door lock MERCEDES-BENZ C-Class SEDAN 2012 W204 Service Manual

Lights
Switching the daytime running lamps on/
off
This function is not available in Canada.
If you have activated the Day Lights
function and the light switch is in the c or
à position, the daytime running lamps are
switched on automatically during the day
when the engine is running.
In the dark, the following also light up:
R the low-beam headlamps
R the parking lamps
R the tail lamps
R the license plate lamp
R the side marker lamps
XPress the = or ; button on the
steering wheel to select the Sett. menu.XPress the : or 9 button to select the
Lights submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Day Lights function.
If the Daytime Running Lights: function
has been switched on, the cone of light and
the W symbol in the multifunction
display are shown in red.XPress the a button to save the setting.
Switching Adaptive Highbeam Assist on/
off
XPress the = or ; button on the
steering wheel to select the Sett. menu.XPress the : or 9 button to select the
Lights submenu.XPress the a button to confirm.XPress : or 9 to select the Adapt.
Highbeam function.
If the Adapt. Highbeam function has been
switched on, the cone of light and the
_ symbol in the multifunction display
are shown in red.XPress the a button to save the setting.Activating/deactivating surround
lighting and exterior lighting delayed
switch-off
If you have activated the Surround
Lighting function and the light switch is in
the c or à position, the following
functions are active when it is dark:
R Surround lighting: the exterior lighting
remains lit for 40 seconds after unlocking
with the SmartKey. The exterior lighting
switches off when you open the driver's
door.
R Exterior lighting delayed switch-off: the
exterior lighting remains lit for 60 seconds
after the engine has been switched off. If
you close all the doors, the exterior lighting
goes off after 15 seconds.
If you activate the Surround Lighting
function, the following light up depending on
the vehicle's equipment:
R the parking lamps
R the fog lamps
R the daytime running lamps
R the side marker lamps
R the surround lighting in the exterior mirrorsXPress the = or ; button on the
steering wheel to select the Sett. menu.XPress the : or 9 button to select the
Lights submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Surround lighting function.
When the Surround Lighting function is
activated, the light cone and the area
around the vehicle are displayed in red in
the multifunction display.XPress the a button to save the setting.Menus and submenus207On-board computer and displaysZ

Deactivating delayed switch-off of the
exterior lighting temporarily:XBefore leaving the vehicle, turn the
SmartKey to position 0 in the ignition lock.XTurn the SmartKey to position 2 in the
ignition lock and back to position 0.
The exterior lighting delayed switch-off is
deactivated.
Delayed switch-off of the exterior lighting is
reactivated the next time you start the
engine.
Activating/deactivating the interior
lighting delayed switch-off
If you activate the Light. delay function,
the interior lighting remains on for 20
seconds after you remove the SmartKey from
the ignition lock.
XPress the = or ; button on the
steering wheel to select the Settings
menu.XPress the : or 9 button to select the
Lights submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Light. Delay function.
When the Light. Delay function is
activated, the vehicle interior is displayed
in red in the multifunction display.XPress the a button to save the setting.
Vehicle
Activating/deactivating the automatic
door locking feature
If you select the Auto. Door Locks
function, the vehicle is centrally locked above
a speed of around 9 mph (15 km/h).
i For further information on the automatic
locking feature, see ( Y page 78).
XPress the = or ; button on the
steering wheel to select the Settings
menu.XPress the : or 9 button to select the
Vehicle submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Auto. Door Locks function.
When the Auto. Door Locks function is
activated, the vehicle doors are displayed
in red in the multifunction display.XPress the a button to save the setting.
Activating/deactivating the acoustic
locking verification signal
If you activate the Acoustic Lock function,
an audible signal sounds depending on the
vehicle's date of manufacture:
R when locking
or
R once when unlocking and three times when
locking
XPress the = or ; button on the
steering wheel to select the Settings
menu.XPress the : or 9 button to select the
Vehicle submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Acoustic Lock function.
If the Acoustic Lock function is activated,
the & symbol in the multifunction
display lights up red.XPress the a button to save the setting.
Activating/deactivating the radar sensor
system
The following systems are switched off when
the radar sensor system is deactivated:
R DISTRONIC PLUS ( Y page 161)
R BAS PLUS ( Y page 60)
R PRE-SAFE ®
Brake ( Y page 65)
208Menus and submenusOn-board computer and displays

RBlind Spot Assist ( Y page 183)
R Active Blind Spot Assist ( Y page 187)
i USA only: This device has been approved
by the FCC as a "Vehicular Radar System".
The radar sensor is intended for use in an
automotive radar system only. Removal,
tampering, or altering of the device will void
any warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.XPress the = or ; button on the
steering wheel to select the Settings
menu.XPress the : or 9 button to select the
Vehicle submenu.XPress the a button to confirm.XPress the 9 or : button to select
Radar Sensor (See Oper. Manual): .
You will see the selected setting: Enabled
or Disabled .XPress the a button to save the setting.
Convenience
Activating/deactivating the EASY-
ENTRY/EXIT feature
You can use the Easy Entry/Exit: function
to activate or deactivate the EASY ENTRY/
EXIT feature ( Y page 100).
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 lever or press one
of the memory position buttons.
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.
XPress the = or ; button on the
steering wheel to select the Sett. menu.XPress the : or 9 button to select the
Convenience submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Easy Entry/Exit function.
If the Easy Entry/Exit function is
activated, the vehicle steering wheel is
displayed in red in the multifunction
display.XPress the a button to save the setting.
Switching the fold-in mirrors when
locking function on/off
This function is only available in Canada.
If you switch on the Auto. Mirror
Folding function, the exterior mirrors fold in
when you lock the vehicle. If you unlock the
vehicle and then open the driver's or front-
passenger door, the exterior mirrors fold out
again.
If you have switched the function on and you
fold the exterior mirrors in using the button
on the door ( Y page 101), they will not fold
out automatically. The exterior mirrors can
then only be folded out using the button on
the door.
Menus and submenus209On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutionsh
Check Tire PressureGRisk of accident
The tire pressure in one or more tires has dropped significantly.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 334).XCheck the tire pressure. If necessary, correct the tire pressure
( Y page 319).h
Correct Tire
PressureThe tire pressure is too low in at least one of the tires or the tire
pressure difference between the wheels is too great.XCheck the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 319).
Vehicle
Display messagesPossible causes/consequences and M SolutionsShift to 'P' or 'N'
to Start EngineYou have attempted to start the engine with the transmission in
position R or D.XShift the transmission to position P or N.P
Shift to 'P'You have attempted to stop the engine with the Start/Stop button
while the transmission was not in position P.XShift the transmission to position P.While the HOLD function or DISTRONIC PLUS is active, you have:
R opened the driver's door and released the seat belt or
R switched off the engine or
R opened the hood
A tone may also sound at regular intervals. The tone becomes
louder if you attempt to lock the vehicle.
You cannot start the engine.XShift the transmission to position P.
You can restart the engine.NThe trunk lid is open.XClose the trunk lid.236Display messagesOn-board computer and displays

SmartKeyDisplay messagesPossible causes/consequences and M SolutionsÂ
Key Does Not
Belong to VehicleYou have put the wrong SmartKey in the ignition lock.XUse the correct SmartKey.Â
Take Your Key from
IgnitionThe SmartKey is in the ignition lock.XRemove the SmartKey.Â
Obtain a New KeyThe SmartKey needs to be replaced.XVisit a qualified specialist workshop.Â
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 74).Â
Don't Forget Your
KeyThe display message is shown for a maximum of 60 seconds and
is only a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.XRemember to take the KEYLESS-GO key with you when you
leave the vehicle.Â
Key Not Detected
(red display message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XOperate the vehicle with the SmartKey in the ignition lock.238Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsÂ
Key Not Detected
(White display
message)The KEYLESS-GO key cannot be detected at present.XChange the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
XOperate the vehicle with the SmartKey in the ignition lock.Â
Key Detected in
VehicleThe KEYLESS-GO key has been detected inside the vehicle during
locking.XRemove the KEYLESS-GO key from the vehicle.Â
Remove 'Start'
Button and Insert
KeyKEYLESS-GO is temporarily malfunctioning or is defective. A
warning tone also sounds.XInsert the SmartKey into the ignition lock and turn it to the
desired position.XVisit a qualified specialist workshop.Â
Close Doors to
Lock VehicleAt least one door is open. A warning tone also sounds.XClose all doors and lock the vehicle again.
Warning and indicator lamps in the instrument cluster
Seat belt
ProblemPossible causes/consequences and M Solutions7
After starting the
engine, the red seat
belt warning lamp lights
up for six seconds.The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.XFasten your seat belt ( Y page 48).7
After starting the
engine, the red seat
belt warning lamp lights
up. In addition, a
warning tone sounds
for up to six seconds.GRisk of injury
The driver's seat belt is not fastened.
XFasten your seat belt ( Y page 48).
The warning tone ceases.Warning and indicator lamps in the instrument cluster239On-board computer and displaysZ

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 24).
Loading guidelines
GWARNING
Always fasten items being carried as securely
as possible using fastening materials
appropriate for the weight and size of the
load.
In an accident, during hard braking or sudden
maneuvers, loose items will be thrown around
inside the vehicle. This can cause injury to
vehicle occupants unless the items are
securely fastened in the vehicle.
To help avoid personal injury during a collision
or sudden maneuver, exercise care when
transporting cargo. Do not pile luggage or
cargo higher than the seat backrests.
The trunk is the preferred place to carry
objects. Do not place anything on the rear-
window shelf.
Never drive a vehicle with the trunk open.
Deadly carbon monoxide (CO) gases may
enter vehicle interior resulting in
unconsciousness and death.
The handling characteristics of a laden
vehicle are dependent on the distribution of
the load within the vehicle. For this reason,
you should observe the following notes when
transporting a load:
R when transporting a load, never exceed the
maximum permissible gross vehicle weight
or the gross axle weight rating of the
vehicle (including occupants). The values
are specified on the vehicle identification
plate on the B-pillar of the driver's door.
R position heavy loads as far forwards as
possible and as low down in the trunk as
possible.
R the load must not protrude above the upper
edge of the seat backrests.
R always place the load against the rear or
front seat backrests. Make sure that the
seat backrests are securely locked into
place.
R always place the load behind unoccupied
seats if possible.
R secure the load with sufficiently strong and
wear-resistant tie down. pad sharp edges
for protection.
Stowage areas
Stowage compartments
Important safety notes
GWARNING
To help avoid personal injury during a collision
or sudden maneuver, exercise care when
storing objects in the vehicle. Put luggage or
cargo in the trunk if possible.
Do not pile luggage or cargo higher than the
seat backrests.
Keep compartment lids closed. This will help
to prevent stored objects from being thrown
about and injuring vehicle occupants during
R braking
R vehicle maneuvers
R an accident
Stowage compartments in the front
Glove box
i The glove box can be cooled
( Y page 132).
254Stowage areasStowing and features

XPull or push the sun visor in the direction of
the arrow.
Sunblinds on the rear side windows
XTo extend: pull the roller sunblind out by
tab : and hook it onto retainers ; at the
top of the window.
! Always guide the roller sunblind by hand.
Do not let it snap back suddenly as this
would damage the automatic roller
mechanism.
! Do not drive the vehicle with the roller
sunblind hooked in and the side windows
opened simultaneously. The roller sunblind
can jump out of the retainers and spring
back suddenly when driving at high speeds,
e.g. when driving on the freeway. This could
damage the inertia reel. Therefore, either
close the side window or retract the roller
sunblind before driving at high speeds.
Rear window roller sunblind (Sedan)
Important safety notesGWARNING
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 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
ignition lock 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 on these
parts.
GWARNING
When adjusting a roller sunblind, the roller
blind moves up or down. You might become
trapped in the process.
In the event of danger, briefly press the button
for the roller sunblind to change the roller
blind's direction of movement.
Extending/retracting the roller
sunblind
! Make sure that the roller sunblind can
move freely. Otherwise, the roller sunblind
or other objects could be damaged.
Features261Stowing and featuresZ

even if the SmartKey is removed from the
ignition lock 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 on these
parts.GWARNING
Never touch the heating element or sides of
the lighter; they are extremely hot. Hold the
knob only.
Make sure any children traveling with you do
not injure themselves or start a fire with the
hot cigarette lighter.
XTurn the SmartKey to position 2 in the
ignition lock.XTo open: slide cover : forwards until it
engages.XPress in cigarette lighter ;.
Cigarette lighter ; will pop out
automatically when the heating element is
red-hot.XTo close: press cover : briefly at the
front.
The cover moves back.12 V sockets
Points to observe before use
The sockets can be used for accessories, e.g.
lamps or mobile phone chargers with a
maximum current draw of 180 W (15 A).
If you use the sockets for long periods when
the engine is switched off, the battery may
discharge.
XTurn the SmartKey to position 1 in the
ignition lock.
i An emergency cut-out ensures that the
on-board voltage does not drop too low. If
the on-board voltage is too low, the power
to the sockets is automatically cut. This
ensures that there is sufficient power to
start the engine.
Socket in the rear-compartment center
console
XPull cover ; out by its top edge.XLift up the cover of socket :.
115 V power socket
GWARNING
The 115V AC socket operates at high voltage.
Use the 115V AC socket in the vehicle with
the same caution and prudence that you
exercise when using power outlets at home.
Keep any fluids away from the 115V AC
socket. Do not clean the socket with fluids or
tapered objects. Keep the 115V AC socket
Features263Stowing and featuresZ

The SOS button flashes and the
Connecting Call message appears in the
multifunction display to confirm that the
command for vehicle remote unlocking has
been received.
If you pull the trunk handle for more than
20 seconds before receiving authorization
for remote unlocking, you must wait 15
minutes before you can pull the trunk lid
handle again.
Remote vehicle locking
If you forget to lock your vehicle but are no
longer in the vicinity of the vehicle, it can be
locked for you by the Mercedes-Benz
Customer Assistance Center.
The vehicle can be locked remotely up to four
days after the ignition was last switched off.
XContact the following service hotlines:
R USA: Mercedes-Benz Customer
Assistance Center under 1-800-FOR-
MERCedes(1-800-367-6372) or
1-888-990-9007
R Canada: Customer Service at
1-888-923-8367
You will be asked for your PIN.
The next time you are in your vehicle and
switch on the ignition, the Tele Aid Doors
locked by remote control message
appears in the multifunction display.
Alternatively, the vehicle can also be locked
via the Internet or an iPhone in the "Owners
Online" section using your ID number and
password.
i The vehicle valet locking feature is
available when the relevant mobile phone
network is available and data connection is
possible.
Service for recovering a stolen vehicle
If your vehicle has been stolen:
XNotify the police.
The police will issue a numbered incident
report.XThis number will be forwarded to the
Mercedes-Benz Customer Assistance
Center together with your PIN.
The Mercedes-Benz Customer Assistance
Center then attempts to locate the mbrace
system. The Mercedes-Benz Customer
Assistance Center contacts you and the
local law enforcement agency if the vehicle
is located. However, only the law
enforcement agency is informed of the
location of the vehicle.
i If the anti-theft alarm system is active for
longer than 30 seconds, mbrace
automatically informs the Mercedes-Benz
Customer Assistance Center.
Garage door opener
Important safety notes
The HomeLink ®
garage door opener
integrated in the rear-view mirror allows you
to operate up to three different door and gate
systems.
i Certain garage door drives are
incompatible with the integrated garage
door opener. If you have difficulty
programming the integrated garage door
opener, contact an authorized Mercedes-
Benz Center or call one of the following
telephone hotlines:
R USA: Mercedes-Benz Customer
Assistance Center at
1-800-FOR-MERCedes
R Canada: Customer Service at
1-800-387-0100
GWARNING
Before programming the integrated remote
control to a garage door opener or gate
270FeaturesStowing and features