keyless MERCEDES-BENZ C-Class SEDAN 2012 W204 User Guide

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 74) and replace it if
necessary ( Y page 74).XLock ( Y page 79) or unlock ( Y page 79) the vehicle using
the mechanical key.The SmartKey is faulty.XLock ( Y page 79) or unlock ( Y page 79) 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 74) and replace it if
necessary ( Y page 74).XLock ( Y page 79) or unlock ( Y page 79) 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.76SmartKeyOpening/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

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

gases may enter the vehicle interior resulting
in unconsciousness and death.
You can open the trunk lid from the driver's
seat when the vehicle is stationary and
unlocked.XTo open: press the upper section of remote
operating switch for trunk lid : until the
trunk lid opens.
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.XInsert the mechanical key into 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 cannot be unlocked with the
SmartKey or KEYLESS-GO, use the
mechanical key.
If you use the mechanical key to unlock and
open the trunk lid, the anti-theft alarm system
will be triggered ( Y page 67).
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
from position 1 as far as it will go to
position 2.
The trunk is unlocked.XTurn the mechanical key back to position
1 and remove it.XInsert the mechanical key into the
SmartKey.
Trunk emergency release
You can open the trunk lid from inside the
vehicle with the emergency release button.
82TrunkOpening/closing

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

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

Adjusting the steering wheel
electrically:To adjust the steering wheel height;To adjust the steering wheel position
(fore-and-aft adjustment)
i Other topics:
R EASY-ENTRY/EXIT feature
( Y page 100)
R storing settings ( Y page 103)
EASY-ENTRY/EXIT system
Important safety notes
The EASY-ENTRY/EXIT feature makes getting
in and out of your vehicle easier.
You can activate and deactivate the EASY-
ENTRY/EXIT feature in the on-board
computer ( Y page 209).
GWARNING
You must make sure no one can become
trapped or injured by the moving steering
wheel when the easy-entry/exit feature is
activated.
To stop steering wheel movement, move
steering wheel adjustment stalk or press the
memory position switch.
Do not leave children unattended in the
vehicle, or with access to an unlocked vehicle.
Children could open the driver's door and
unintentionally activate the easy-entry/exit
feature, which could result in an accident
and/or serious personal injury.
GWARNING
Let the system complete the adjustment
procedure before setting the vehicle in
motion. All steering wheel adjustment must
be completed before setting the vehicle in
motion. Driving off with the steering wheel
still adjusting could cause the driver to lose
control of the vehicle.
Position of the steering wheel when the
EASY-ENTRY/EXIT feature is active
The steering wheel swings upwards when
you:
R remove the SmartKey from the ignition lock
R open the driver's door and KEYLESS-GO is
in position 1
R open the driver's door and the SmartKey is
in position 0 or 1 in the ignition lock
i The steering wheel only moves upwards if
it has not already reached the upper end
stop.
Position of the steering wheel for
driving
The steering wheel is moved to the last
selected position when:
R the driver's door is closed.
R you insert the SmartKey into the ignition
lock.
or
R you press the Start/Stop button once on
vehicles with KEYLESS-GO.
When you close the driver's door with the
ignition switched on, the steering wheel is
also automatically moved to the previously
set position.
The last position of the steering wheel is
stored after each manual setting or when you
store the setting with the memory function
( Y page 103).
100Steering wheelSeats, steering wheel and mirrors

Replacing the wiper blades
Important safety notesGWARNING
For safety reasons, switch off the windshield
wipers and remove the key from the ignition
lock before changing the wiper blades
(vehicles with KEYLESS-GO: make sure that
the on-board electronics are in state 0).
Otherwise, the wiper motor could be switched
on suddenly and cause injury.
! To avoid damaging the wiper blades,
make sure that you touch only the wiper
arm of the wiper.
! Never open the hood if a windshield wiper
arm has been folded away from the
windshield.
Never fold a windshield wiper arm without
a wiper blade back onto the windshield.
Hold the windshield wiper arm firmly when
you change the wiper blade. If you release
the windshield wiper arm without a wiper
blade and it falls onto the windshield, the
windshield may be damaged by the force of
the impact.
Mercedes-Benz recommends that you have
the wiper blades replaced by a qualified
specialist workshop, e.g. at an authorized
Mercedes-Benz Center.
Replacing the windshield wiper blades
Removing the wiper blades
XRemove the SmartKey from the ignition
lock or turn it to position 0 (KEYLESS-GO).XFold the wiper arm away from the
windshield until it engages.XSet the wiper blade at right angles to the
wiper arm.XRemove the wiper blade from the retaining
pin on the wiper arm in the direction of the
arrow.
Installing the wiper blades
XPush the new wiper blade onto the
retaining pin on the wiper arm in the
opposite direction to the arrow.
Make sure that the wiper blade slides fully
onto the retaining pin on the wiper arm.XTurn the wiper blade parallel to the wiper
arm.XFold the wiper arm back onto the
windshield.
Replacing the rear window wiper blade
Removing the wiper blade
XRemove the SmartKey from the ignition
lock.XFold wiper arm : away from the rear
window until it engages.XPosition wiper blade ; at a right angle to
wiper arm :.118Windshield wipersLights and windshield wipers