2012 MERCEDES-BENZ A CLASS ignition

Useful information
i This Owner's Manual describes all mod-
els,
series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos-
sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 24). Key
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 shift the manual transmission into neutral.
R start the engine.
There is a risk of an accident and injury.
When

leaving the vehicle, always take the key
with you and lock the vehicle. Never leave
children or animals unattended in the vehicle.
Always keep the key out of reach of children. G
WARNING
If persons (particularly children) are exposed
to heat or cold for a prolonged period, there
is

a risk of serious or even fatal injuries. Never
leave persons (particularly children) unatten-
ded in the vehicle. G
WARNING
If you attach heavy or large objects to the key,
the
key 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 key. Remove any bulky keyrings before
inserting the key into the ignition lock.
! Keep the key away from strong magnetic
fields. Otherwise, the remote control func-
tion could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not keep the key:
R with electronic devices, e.g. a mobile
phone or another key
R with metallic objects, e.g. coins or metal
film
R inside metallic objects, e.g. a metal case
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside.

People in the vehicle can no longer get
out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked with the key,
then the double lock function is activated as
standard. You can deactivate the double lock
function by deactivating the interior motion
sensor (Y page 70). The doors can then be
opened from the inside after the vehicle has
been locked from the outside. The anti-theft
alarm system is triggered if the door is
opened from the inside. Switch off the alarm
(Y page 69). 74
Key
Opening and closing

Key functions
:
& To lock the vehicle
; % To unlock the vehicle
X To unlock centrally: press button ;.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
R the vehicle is locked again.
R the anti-theft system is primed again.
X To lock centrally: press button :.
The key centrally locks/unlocks:
R the doors
R the tailgate
R the fuel filler flap
When unlocking, the turn signals flash once.
When locking, they flash three times.
i When

it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 222).
i You can also set an audible signal to con-
firm that the vehicle has been locked. The
audible signal can be activated and deacti-
vated using the on-board computer
(Y page 223). Changing the settings of the locking
system
You can change the settings of the locking
system.

This means that only the driver's door
and the fuel filler flap are unlocked when the
vehicle is unlocked. This is useful if you fre-
quently travel on your own.
X To change the setting: press and hold
down the % and & buttons simulta-
neously

for approximately six seconds until
battery check lamp (Y page 76) flashes
twice.
i If the setting of the locking system is
changed
within the signal range of the vehi-
cle, pressing the & or % button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock the driver's door: press the
% button once.
X To unlock centrally: press the % but-
ton 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 sec-
onds until the battery check lamp flashes
twice (Y page 76). Emergency key element
General notes If the vehicle can no longer be unlocked with
the key, use the emergency key element.
If you use the emergency key element to
unlock and open the driver's door, the anti-
theft alarm system will be triggered
(Y page 69).
There are several ways to turn off the alarm:
X
Press the % or &
button on the key.
or
X Insert the key into the ignition lock. Key
75
Opening and closing Z

If you unlock the vehicle using the emergency
key element, the fuel filler flap will not be
unlocked automatically.
X
To unlock the fuel filler flap: insert the
key into the ignition lock.
Removing the emergency key element X
Push release catch : in the direction of
the arrow and at the same time, remove
emergency key element ; from the key. Battery of the key
Important safety notes G
WARNING
Batteries contain toxic and corrosive substan-
ces. 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. H
Environmental note Batteries contain pollutants.
It

is illegal to dispose of them
with the household rubbish.
They must be collected sep-
arately and disposed of in an environmentally responsible
recycling system.
Dispose of batteries in an
environmentally responsible
manner. Take discharged
batteries to a qualified spe-
cialist workshop or to a col-
lection

point for used batter-
ies.
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 Replace the battery ( Y page 76).
i If the key battery is checked within the
signal
reception range of the vehicle, press-
ing the & or % button:
R locks or
R unlocks the vehicle
i You can obtain a battery from any quali-
fied specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.76
Key
Opening and closing

Problem Possible causes/consequences and
M SolutionsThe engine cannot be
started using the key. 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 304).
or
X Jump-start the vehicle (Y page 308).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the key. The steering lock is mechanically blocked.
X
Remove the key 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 shift the manual transmission into neutral.
R start the engine.
There is a risk of an accident and injury.
When
leaving the vehicle, always take the key
with you and lock the vehicle. Never leave
children or animals unattended in the vehicle.
Always keep the key out of reach of children. G
WARNING
If persons (particularly children) are exposed
to heat or cold for a prolonged period, there
is

a risk of serious or even fatal injuries. Never
leave persons (particularly children) unatten-
ded in the vehicle.
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside.

People in the vehicle can no longer get
out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked with the key,
then the double lock function is activated as
standard. You can deactivate the double lock
function by deactivating the interior motion
sensor (Y page 70). The doors can then be
opened from the inside after the vehicle has
been locked from the outside. The anti-theft Doors
79
Opening and closing Z

You can only open the rear doors from inside
the vehicle if they are not secured by the
child-proof locks (Y page 60).
If
the vehicle has been locked using the lock-
ing 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.
You could therefore be locked out if:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is being tested on a dynamom-
eter.
You can also switch the automatic locking
function on and off using the on-board com-
puter ( Y page 223). Unlocking the driver's door (emer-
gency key element)
If

the vehicle can no longer be unlocked with
the key, use the emergency key element.
If you use the emergency key element to
unlock and open the driver's door, the anti-
theft alarm system will be triggered
(Y page 69).
X Take the emergency key element out of the
key ( Y page 75).
X Insert the emergency key element into the
lock

of the driver's door as far as it will go. X
Turn the emergency key element anti-
clockwise to position 1.
The door is unlocked.
i On right-hand-drive vehicles, turn the
emergency key element clockwise.
X Turn the emergency key element back and
remove it.
X Insert the emergency key element into the
key. Locking the vehicle (emergency key
element)
If

the vehicle can no longer be locked with the
key, use the emergency key element.
X Open the driver's door.
X Close the front-passenger door, the rear
doors and the tailgate.
X Press the locking button (Y page 80).
X Check whether the locking knobs on the
front-passenger door and the rear doors Doors
81
Opening and closing Z

Side window reversing feature
The side windows are equipped with an auto-
matic 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 to pay atten-
tion when closing a side window. G
WARNING
The reversing function does not react:
R to

soft, light and thin objects, e.g. small fin-
gers
R over the last 4 mm of the closing movement
R during resetting
R when closing the side window again man-
ually immediately after automatic reversing
This means that the reversing function cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
When closing make sure that no parts of the
body are in the closing area. If someone
becomes trapped, press the switch to open
the side window again. Opening and closing the side win-
dows
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 prec-
edence. :
Front left
; Front right
= Rear right
? Rear left
i The side windows cannot be operated
from

the rear when the override feature for
the side windows is activated ( Y page 61).
X Turn the key to position 1
or 2 in the ignition
lock.
X To open: press the corresponding switch.
X To open fully: press the corresponding
switch beyond the point of resistance.
Automatic closing is started.
X To close: pull the corresponding switch.
X To close fully: pull the corresponding
switch beyond the pressure point. Auto-
matic closing is started.
X To interrupt the automatic opening/
closing: press/pull the corresponding
switch again.
i If you press the switch beyond the point
of resistance, an automatic opening/clos-
ing

process is started in the corresponding
direction. You can stop automatic opera-
tion by pressing again.
i You can continue to operate the side win-
dows after switching off the engine or
removing the key. This function remains
active for five minutes or until the driver's
or front-passenger door is opened. 84
Side windows
Opening and closing

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 panorama sliding sunroof and the
roller sunblinds
i The convenience opening feature can
only be operated using the key. The key
must be close to the driver's door handle.
X Point the tip of the key at the driver's door
handle.
X Press and hold the % button until the
side windows and the panorama sunroof
are in the desired position.
If

the roller sunblinds of the panorama slid-
ing sunroof are closed, the roller sunblinds
are opened first.
X Press and hold the %
button again until
the panorama sliding sunroof is in the
desired position.
X To interrupt convenience opening:
release the % button.Convenience closing feature
G
WARNING
When the convenience closing feature is oper-
ating,
parts of the body could become trapped
in the closing area of the side window and the
sliding sunroof. There is a risk of injury.
Observe the complete closing procedure
when the convenience closing feature is oper-
ating. When closing make sure that no parts
of the body are in the closing area.
When you lock the vehicle, you can simulta-
neously:
R close the side windows
R close the panorama sliding sunroof
On vehicles with a panorama sliding sunroof,
you can then close the roller sunblinds. i
The
key must be close to the driver's door
handle.
X Point the tip of the key at the driver's door
handle.
X Press and hold the & button until the
side windows and the panorama sliding
sunroof are fully closed.
X Make sure that all the side windows and the
panorama sliding sunroof are closed.
On vehicles with a panorama sliding sunroof:
X Press and hold the &
button again until
the roller sunblinds of the panorama sliding
sunroof close.
X To interrupt convenience closing:
release the & button. Resetting the side windows
You must reset each side window if:
R the side window opens again slightly after
being closed fully.
R the side window can no longer be fully
opened or closed.
X Close all doors.
X Turn the key to position 1
or 2 in the ignition
lock.
X Pull the corresponding switch on the door
control

panel until the side window is com-
pletely closed ( Y page 84).
X Hold the switch for an additional second.
If the side window opens again slightly:
X Immediately pull the corresponding switch
on

the door control panel until the side win-
dow is completely closed (Y page 84).
X Hold the switch for an additional second.
X If 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 windows
85
Opening and closing Z

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 auto-
matic 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 to pay atten-
tion when closing the sliding sunroof. G
WARNING
The reversing function does not react:
R to

soft, light and thin objects, e.g. small fin-
gers
R over the last 4 mm of the closing movement
R during resetting
R when closing the sliding sunroof again man-
ually immediately after automatic reversing
This means that the reversing function cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
When closing make sure that no parts of the
body are in the closing area.
If someone is trapped:
R release the switch immediately or
R press the switch in any direction during the
automatic closing process
The closing process is stopped. Operating the sliding sunroof
Opening and closing Overhead control panel
:
To raise
; To open
= To close/lower
X Turn the key to position 1
or 2 in the ignition
lock.
X Press or pull the 3 switch in the corre-
sponding direction.
i If you press the 3 switch beyond the
point

of resistance, an automatic opening/
closing process is started in the corre-
sponding direction. You can stop automatic
operation by pressing again.
i After opening the sliding sunroof, the
roller sunblind closes slightly automati-
cally. This reduces drafts in the vehicle inte-
rior.
i If the sliding sunroof is raised at the rear,
it lowers slightly automatically at higher
speeds. The noise level in the vehicle inte-
rior is reduced as a result.
At low speeds it raises again automatically.
i You can continue to operate the sliding
sunroof after switching off the engine or
removing the key. This function remains
active for five minutes or until you open a
front door.
i The sliding sunroof cannot be opened if a
roof carrier is fitted. In order to allow ven- Panorama sliding sunroof
87
Opening and closing Z