child lock MERCEDES-BENZ B-CLASS 2012 User Guide

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 Read the information on qualified
specialist workshops: ( Y page 24).SmartKey
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shift the automatic transmission out of
parking position P.
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you

and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. G
WARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be
unintentionally turned in

the ignition lock. This
could cause the engine to be switched off.
There is a risk of an accident.
Do not attach any heavy or large objects to
the SmartKey. Remove any bulky key rings
before inserting the SmartKey into the
ignition lock.
! Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not keep the SmartKey:
R with electronic devices, e.g. a mobile
phone or another SmartKey
R with metallic objects, e.g. coins or metal
foil
R inside metallic objects, e.g. a metal case SmartKey functions
:
& To lock the vehicle
; % To unlock the vehicle
X To unlock centrally: press button ;.
If you do not open the vehicle within
approximately 40 seconds of unlocking:
R the vehicle is locked again.
R the theft

deterrent locking system is armed
again. 68
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Opening and closing
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SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and corrosive
substances. If batteries
are swallowed, it can
result in severe health problems. There is a
risk of fatal injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National
guidelines must be observed during disposal.
In California, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Mercedes-Benz recommends that you have
the batteries replaced at a qualified specialist
workshop.
Checking the battery X
Press the & or % button.
The battery is working properly if battery
check lamp : lights up briefly.
The battery is discharged if battery check
lamp : does not light up briefly.
X Change the battery ( Y page 70). i
If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the &

or % button:
R locks or
R unlocks the vehicle
i You can get a battery at any qualified
specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.
X
Take the mechanical key out of the
SmartKey (Y page 69). X
Press mechanical key ; into the opening
in the SmartKey in the direction of the
arrow until battery tray cover : opens.
When doing so,

do not hold cover : shut.
X Remove battery tray cover :. X
Repeatedly tap the SmartKey against your
palm until battery = falls out.
X Insert the new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so.70
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Problem Possible causes/consequences and
M SolutionsThe engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 285).
or
X Jump-start the vehicle (Y page 289).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the
SmartKey. The steering lock is mechanically blocked.
X
Remove the SmartKey and reinsert it into the ignition lock. While
doing this, turn the steering wheel in both directions. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shift the automatic transmission out of
parking position P.
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you
and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. Unlocking and opening doors from
the inside
X
To unlock a front door: pull door
handle ;.
Locking knob : pops up.
The door is unlocked and can be opened. Doors
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X
To open a front door: pull door
handle ;.
X To unlock a rear door: pull up locking
knob :.
The door is unlocked and can be opened.
X To open a rear door: pull door handle ;.
You can open a door from inside the vehicle
even if it has been locked. You can open the
rear doors from
inside the vehicle unless they
are secured by the child-proof lock
(Y page 58).
If the vehicle has previously been locked with
the SmartKey, opening a door from the inside
will trigger the anti-theft alarm system.
Switch off the alarm (Y page 65). Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside.

This can be useful if you wish
to lock the vehicle before pulling away, for
example. X
To unlock: press button :.
X To lock: press button ;.
The vehicle locks when all the doors and
the tailgate are closed.
Meanwhile, the fuel filler flap will not be
locked or unlocked.
You cannot unlock the vehicle centrally from
the inside if

the vehicle has been locked with
the SmartKey. You can open a door from inside the vehicle
even if it has been locked. You can open the
rear doors
from

inside the vehicle unless they
are secured by the child-proof lock
(Y page 58).
If the vehicle has previously been locked with
the SmartKey, opening a door from the inside
will trigger the anti-theft alarm system.
Switch off the alarm (Y page 65).
If the vehicle has been locked using the
locking button for the central locking, or has
been locked automatically, and a door is
opened from the inside:
R the vehicle will be fully unlocked if it had
previously been fully unlocked
R only the door which has been opened form
the inside is unlocked if only the driver's
door had been previously unlocked Automatic locking feature
X
To deactivate: press and hold button :
for about five

seconds until a tone sounds.
X To activate: press and hold button ; for
about five seconds until a tone sounds.
i If you press one of the two buttons and
do not
hear

a tone, the relevant setting has
already been selected.
The vehicle is locked automatically when the
ignition is switched on and the wheels are
turning. 74
Doors
Opening and closing
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particularly if the vehicle is moving, exhaust
fumes could enter the passenger
compartment. There is a risk of poisoning.
Turn off the engine before opening the
tailgate. Never drive with the tailgate open.
G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
! The tailgate swings upwards and to the
rear when opened. Therefore, make sure
that there is
sufficient clearance above and
behind the tailgate.
i The opening dimensions of the tailgate
can be found in the "Vehicle data" section
(Y page 335).
You should preferably place luggage or loads
in the cargo compartment. Observe the
loading guidelines ( Y page 236).
Do not leave the SmartKey in the cargo
compartment. You could otherwise lock
yourself out.
The tailgate can be:
R opened and closed manually from outside
R unlocked from inside with the mechanical
key Opening/closing from outside
Opening X
Press the % button on the SmartKey. X
Pull handle :.
X Raise the tailgate.
Closing X
Pull the tailgate down using handle :.
X Allow the tailgate to drop into the lock.
X If necessary, lock the vehicle with the
& button on the SmartKey. Tailgate emergency release
If the tailgate can no longer be opened from
outside the vehicle, use the emergency
release on the inside of the tailgate.
! The tailgate swings upwards and to the
rear when opened. Therefore, make sure
that there is

sufficient clearance above and
behind the tailgate.
i The opening dimensions of the tailgate
can be found in the "Vehicle data" section
(Y page 335). 76
Cargo compartment
Opening and closing
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You can reach the emergency release via the
cargo compartment. Fold the rear backrests
forward (
Y page 240).
X Take the mechanical key out of the
SmartKey (Y page 69). X
Insert mechanical key ; into the opening
in paneling :.
X Turn mechanical key ; 90° clockwise.
X Push mechanical key ; in the
direction of
the arrow and open the tailgate. Side windows
Important safety notes
G
WARNING
While opening the side windows, body parts
in the closing area could become trapped.
There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure. If
somebody becomes trapped, release the
switch or press the switch to open the side
window again. G
WARNING
If children operate the side windows they
could become trapped,

particularly if they are
left unsupervised. There is a risk of injury.
Activate the override feature for the rear side
windows. When leaving the vehicle, always
take the SmartKey with you and lock the
vehicle. Never leave children unsupervised in
the vehicle. Side window reversing feature
The side windows are equipped with an
automatic reversing feature. If a solid object
blocks or restricts a side window during the
closing process, the

side window opens again
automatically. However, the automatic
reversing feature is only an aid and does not
relieve you of the responsibility of paying
attention when closing a side window. G
WARNING
The reversing feature does not react:
R to soft, light and thin objects, e.g. small
fingers
R over the last

4 mm of the closing movement
R during resetting
R when closing the side window again
manually immediately after automatic
reversing
This means that the reversing feature cannot
prevent someone being trapped in these
situations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure. If
someone becomes trapped, press the switch
to open the side window again. Opening and closing the side
windows
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. Side windows
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Opening and closing Z
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If a side window is obstructed again during
closing and reopens again slightly:
X
Immediately after the window blocks, pull
the corresponding switch again until the
side window has closed.
The side window
is closed without the anti-
entrapment feature. Panorama roof with power tilt/sliding
panel
Important safety notes
In the following section, the term "sliding
sunroof" refers to the panorama roof with
power tilt/sliding panel. G
WARNING
While opening and closing the sliding sunroof,
body parts in close proximity could become
trapped. There is a risk of injury.
Make sure that no body parts are in close
proximity during the opening and closing
procedures.
If somebody becomes trapped:
R release the switch immediately, or
R during automatic operation, push the
switch briefly in any direction
The opening or closing procedure will be
stopped. G
WARNING
If children operate the sliding sunroof they
could become trapped,

particularly if they are
left unsupervised. There is a risk of injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
! Only open the sliding sunroof if it is free
of snow and ice. Otherwise, malfunctions
may occur.
Do not allow anything to protrude from the
sliding sunroof. Otherwise, the seals could
be damaged. !
The weather can

change abruptly. It could
start to rain or snow. Make sure that the
sliding sunroof is closed when you leave the
vehicle. The vehicle electronics can be
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. Sliding sunroof reversing feature
The sliding sunroof is equipped with an
automatic reversing feature. If a solid object
blocks or restricts the sliding sunroof during
the closing process,

the sliding sunroof opens
again automatically. However, the automatic
reversing feature is only an aid and does not
relieve you of the responsibility of paying
attention when closing the sliding sunroof. G
WARNING
The reversing feature does not react:
R to soft, light and thin objects, e.g. small
fingers
R over the last

4 mm of the closing movement
R during resetting
R when closing the sliding sunroof again
manually immediately after automatic
reversing
This means that the reversing feature cannot
prevent someone being trapped in these
situations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure.
If somebody becomes trapped:
R release the switch immediately, or
R during automatic operation, push the
switch briefly in any direction
The closing process is stopped. 80
Panorama roof with power tilt/sliding panel
Opening and closing
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Seats
Important safety notes
G
WARNING
Children could become trapped if they adjust
the seats, particularly when unattended.
There is a risk of injury.
When leaving the vehicle, always take the
SmartKey with you
and lock the vehicle. Never
leave children unsupervised in the vehicle. G
WARNING
You could lose control of your vehicle if you
do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint,
steering wheel and mirror and fasten your
seat belt before starting the engine. G
WARNING
If you adjust the seat height carelessly, you or
other vehicle occupants

could be trapped and
thereby injured. Children in particular could
accidentally press the electrical seat
adjustment buttons and become trapped.
There is a risk of injury.
While moving the seats, make sure that your
hands or other body parts do not get under
the lever assembly of the seat adjustment
system. G
WARNING
When you adjust a seat, you or other vehicle
occupants could become

trapped, e.g. on the
seat guide rail. There is a risk of injury.
Make sure when adjusting a seat that no one
has any body parts in the sweep of the seat. G
WARNING
The seat belt does not offer the intended level
of protection if the backrest is not in the
upright position. When

braking or in the event of an accident, you could slide underneath the
seat belt and sustain abdomen or neck
injuries, for
example.

This poses an increased
risk of injury or even fatal injury.
Adjust the seat properly before beginning
your journey. Always make sure that the seat
is in the upright position. G
WARNING
If head restraints are not installed and
adjusted correctly, they cannot provide
protection as intended.

There is an increased
risk of injury in the head and neck area, e.g.
in the event of an accident or when braking.
Always drive with the head restraints
installed. Before driving off, make sure for
every vehicle occupant that the center of the
head restraint supports the back of the head
at about eye level. G
WARNING
According to accident statistics, children are
safer when properly restrained on the rear
seats than on

the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seat whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriately sized
child restraint system or booster seat
recommended for the size and weight of the
child. For additional information, see the
"Children in the vehicle" section.
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.
! To avoid damage to the seats and the seat
heating, observe the following information:
R keep liquids from spilling on the seats. If
liquid is spilled on the seats, dry them as
soon as possible.
R if the seat covers are damp or wet, do not
switch on the seat heating. The seat Seats
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Switching the seat heating on/off
Activating/deactivating G
WARNING
Repeatedly switching on the seat heating can
cause the seat cushion and backrest pads to
become very hot. The health of persons with
limited temperature sensitivity or a limited
ability to react to excessively high
temperatures may be affected or they may
even suffer burn-like injuries. There is a risk
of injury.
Therefore, do not switch the seat heating on
repeatedly. The three red indicator lamps in the button
indicate the heating level you have selected.
The system automatically switches down
from level 3 to level 2 after approximately
eight minutes.
The system automatically switches down
from level
2
to level 1 after approximately ten
minutes.
The system automatically switches off
approximately 20 minutes after it is set to
level 1.
X Make sure that the SmartKey is in position
1 or 2 in the ignition lock.
X To switch on: press button : repeatedly
until the desired heating level is set.
X To switch off: press button : repeatedly
until all the indicator lamps go out.
i If the battery voltage is too low, the seat
heating may switch off. Problems with the seat heating The seat heating 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.
X
Switch off electrical consumers that you do
not need, such as the rear window
defroster or interior lighting. Steering wheel
Important safety notes
G
WARNING
You could lose control of your vehicle if you
do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint,
steering wheel and mirror and fasten your
seat belt before starting the engine. G
WARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you

and lock the vehicle. Never
leave children unsupervised in the vehicle. Adjusting the steering wheel
G
WARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident.
Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion. Steering wheel
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Memory functions
Storing settings
G
WARNING
If you use the memory function on the driver's
side while driving, you could lose control of
the vehicle as a result of the adjustments
being made. There is a risk of an accident.
Only use the
memory function on the driver's
side when the vehicle is stationary. G
WARNING
When the memory function adjusts the seat,
you and other

vehicle occupants – particularly
children – could become trapped. There is a
risk of injury.
While the memory function is making
adjustments, make sure that no one has any
body parts in the sweep of the seat. If
somebody becomes trapped, immediately
release the memory function position button.
The adjustment process is stopped. G
WARNING
Children could become trapped if they
activate the memory function, particularly
when unattended. There is a risk of injury.
When leaving the vehicle, always take the
SmartKey with you

and lock the vehicle. Never
leave children unsupervised in the vehicle.
With the memory function, you can store up
to three different settings, e.g. for three
different people.
The following settings are stored as a single
memory preset:
R position of the seat, backrest and head
restraint
R driver's side: position of the exterior
mirrors on the driver's and front-passenger
sides X
Adjust the seat ( Y page 88).
X Adjust the exterior mirror on the driver's
side ( Y page 92).
X Briefly press the M memory button and
then press storage position button 1, 2 or
3 within three seconds.
The settings are stored in the selected
preset position. A tone sounds when the
settings have been completed. Calling up a stored setting
X Press and hold the relevant storage
position button 1, 2 or 3
until the

seat and
exterior mirrors are in the stored position.
i The setting procedure is interrupted as
soon as you release the storage position
button. Memory functions
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