lock MERCEDES-BENZ C-Class 2011 W204 Owner's Guide

XRoute Top Tether belt A under the head
restraint : between both head restraint
bars.
XHook Top Tether hook ? into Top Tether
anchorage =.
XMake sure that Top Tether belt A is not
twisted.
XFold down cover ; of Top Tether
anchorage =.
XIf necessary, push head restraint : back
down slightly (Y page 96). Make sure that
the routing of Top Tether belt A is not
impaired.
XInstall the LATCH-type (ISOFIX) child
restraint system with Top Tether. Always
comply with the manufacturer's
installation instructions. Make sure that
Top Tether belt A is taut.
Child-proof locks
Child-proof locks for the rear doors
GWarning
Observe "Important safety notes"
(Y page 55).
GWarning
Children could open a rear door from inside
the vehicle. This could result in serious
injuries or an accident. Therefore, when
children ride in the rear always secure the rear
doors with the child-proof locks.
You can secure each door individually with
the child-proof locks on the rear doors. A door
secured with a child-proof lock cannot be
opened from inside the vehicle. When the
vehicle is unlocked, the door can be opened
from the outside.
XTo activate: press the child-proof lock
lever up in the direction of arrow :.
XMake sure that the child-proof locks are
working properly.
XTo deactivate: press the child-proof lock
lever down in the direction of arrow ;.
Override feature for the rear side
windows
GWarning
Observe "Important safety notes"
(Y page 55).
GWarning
When children ride on the vehicle's rear seats,
activate the override switch. Otherwise, the
children could be injured, e.g. by trapping
themselves in the rear side window.
XTo activate/deactivate: press button ;.
If indicator lamp : is lit, operation of the
rear side windows is disabled. Operation is
only possible using the switches in the
driver's door. If indicator lamp : is off,
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operation is possible using the switches in
the rear compartment.
Panic alarm
X To activate: press and hold !
button : for about one second.
An alarm sounds and the exterior lighting
flashes.XTo deactivate: press ! button :
again.
or
XInsert the SmartKey into the ignition lock.
or
XPress the KEYLESS-GO Start-Stop button.
The KEYLESS-GO key must be in the
vehicle.
i USA only:
This device complies with the part 15 of the
FCC regulations. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
2. This device must withstand 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.
i Canada only:
This device complies with the RSS-210
regulations of Industry Canada. Operation
is subject to the following two conditions:
1. This device may not cause interference,
and
2. This device must withstand any
interference received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
R ABS ( Anti-lock Braking System)
R BAS ( Brake Assist System)
R ESP ®
(E lectronic Stability Program)
R EBD ( Electronic Brake-power Distribution)
R ADAPTIVE BRAKE
Important safety notes
GWarning
The following factors increase the risk of
accidents:
R Excessive speed, especially in turns
R Wet and slippery road surfaces
R Following another vehicle too closely
The driving safety systems described in this
section cannot reduce these risks or prevent
the natural laws of physics from acting on the
vehicle. They cannot increase braking or
steering efficiency beyond that afforded by
the condition of the vehicle brakes and tires
or the traction afforded.
Only a safe, attentive, and skillful driver can
prevent accidents.
The capabilities of a vehicle equipped with the
driving safety systems described in this
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section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user's safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear.
i In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible.
ABS (Anti-lock Braking System)
Important safety notes
GWarning
Observe "Important safety notes"
( Y page 61).
GWarning
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal defeats the purpose of the ABS
and significantly reduces braking
effectiveness.
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about
5 mph (8 km/h) upwards, regardless of road-
surface conditions. ABS works on slippery
surfaces, even when you only brake gently.
The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Braking
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
XIf ABS intervenes: continue to depress the
brake pedal with force until the braking
situation is over.XTo make a full brake application:
depress the brake pedal with full force.GWarning
If the ABS malfunctions, other driving systems
such as the BAS or the ESP ®
are also switched
off. Observe indicator and warning lamps that
may come on as well as messages in the
multifunction display that may appear.
If the ABS malfunctions, the wheels may lock
during hard braking, reducing the steering
capability and extending the braking distance.
The pulsating brake pedal can be an
indication of hazardous road conditions and
functions as a reminder to take extra care
while driving.
BAS (Brake Assist)
GWarning
Observe "Important safety notes"
( Y page 61).
BAS operates in emergency braking
situations. If you depress the brake pedal
quickly, BAS automatically boosts the braking
force, thus shortening the stopping distance.
XKeep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated.
GWarning
If the BAS malfunctions, the brake system still
functions, but without the additional brake
boost available that the BAS would normally
provide in an emergency braking maneuver.
Therefore, the braking distance may increase.
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If you deactivate ESP®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels are able to spin. The
spinning of the wheels results in a cutting
action, which provides better grip.
R traction control is still activated.
R ESP ®
still provides support when you brake
firmly.
If ESP ®
is deactivated and one or more wheels
start to spin, the ä warning lamp in the
instrument cluster does not flash. In such
situations, ESP ®
will not stabilize the vehicle.XTo deactivate: press button : until the
å warning lamp lights up in the
instrument cluster.
The message ESC-OFF appears in the
multifunction display.GWarning
When the å ESP OFF warning lamp lights
up, ESP is switched off.
When the ä ESP warning lamp and the
å ESP OFF warning lamp are on
continuously, ESP is not operational due to a
malfunction.
When ESP is switched off or not operational,
the vehicle's stability during standard driving
maneuvers is reduced.
Adapt your driving style to suit the prevailing
road conditions/weather conditions and to
the non-operating status of ESP.
! Avoid spinning a drive wheel for an
extended period with ESP switched off. This
could cause serious damage to the drive
train.XTo activate: briefly press button :.
The å warning lamp in the instrument
cluster goes out. The message ESC-ON
appears in the multifunction display.
EBD
GWarning
Observe "Important safety notes"
( Y page 61).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking.
GWarning!
If the EBD malfunctions, the brake system will
still function with full brake boost. However,
the rear wheels could lock up during
emergency braking situations, for example.
You could lose control of the vehicle and
cause an accident.
Adapt your driving style to the changed
driving characteristics.
Adaptive Brake
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In
addition to the braking function, ADAPTIVE
BRAKE also features the hill start assist
function ( Y page 135). For further
information, see Driving tips ( Y page 152).
Anti-theft systems
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct key.
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When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
key that is left inside the vehicle.
XTo activate with the SmartKey: remove
the SmartKey from the ignition lock.
XTo activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
XTo deactivate: switch on the ignition.
iThe immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be
started when the starter battery is fully
charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in
USA) or 1-800-387-0100 (in Canada).
ATA (Anti-Theft Alarm system)
A visual and audible alarm is triggered if the
alarm system is armed and you open:
Ra door
Rthe vehicle with the mechanical key
Rthe trunk lid
Rthe hood
The alarm is not switched off, even if you
close the open door that has triggered it, for
example.
iIf the alarm stays on for more than 30
seconds, the emergency call system
mbrace (USA only) or TELEAID (Canada
only) initiates a call to the Customer
Assistance Center automatically. The
emergency call system initiates the call
provided that:
Ryou have subscribed to the mbrace/
TELEAID service.
Rthe mbrace/TELEAID service has been
activated properly.
Rthe required mobile phone, power supply
and GPS are available.
XTo arm: lock the vehicle with the SmartKey
or KEYLESS-GO.
Indicator lamp : flashes. The alarm
system is armed after approximately 15
seconds.
XTo deactivate: unlock the vehicle using the
SmartKey or KEYLESS-GO.
XTo stop the alarm using the SmartKey:
insert the SmartKey into the ignition lock.
The alarm is switched off.
or
XPress the % or & button on the
SmartKey.
The alarm is switched off.
XTo stop the alarm using KEYLESS-GO:
grasp the outside door handle. The key
must be outside the vehicle.
The alarm is switched off.
or
XPress the Start/Stop button on the
dashboard. The key must be inside the
vehicle.
The alarm is switched off.
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Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
SmartKey
Important safety notes
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. 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
starter switch 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 by 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
General information
If the SmartKey is faulty, contact Roadside
Assistance or an authorized Mercedes-Benz
Center.
SmartKey functions
Locking and unlocking centrally
The SmartKey centrally locks/unlocks:
R the doors
R the trunk lid
R the fuel filler flap
:& To lock the vehicle;F To unlock the trunk lid=% To unlock the vehicle
When unlocking, the turn signals flash once.
When locking, they flash three times.
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer.
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You can also set an audible signal to confirm
that the vehicle has been locked or unlocked.
The audible signal can be activated and
deactivated using the on-board computer
( Y page 181).
i Only for USA:
This equipment complies with Part 15 of
the FCC regulations. Operation is subject
to the following conditions:
R this equipment must not emit harmful,
electromagnetic radiation.
R this equipment may be affected by
electromagnetic radiation, including
radiation which can trigger unwanted
functions.
Any unauthorized change to this equipment
can lead to the user's operating license
being withdrawn.
i Only for Canada:
This equipment complies with the RSS-210
regulations of Industry Canada. Operation
is subject to the following conditions:
R this equipment must not emit harmful,
electromagnetic radiation.
R this equipment receives electromagnetic
radiation, including radiation which can
trigger unwanted functions.
Any unauthorized change to this equipment
can lead to the user's operating license
being withdrawn.XTo unlock centrally: press the %
button.
If you do not open a door or the trunk lid within
approximately 40 seconds of unlocking the
vehicle:
R the vehicle is locked again.
R the theft deterrent locking system is
activated again.
XTo lock centrally: press the & button.KEYLESS-GO
General notes
i Only for USA:
This equipment complies with Part 15 of
the FCC regulations. Operation is subject
to the following conditions:
R this equipment must not emit harmful,
electromagnetic radiation.
R this equipment may be affected by
electromagnetic radiation, including
radiation which can trigger unwanted
functions.
Any unauthorized change to this equipment
can lead to the user's operating license
being withdrawn.
i Only for Canada:
This equipment has been released in
accordance with RSS - 210 of Industry
Canada. Operation is subject to the
following conditions:
R this equipment must not emit harmful,
electromagnetic radiation.
R this equipment receives electromagnetic
radiation, including radiation which can
trigger unwanted functions.
Any unauthorized change to this equipment
can lead to the user's operating license
being withdrawn.
Important information for using
KEYLESS-GO
R You can use the KEYLESS-GO key as a
conventional key.
R You can combine KEYLESS-GO functions
with those of a conventional key (e.g. open
with KEYLESS-GO and close with the
& button).
R Always carry your KEYLESS-GO key on your
person.
R Never keep the KEYLESS-GO key with:
- electronic equipment, such as your
mobile phone or another key
- metal objects, such as coins or metal foil
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This may impair the functioning of KEYLESS-
GO.
RTo open or close the vehicle, the KEYLESS-
GO key should be no more than 3 ft (1 m)
from the door or trunk.
RWhen the vehicle is parked for more than
72 hours, the KEYLESS-GO function is
deactivated. Pull one of the outer door
handles and turn on the ignition to
reactivate the KEYLESS-GO function.
RIf the KEYLESS-GO key is not near the
vehicle, it is possible that the system may
not recognize it. In this case, the vehicle
cannot be locked or started with KEYLESS-
GO.
RIf the KEYLESS-GO key has been removed
from the vehicle (e.g. if a passenger leaves
the vehicle with the KEYLESS-GO key):
-while someone is holding the Start/Stop
button or attempting to lock the vehicle
with the outer door handle, the message
Key not detected appears in the
multifunction display
-while the engine is running, the red
message Key not detected appears in
the multifunction display as you pull
away. Find the KEYLESS-GO key or
change its current position immediately
(e.g. place it on the front-passenger seat
or carry it in your shirt pocket.)
RIf you have started the engine using the
Start/Stop button, you can turn if off again
by:
-pressing the Start/Stop button again
-inserting the KEYLESS-GO key in the
ignition lock when the vehicle is
stationary and the automatic
transmission is in parking position P.
RYou may accidentally unlock the vehicle if
the KEYLESS-GO key is within 3 ft (1 m) of
the vehicle and:
-an outer door handle comes into contact
with water
or
-you are cleaning an outer door handle.
RNote that the engine can be started by any
vehicle occupant if a KEYLESS-GO key is in
the vehicle.
Option 1: there is a KEYLESS-GO key in the
vehicle and a KEYLESS-GO key outside the
vehicle. If you leave the KEYLESS-GO key
behind when you get out and lock the
vehicle, a message does not appear in the
multifunction display.
Option 2: there is a KEYLESS-GO key in the
vehicle but no KEYLESS-GO key outside the
vehicle. When you get out and try to lock
the vehicle, the message Key still in
vehicle appears in the multifunction
display. The vehicle is not locked in this
case.
When starting the engine and while driving,
KEYLESS-GO also checks whether a valid key
is in the vehicle by periodically establishing
radio contact.
X To unlock the vehicle: touch the inner
surface of the door handle.
XTo lock the vehicle: touch sensor
surface :.
XConvenience closing feature: touch
sensor surface ; for an extended period
(Y page 84).
If you pull on the handle of the trunk lid, only
the trunk/cargo area of the vehicle is
unlocked.
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iIf the vehicle has been parked for a long
time, the sensor surfaces are deactivated
automatically.
Pull the door handle to unlock the door and
turn on the ignition once to activate the
sensor surfaces again.
Changing the settings of the locking
system
You can change the settings 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 the %
and & buttons simultaneously for
approximately six seconds until the battery
check lamp flashes twice.
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 door handle on the front-
passenger door or the rear door.XTo lock centrally: touch sensor
surface : on one of the door handles.
Restoring the factory settings
XPress 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 67).
There are several ways to turn off the alarm:
XPress the % or & button on the
SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XPress 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.
Removing the mechanical key
XPush release catch : in the direction of
the arrow and at the same time remove
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SmartKey battery
Important safety notes
It is advisable to have batteries replaced at a
qualified specialist workshop, e.g. at an
authorized Mercedes-Benz Center.
GWarning!
Batteries are toxic and contain caustic
substances. For this reason, keep batteries
out of the reach of children.
If a battery has been swallowed, visit a doctor
immediately.
GWarning
SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Check with
your local government's disposal guidelines.
California residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Checking the battery
XPress the & or % button.
The SmartKey battery is working properly if
battery charge indicator lamp : lights up
briefly.
If battery charge indicator lamp : does not
light up briefly during the test, the SmartKey
battery is discharged.
XReplace the SmartKey battery
( Y page 74).i
You can obtain a SmartKey battery at any
authorized Mercedes-Benz Center.
i If the SmartKey battery is checked within
signal range of the vehicle, pressing the
& or % button results in the vehicle
being locked or unlocked respectively.
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 the
arrow until battery tray cover : opens. Do
not hold the cover closed while doing so.XRemove the cover of the battery tray.XRepeatedly tap the SmartKey against your
palm until battery = falls out.XInsert the new battery with the positive
pole facing upwards. Use a lint-free cloth to
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