2012 MERCEDES-BENZ C-Class SEDAN child lock

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 74)
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 73).XPress mechanical key ; into the opening
in the SmartKey in the direction of the74SmartKeyOpening/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 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

Runlocked with the mechanical key
R opened with the emergency release button
Opening and closing manually
Opening
XPress the % button on the SmartKey.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 :.XIf necessary, lock the vehicle with
the & button on the SmartKey(Y page 70) or with KEYLESS-GO
( Y page 71).
i
If a KEYLESS-GO key is detected in the
trunk, the trunk lid cannot be locked and
then opens again.
Opening automatically from outside
Important safety notes
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.
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 the trunk
lid handle and let it go again immediately.
Closing
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)
Trunk81Opening/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 door windows are equipped with
automatic operation and the anti-entrapment
feature. If in automatic mode 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. See the "Problems with
door windows" section 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 windows by pressing and
holding the & 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.
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.
Opening and closing the side
windows
:Front left;Front right=Rear right?Rear leftSide windows83Opening/closingZ

(Y page 101) in such a way that you have
a good view of road and traffic conditions.XVehicles with a memory function: save
the seat, steering wheel and exterior mirror
settings ( Y page 103).
Seats
Important safety notes
GWARNING
In order to avoid possible loss of vehicle
control, all seat, head restraint, steering
wheel and rear view mirror adjustments, as
well as fastening of seat belts, must be done
before setting the vehicle in motion.
GWARNING
Do not adjust the driver's seat while driving.
Adjusting the seat while driving could cause
the driver to lose control of the vehicle.
Never travel in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
the seat belt in a collision. If you slide under
it, the seat belt would apply force at the
abdomen or neck. This could cause serious or
fatal injuries. The seat backrest and seat belts
provide the best restraint when the wearer is
in a position that is as upright as possible and
seat belts are properly positioned on the
body.
GWARNING
Your seat belt must be adjusted so that you
can correctly fasten your seat belt.
Observe the following points:
R adjust the seat backrest until your arms are
slightly angled when holding the steering
wheel.
R adjust the seat to a comfortable seating
position that still allows you to reach the
accelerator/brake pedal safely. The
position should be as far back as possible
with the driver still able to operate the
controls properly.
R adjust the head restraint so that it is as
close to the head as possible and the center
of the head restraint supports the back of
the head at eye level.
R never place hands under the seat or near
any moving parts while a seat is being
adjusted.
Failure to do so could result in an accident
and/or serious personal injury.GWARNING
The electrically adjustable seats can be
operated at any time. Therefore, do not leave
children unattended in the vehicle, 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.
GWARNING
According to accident statistics, children are
safer when properly restrained in the rear
seating positions than in the front seating
position. Thus, we strongly recommend that
children be placed in the rear seats whenever
possible. Regardless of seating position,
children 12 years old and under must be
seated and properly secured in an
appropriately sized infant restraint, toddler
restraint, or booster seat recommended for
the size and weight of the child. For additional
information, see "Children in the vehicle".
A child's risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.
GWARNING
For your protection, drive only with properly
positioned head restraints.
Adjust the head restraint so that it is as close
to the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
Seats93Seats, steering wheel and mirrorsZ

iIf the battery voltage is too low, the seat
ventilation may switch off.XMake sure that the SmartKey is in position
2 in the ignition lock.XTo switch on: press button : repeatedly
until the desired ventilation level is set.
i You can open the side windows and the
sliding sunroof using the "Convenience
opening" feature ( Y page 84). The seat
ventilation of the driver's seat
automatically switches to the highest level.
XTo switch off: press button : repeatedly
until all the indicator lamps go out.
Problems with the seat ventilation
The seat ventilation 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.
Steering wheel
Important safety notes
GWARNING
Do not adjust the steering wheel while driving.
Adjusting the steering wheel while driving, or
driving without the steering wheel adjustment
feature locked could cause the driver to lose
control of the vehicle.
The electrical steering wheel adjustment
feature can be operated at any time.
Therefore, do not leave children unattended
in the vehicle, 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.
Adjusting the steering wheel
manually
:Release lever;To adjust the steering wheel height=To adjust the steering wheel position
(fore-and-aft adjustment)XPush release lever : down completely.
The steering column is unlocked.XAdjust the steering wheel to the desired
position.XPush release lever : up completely.
The steering column is locked.XCheck if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction.Steering wheel99Seats, steering wheel and mirrorsZ