ignition MERCEDES-BENZ A-CLASS HATCHBACK 2015 User Guide

R
a vehicle travelling in front on a different
line
R new vehicles or after a service on the COL-
LISION PREVENTION ASSIST PLUS system
Observe the important safety notes in the
"Running-in notes" section (Y page 156).
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at slow speeds where there is no visible
damage to the front of the vehicle.
Activating/deactivating The COLLISION PREVENTION ASSIST PLUS is
automatically active after switching on the
ignition.
You can activate or deactivate COLLISION
PREVENTION ASSIST PLUS in the on-board
computer (Y page 249). When deactivated,
the distance warning function and the auton- omous braking function are also deactivated.
Vehicles with black and white multifunc-
tion display: when COLLISION PREVENTION
ASSIST PLUS is activated, the multifunction
display in the status overview shows the Ä
symbol.
Vehicles with colour multifunction dis-
play: when COLLISION PREVENTION ASSIST
PLUS is deactivated, the multifunction dis-
play in the assistance graphic shows the æ
symbol.
Distance warning function General notes
The distance warning function can help you to
minimise the risk of a collision with the vehi-
cle in front or reduce the effects of such a
collision. If the distance warning function
detects that there is a risk of a collision, you
will be warned visually and acoustically. Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 69). G
WARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
Thus, the distance warning function cannot
provide a warning in all critical situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. G
WARNING
The distance warning function cannot always
clearly identify objects and complex traffic
situations.
In such cases, the distance warning function
may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation; do not rely on the distance warning
function alone.
Function
The distance warning function issues a warn- ing at speeds:
R of approximately 30 km/h or more, if, over
several seconds, the distance maintained
to the vehicle travelling in front is insuffi-
cient. The ·distance warning lamp
then lights up in the instrument cluster.
R of approximately 7 km/h or more, if you
rapidly approach a vehicle in front. An inter-
mittent warning tone will then sound, and
the · distance warning lamp will light
up in the instrument cluster. Driving safety systems
71Safety Z

ESP
®
trailer stabilisation does not work if
ESP ®
is deactivated or disabled because of a
malfunction. EBD (electronic brake force distribu-
tion)
General notes EBD monitors and controls the brake pres-
sure on the rear wheels to improve driving
stability while braking.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 69). G
WARNING
If EBD is malfunctioning, the rear wheels can
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 spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (Y page 295) as well as dis-
play messages (Y page 260). ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In addi- tion to the braking function, ADAPTIVE BRAKE
also has the HOLD function (Y page 204)and
hill start assist (Y page 161). STEER CONTROL
General notes STEER CONTROL helps you by transmitting a
noticeable steering force to the steering
wheel in the direction required for vehicle
stabilisation. This steering support 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
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 69).
No steering support is provided from STEER
CONTROL, if:
R ESP ®
is malfunctioning
R the steering is faulty
If ESP ®
is malfunctioning, you will be assisted
further by the electrical power steering. Protection against theft
Immobiliser
The immobiliser prevents your vehicle from
being started without the correct key.
X To activate with the key: remove the key
from the ignition lock.
X To activate with KEYLESS-GO start func-
tion or KEYLESS-GO: switch the ignition
off and open the driver's door.
X To deactivate: switch on the ignition.
When leaving the vehicle, always take the key with you and lock the vehicle. Anyone can
start the engine if a valid key has been left
inside the vehicle.
i The immobiliser is always deactivated
when you start the engine. Protection against theft
77Safety Z

ATA (Anti-Theft Alarm system)
X
To prime: lock the vehicle with the key or
KEYLESS-GO.
Indicator lamp :flashes. The alarm sys-
tem is primed after approximately
15 seconds.
X To deactivate: unlock the vehicle with the
key or KEYLESS-GO.
or X Insert the key into the ignition lock.
A visual and audible alarm is triggered if the
alarm system is primed and you open:
R a door
R the vehicle with the emergency key ele-
ment
R the tailgate
R the bonnet
X To switch the alarm off with the key:
press the %or& button on the key.
The alarm is deactivated.
or X Vehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: remove the Start/
Stop button from the ignition lock
(Y page 157).
X Insert the key into the ignition lock.
The alarm is deactivated. X
To deactivate the alarm using KEYLESS-
GO: grasp the outside door handle. The key
must be outside the vehicle.
The alarm is deactivated.
or
X Press the Start/Stop button on the dash-
board. The key must be inside the vehicle.
The alarm is deactivated.
The alarm is not switched off, even if you
close the open door that has triggered it, for
example.
i If the alarm stays on for more than
30 seconds, the Mercedes‑Benz emer-
gency call system automatically sends a
message to the Customer Assistance
Centre. This is done by means of a text
message or a data connection.
The emergency call system sends a mes-
sage or establishes a data connection pro-
vided that:
R you have subscribed to the
Mercedes‑ Benz emergency call system
R the Mercedes‑Benz emergency call sys-
tem has been activated properly
R the necessary mobile phone network is
available Tow-away protection
Function An audible and visual alarm is triggered if your
vehicle's angle of inclination is altered while
tow-away protection is primed. This can occur if the vehicle is jacked up on one side, for
example.
Activating X
Make sure that: 78
Protection against theftSafety

R
the doors are closed
R the tailgate is closed
Only then is tow-away protection primed.
X Lock the vehicle with the key or KEYLESS-
GO.
Tow-away protection is primed after
approximately 60 second s.
Switching off X
Unlo ck the vehicle with the key or KEY-
LESS-GO.
or X Insert the key into the ignition lock.
Tow-away protection is switched off auto-
matically.
Deactivating X
Remove the key from the ignition lock.
or X Vehicles with KEYLESS-GO start func-
tion or KEYLESS-GO: switch off the engine
using the Start/Stop button and open the
driver's door.
X Press button :.
Indicator lamp ;lights up briefly.
X Lock the vehicle with the key or KEYLESS-
GO.
Tow-away protection is deactivated.
Tow-away protection remains deactivated
until:
R the vehicle is unlocked again
R a door is opened and closed again and
R the vehicle is locked again To prevent a false alarm, deactivate tow-away
protection if you lock your vehicle and it:
R is being transported
R is being loaded onto a ferry or car trans-
porter, for example
R is parked on a movable surface, e.g. in a
split-level garage Interior motion sensor
Function When the interior motion sensor is primed, a
visual and audible alarm is triggered if move-
ment is detected in the vehicle interior. This
can occur if someone reaches into the vehicle interior, for example.
Activating X
Make sure that:
R the side windows are closed
R the panorama sliding sunroof is closed
R there are no objects, e.g. mascots, hang-
ing on the rear-view mirror or on the grab handles on the roof trim
This will prevent false alarms.
X Make sure that:
R the doors are closed
R the panorama sliding sunroof is closed
R the tailgate is closed
Only then is the interior motion sensor
primed.
X Lock the vehicle with the key or KEYLESS-
GO.
The interior motion sensor is primed after
approximately 30 seconds.
Switching off X
Unlock the vehicle with the key or KEY-
LESS-GO.
or X Insert the key into the ignition lock. Protection against theft
79Safety Z

or
X Press the Start/Stop button.
The key must be in the vehicle.
The interior motion sensor is automatically
switched off.
Deactivating X
Remove the key from the ignition lock.
or X Vehicles with KEYLESS-GO start func-
tion or KEYLESS-GO: switch off the engine
using the Start/Stop button and open the
driver's door.
X Press button :.
Indicator lamp ;flashes several times in
rapid succession.
X Lock the vehicle with the key or KEYLESS-
GO.
The interior motion sensor is deactivated.
The interior motion sensor remains deactiva- ted until:
R the vehicle is unlocked again and
R a door is opened and closed again and
R the vehicle is locked again
To prevent a false alarm, deactivate the inte-
rior motion sensor if you lock your vehicle
and:
R people or animals remain in the vehicle
R the panorama sliding sunroof remains open
R the side windows remain open
i UK only:
your vehicle is equipped with a
double-lock function. The doors cannot be opened from the inside if the vehicle has
been locked with the key (Y page 89).
Deactivate the interior motion sensor
before you lock the vehicle with the key.
The doors can then be opened from the
inside after the vehicle has been locked
from the outside with the key. Observe the
"Important safety notes" (Y page 89).80
Protection against theftSafety

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 doors, thereby endangering other per-
sons or road users
R get out and be struck by oncoming traffic
R operate vehicle equipment and become
trapped, for example
In addition, the children could also set the
vehicle in motion, for example, if they:
R release the parking brake
R shift the automatic transmission out of park
position P or shift 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 and animals unattended in the vehi-
cle. Keep the keys out of the reach of children. 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 insert-
ing 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
Vehicles with KEYLESS-GO start function: do not keep the key in the luggage compart-
ment. Otherwise, the key may not be detec-
ted, e.g. when starting the engine using the
Start/Stop button.
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 from the out-
side, the double lock function is activated as
standard. It is then not possible to open the
doors from inside the vehicle. You can deac-
tivate the double lock function by deactivat-
ing the interior motion sensor (Y page 80).
The doors can then be opened from the inside after the vehicle has been locked from the
outside. You can open the rear doors from
inside the vehicle if they are not secured by
the child-proof locks (Y page 68). The anti-
theft alarm system is triggered if the door is 82
KeyOpening and closing

X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor sur-
face :or;.
Make sure that you do not touch the inner
surface of the door handle.
X Convenience closing feature: touch
recessed sensor surface ;for an exten-
ded period.
For further information on the convenience closing feature (Y page 95).X
To unlock the tailgate: pull tailgate han-
dle :.
Deactivating and activating If you do not intend to use the vehicle for an
extended period of time, you can deactivate
KEYLESS-GO. The key will then use very little power, thereby conserving battery power. For
the purposes of activation or deactivation,
the vehicle does not have to be nearby. X
To deactivate: press the&button on
the key twice in rapid succession.
The battery check lamp of the key flashes
twice briefly and lights up once, then KEY-
LESS-GO is deactivated (Y page 86).
X To activate: press any button on the key.
or
X Insert the key into the ignition lock.
KEYLESS-GO and all of its associated fea-
tures are available again. KEYLESS-GO start function
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a key
in the vehicle. 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 alone.
X To change the setting: press and hold
down the %and& buttons simulta-
neously for about six seconds until the bat-
tery indicator lamp flashes twice
(Y page 86).
If the setting of the locking system is changed
within the signal range of the vehicle, press-
ing the &or% button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock: press the%button once.
X To unlock centrally: press the%but-
ton twice.
X To lock centrally: press the&button. 84
KeyOpening and closing

The KEYLESS-GO function is changed as fol-
lows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner sur-
face of the door handle on the front-
passenger door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
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 86). Emergency key element
General notes If the vehicle can no longer be unlocked with
the key or KEYLESS-GO, use the emergency
key element.
If you use the emergency key element to
unlock and open the driver's door or the tail-
gate, the anti-theft alarm system will be trig-
gered (Y page 78).
There are several ways to deactivate the
alarm:
X To deactivate the alarm with the key:
press the %or& button on the key.
or X Insert the key into the ignition lock.
or
X To deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the igni-
tion lock. The key must be in the vehicle.
or X Lock or unlock the vehicle using KEYLESS-
GO. The key must be outside the vehicle.
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.
Further information about:
R unlocking the driver's door (Y page 91)
R unlocking the luggage compartment
(Y page 93)
R locking the vehicle (Y page 92)
Inserting the emergency key element X
Push emergency key element ;com-
pletely into the key until it engages and
release catch :is back in its basic posi-
tion. 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. Key
85Opening and closing Z

Problem
Possible causes/consequences and
M
MSolutions There is a fault with KEYLESS-GO.
X Lock/unlock the vehicle using the remote control function of
the key.
X Have the vehicle and key checked at a qualified specialist work-
shop.
If the vehicle can also not be locked/unlocked using the remote
control function:
X Lock (Y page 91) or unlock (Y page 92) the vehicle using the
emergency key element.
X Have the vehicle and key checked at a qualified specialist work-
shop. The 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 347).
or
X Jump-start the vehicle (Y page 348).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The key is
in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The key battery is discharged or nearly discharged.
X Check the key battery (Y page 86) and replace it if necessary
(Y page 86).
If this does not work: X Start your vehicle with the key in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the key in the ignition lock. 88
KeyOpening and closing

vehicle. You can deactivate the double lock
function by deactivating the interior motion
sensor (Y page 80). The doors can then be
opened from the inside after the vehicle has
been locked from the outside. You can open
the rear doors from inside the vehicle if they
are not secured by the child-proof locks
(Y page 68). The anti-theft alarm system is
triggered if the door is opened from the
inside. Switch off the alarm (Y page 78).
When a locked door is opened from inside the vehicle, the previous unlocking process will
be observed if the vehicle has been:
R locked with the locking button for the cen-
tral locking or
R locked automatically
The vehicle will be fully unlocked if it had pre- viously been fully unlocked. Only the door
which has been opened from 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 approximately five seconds until a tone sounds.
X To activate: press and hold button ;for
approximately five seconds until a tone
sounds.
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 activate and deactivate the auto- matic locking function using the on-board
computer (Y page 251). Unlocking the driver's door (emer-
gency key element)
If the vehicle can no longer be unlocked with
the key or KEYLESS-GO, 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 78).
X Take the emergency key element out of the
key (Y page 85).
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 as far as it will go to position 1. Doors
91Opening and closing Z