panel and the
roller sunblinds
i The convenience opening feature can
only be operated using the SmartKey. The
SmartKey must be close to the driver's
door handle.
XPoint the tip of the SmartKey at the driver's
door handle.XPress and hold the % button until the
side windows and the sliding sunroof or thepanorama roof with power tilt/sliding
panel are in the desired position.
If the roller sunblinds of the panorama roof
with power tilt/sliding panel are closed, the
roller sunblinds are opened first.
XPress and hold the % button again until
the panorama roof with power tilt/sliding
panel is in the desired position.XTo interrupt convenience opening:
release the % button.
Convenience closing
General notes
When you lock the vehicle, you can
simultaneously:
R close the side windows
R close the sliding sunroof or the panorama
roof with power tilt/sliding panel
On vehicles with a panorama roof with power
tilt/sliding panel, you can then close the
roller sunblinds.
GWARNING
When closing the door windows and the
sliding sunroof or panorama roof with power
tilt/sliding panel, make sure that there is no
danger of anyone being harmed by the closing
procedure.
If potential danger exists, proceed as follows:
R Release the & button to stop the closing
procedure. To open, press and hold the
% button. To continue the closing
procedure after making sure that there is
no danger of anyone being harmed by the
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 or panorama roof
84Side windowsOpening/closing

with power tilt/sliding panel 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.XPress and hold the & button until the
side windows and the sliding sunroof or the
panorama roof with power tilt/sliding
panel are fully closed.XMake sure that all the side windows and the
sliding sunroof or panorama roof with
power tilt/sliding panel are closed.
On vehicles with a panorama roof with power
tilt/sliding panel:
XPress and hold the & button again until
the roller sunblinds of the panorama roof
with power tilt/sliding panel close.XTo interrupt convenience closing:
release the & button.
Using KEYLESS-GO
The KEYLESS-GO key must be outside the
vehicle. All the doors must be closed.
XTouch recessed sensor surface : on the
door handle until the side windows and thesliding sunroof or the panorama roof with
power tilt/sliding panel are fully closed.
i Make sure you only touch recessed
sensor surface :.
XMake sure that all the side windows and the
sliding sunroof or panorama roof with
power tilt/sliding panel are closed.
On vehicles with a panorama roof with power
tilt/sliding panel:
XTouch recessed sensor surface : on the
door handle again until the roller sunblinds
of the panorama roof with power tilt/
sliding panel close.XTo interrupt convenience closing:
release recessed sensor surface : on the
door handle.
Resetting the side windows
You must reset each side window if a side
window can no longer be closed fully.
XClose all the doors.XTurn the SmartKey to position 1 or 2 in the
ignition lock.XPull the corresponding switch on the door
control panel until the side window is
completely closed. ( Y page 83)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 83).XHold the switch for an additional second.XIf the corresponding side window remains
closed after the button has been released,
the side window has been reset correctly.
If this is not the case, repeat the steps
above again.Side windows85Opening/closingZ

damaged if water enters the vehicle
interior.
i Resonance noises can occur in addition
to the usual airflow noises when the sliding
sunroof is open. They are caused by minor
pressure fluctuations in the vehicle interior.
Change the position of the sliding sunroof
or open a side window slightly to reduce or
eliminate these noises.
Operating the sliding sunroof
Opening and closing
i You can continue to operate the sliding
sunroof after switching off the engine or
removing the SmartKey from the ignition
lock. This function is available for up to five
minutes or until the driver's or front-
passenger door is opened.
Overhead control panel
:To raise;To open=To close/lowerXTurn the SmartKey to position 1 or 2 in the
ignition lock.XPress or pull the 3 switch in the
corresponding direction.
i If you press the 3 switch beyond the
point of resistance, an automatic opening/
closing process is started in the
corresponding direction. You can stop
automatic operation by operating the
switch again.
When opening and raising the roof,
automatic operation is only available if the
sliding sunroof is in the closed position.
The sun protection cover automatically opens
along with the sliding sunroof. You can open
or close the sun protection cover manually
when the sliding sunroof is raised or closed.
Resetting
Reset the sliding sunroof if it does not move
smoothly.
XTurn the SmartKey to position 2 in the
ignition lock.XRaise the sliding sunroof fully at the rear
( Y page 87).XKeep the 3 switch pressed for another
second.XMake sure that the sliding sunroof can be
fully opened and closed again (Y page 87).XIf this is not the case, repeat the steps
above again.
! If the sliding sunroof still cannot be
opened or closed fully after resetting,
contact a qualified specialist workshop.
Operating the panorama roof with
power tilt/sliding panel
Opening and closing
Overhead control panel
:To raise;To open=To close/lowerSliding sunroof87Opening/closingZ

The panorama roof with power tilt/sliding
panel can only be operated when the roller
sunblind is open.XTurn the SmartKey to position 1 or 2 in the
ignition lock.XPush or pull the 3 switch in the
corresponding direction.
i If you press the 3 switch beyond the
point of resistance, an automatic opening/
closing process is started in the
corresponding direction. You can stop
automatic operation by operating the
switch again.
When raising the roof, automatic operation
is only available if the panorama roof with
power tilt/sliding panel is in the closed
position.
Operating the sunblinds for the
panorama roof with power tilt/sliding
panel
General notes
The roller sunblinds shield the vehicle interior
from sunlight. The two roller sunblinds can
only be opened and closed together when the
panorama roof with power tilt/sliding panel
is closed.
GWARNING
When opening or closing the roller sunblinds,
make sure that no one can be injured.
The roller sunblinds have automatic operation
and an anti-entrapment feature. If the roller
sunblinds are blocked during the closing
procedure, the anti-entrapment feature stops
the roller sunblinds and they open again
slightly.
The opening and closing of the roller
sunblinds can be terminated immediately by
releasing the button. In automatic operation,
press the button briefly in any direction to
stop the roller sunblinds.
Opening and closing
Overhead control panel
:To open;To open=To closeXTurn the SmartKey to position 1 or 2 in the
ignition lock.XPress or pull the 3 switch in the
corresponding direction.
i If you press the 3 switch beyond the
point of resistance, an automatic opening/
closing process is started in the
corresponding direction. You can stop
automatic operation by operating the
switch again.
Resetting the panorama roof with
power tilt/sliding panel and the roller
sunblinds
Reset the panorama roof with power tilt/
sliding panel and the roller sunblinds if the
panorama roof with power tilt/sliding panel
or the roller sunblinds do not move smoothly.
XTurn the SmartKey to position 1 or 2 in the
ignition lock.XPress the 3 switch to the point of
resistance in the direction of arrow ; and
hold it until the panorama roof with power
tilt/sliding panel has opened about 4 in
(10 cm).XPull the 3 switch repeatedly to the point
of resistance in the direction of arrow =88Sliding sunroofOpening/closing

The time period starts over again if, within
these three minutes, you:
R open or close a front door
R insert the SmartKey into the ignition lock
or remove it from the ignition lock
R switch the ignition on or off
If the SmartKey is in position 2 in the
ignition lock, the seats can be adjusted at
any time.
Depending on the equipment, the seat
adjustment buttons are either located on the
side of the seat or on the door control panel.:Head restraint height;Seat cushion angle=Seat height?Seat fore-and-aft adjustmentABackrest angle:Seat cushion angle;Seat height=Seat fore-and-aft adjustment?Backrest anglei You can store the seat settings using the
memory function ( Y page 103).
i AMG vehicles are equipped with a seat
featuring an integrated head restraint and
the head restraint adjustment button is
deactivated. It is therefore not possible to
set the height and angle of the head
restraint.
Adjusting the head restraints
Adjusting the head restraints manually
Adjusting the head restraint height 3
XTo raise:
pull the head restraint up to the
desired position.XTo lower: press release catch : in the
direction of the arrow and push the head
restraint down to the desired position.
Adjusting the angle of the head restraints
3 For vehicles without memory function only.Seats95Seats, steering wheel and mirrorsZ