2012 MERCEDES-BENZ B-CLASS lock

Characteristics when ESP
®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ ESP®
warning lamp in
the instrument cluster flashes. In such
situations, ESP ®
will not stabilize the vehicle.
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 ETS is still active.
R ESP ®
still provides support when you
brake. EBD (electronic brake force
distribution)
i Observe the "Important safety notes"
section for driving safety systems
(Y page 59). G
WARNING
If EBD has malfunctioned, the rear wheels can
still lock, e.g. under full braking. This
increases the risk

of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified
specialist workshop.
Observe information regarding indicator and
warning lamps ( Y page 225) as well as
display messages ( Y page 203).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking. ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In
addition to the braking function, ADAPTIVE
BRAKE also has the HOLD function
(Y page 168) and hill start assist (Y page 136). For further information, see
Driving tips (Y page 154).
STEER CONTROL
STEER CONTROL helps

you by transmitting a
noticeable steering force to the steering
wheel in the direction required for vehicle
stabilization.
This steering assistance is provided in
particular if:
R both right wheels or both left wheels are on
a wet or slippery road surface when you
brake
R the vehicle starts to skid
If ESP ®
is malfunctioning, you will not receive
steering support from STEER CONTROL.
Power steering will, however, continue to
function. Theft deterrent locking system
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
X To activate: remove the SmartKey from
the ignition lock.
X To deactivate: switch on the ignition.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
i The 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 the
USA) or 1-800-387-0100 (in Canada). 64
Theft deterrent locking system
Safety
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ATA (anti-theft alarm system)
X
To arm: lock the vehicle with the
SmartKey.
Indicator lamp : flashes. The alarm
system is armed after approximately
15 seconds.
X To disarm: unlock the vehicle with the
SmartKey.
or
X Insert the SmartKey into the ignition lock.
A visual and audible alarm is triggered if the
alarm system is armed and you open:
R the vehicle with the mechanical key
R a door
R the tailgate
R the hood
X To stop the alarm: insert the SmartKey
into the ignition lock.
The alarm is switched off.
or
X Press the % or & button on the
SmartKey.
The alarm is switched off.
The alarm is not switched off, even if you
close the open door that triggered it, for
example. i
If the alarm stays on for more than
30 seconds, the Tele
Aid system initiates a
call to the Customer Assistance Center
automatically. The Tele Aid system will
initiate the call provided that:
R you have subscribed to the Tele Aid
service.
R the Tele Aid service has been activated
properly.
R the necessary mobile phone, power
supply and GPS coverage are available. Theft deterrent locking system
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Safety Z
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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
SmartKey
Opening and closing
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X
To lock centrally: press button :.
The SmartKey centrally locks/unlocks:
R the doors
R the tailgate
R the fuel filler flap
The turn signals flash once when unlocking
and three times when locking.
i When it is
dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 198).
i You can also set an audible signal to
confirm that the vehicle has been locked.
The audible signal can be activated and
deactivated using the on-board computer
(Y page 199). Changing the settings of the locking
system
You can change the settings of the locking
system. When you then unlock the vehicle
only the driver's door and the fuel filler flap
are unlocked. This is useful if you frequently
travel on your own.
X To change the setting: press and hold
down the % and & buttons
simultaneously for approximately six
seconds until the battery check lamp
(Y page 70) flashes twice.
i If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the &

or % button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock the driver's door: press the
% button once.
X To unlock centrally: press the %
button twice.
X To lock centrally: press the & button.
X To restore the factory settings: press
and hold down

the % and & buttons simultaneously for approximately six
seconds until the battery check lamp
flashes twice (
Y page 70). Mechanical key
General notes If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered (
Y page 65).
There are several ways to turn off the alarm:
X Press the

% or & button on the
SmartKey.
or
X Insert the SmartKey into the ignition lock.
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked
automatically.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key X
Push release catch : in the direction of
the arrow and at the same time remove
mechanical key ; from the SmartKey. SmartKey
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Opening and closing Z
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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
SmartKey
Opening and closing
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Problems with the SmartKey
Problem Possible causes/consequences and
M SolutionsYou cannot lock or
unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X
Try 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 % or
& button.
If this does not work:
X Check the SmartKey battery and replace it if necessary
(Y page 70).
X Unlock ( Y page 75) or lock ( Y page 75) the vehicle using the
mechanical key. There is interference from a powerful source of radio waves.
X
Try 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. The SmartKey is faulty.
X
Unlock ( Y page 75) or lock ( Y page 75) the vehicle using the
mechanical key.
X Have the SmartKey checked at a qualified specialist workshop. You have lost a
SmartKey. X
Have the SmartKey deactivated at a qualified specialist
workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well.72
SmartKeyOpening and closing
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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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Opening and closing Z
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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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