2012 MERCEDES-BENZ A-CLASS HATCHBACK ECU

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). Running-in notes
Important safety notes
New brake pads/linings and discs that have
been replaced only achieve optimum braking effect after several hundred kilometres of
driving. Compensate for the reduced braking
effect by applying greater force to the brake
pedal. The first 1500 km
If you treat the engine with sufficient care
from the very start, you will be rewarded with excellent performance for the remainder of
the engine's life.
R Drive at varying vehicle speeds and engine
speeds for the first 1500 km.
R Avoid overstraining the vehicle during this
period, e.g. driving at full throttle.
R Change gear in good time, before the rev
counter needle is Ôof the way to the red
area of the rev counter.
R Do not shift down a gear manually in order
to brake.
Vehicles with automatic transmission:
R Try to avoid depressing the accelerator
pedal beyond the point of resistance (kick-
down).
After 1,500 km, you may gradually bring the
vehicle up to full road and engine speeds. Additional running-in notes for AMG vehicles:
R Do not drive at speeds above 140 km/ hfor
the first 1,500 km.
R Only allow the engine to reach a maximum
engine speed of 4,500 rpm briefly.
i You should also observe these notes on
running-in if the engine or parts of the drive train on your vehicle have been replaced. Driving
Important safety notes
G
WARNING
Objects in the driver's footwell may restrict
the clearance around the pedals or block a
depressed pedal. This jeopardises the oper-
ating and road safety of the vehicle. There is a risk of an accident.
Stow all objects securely in the vehicle so that
they do not get into the driver's footwell.
Always fit the floormats securely and as pre-
scribed in order to ensure that there is always sufficient room for the pedals. Do not use
loose floormats and do not place several floor-mats on top of one another. G
WARNING
Unsuitable footwear can hinder correct usage of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably 142
DrivingDriving and parking

Important safety notes
G
WARNING
If the engine is switched off automatically and you exit the vehicle, the engine is restarted
automatically. The vehicle may begin moving. There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes :
ECO start/stop display
If the ¤ symbol is shown in green in the
multifunction display, the ECO start/stop
function switches the engine off automati-
cally if the vehicle stops moving.
The stop/start function is automatically acti-
vated each time you start the engine with the ignition key.
If the ECO start/stop function has been man- ually deactivated (Y page 147) or a malfunc-
tion has caused the system to be deactivated, the ¤ symbol is not displayed.
AMG vehicles: the ECO start/stop function
is only available in drive program C.
Automatic engine switch-off General notes
The ECO start/stop function is operational
and the
¤symbol is displayed in green in
the multifunction display, if:
R the indicator lamp in the ECO button is lit
green
R the outside temperature is within the range
that is suitable for the system R
the engine is at normal operating temper-
ature
R the set temperature for the vehicle interior
has been reached
R the battery is sufficiently charged
R the system detects that the windscreen is
not misted up when the air-conditioning
system is switched on
R the bonnet is closed
R the driver's door is closed and the driver's
seat belt is fastened
If not all conditions for automatic engine
switch-off are fulfilled, the ¤symbol is
shown in yellow.
i All of the vehicle's systems remain active
when the engine is switched off automati-
cally.
i The engine can be switched off automat-
ically a maximum of four times (initial stop,
then three subsequent stops) in succes-
sion. The ¤symbol is shown in yellow in
the multifunction display after the engine
has been started automatically for the
fourth time. When the ¤symbol is
shown in green in the multifunction display,
automatic engine switch-off is again possi-
ble.
Vehicles with manual transmission
The ECO start/stop function switches off the engine automatically at low speeds. X
Brake the vehicle.
X Engage neutral N(Ypage 151) (follow
gearshift instruction :to engage neutral
N, if necessary).
X Release the clutch pedal.
The engine is switched off automatically. 146
DrivingDriving and pa
rking

Problem
Possible causes/consequences and
M
MSolutions The fuel filler flap can-
not be opened. The fuel filler flap is not unlocked.
or
The key battery is discharged.
X Unlock the vehicle (Y page 75).
or
X Unlock the vehicle using the emergency key element
(Y page 75). The fuel filler flap is unlocked, but the opening mechanism is jam-
med.
X Consult a qualified specialist workshop. Parking
Important safety notes
G
WARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with hot parts of the exhaust system or exhaust
gas flow. There is a risk of fire.
Park the vehicle so that no flammable mate-
rial can come into contact with hot vehicle
components. In particular, do not park on dry grassland or harvested grain fields. G
WARNING
If you leave children unattended in the vehi-
cle, they may be able to set the vehicle in
motion if, for example, they:
R release the parking brake
R shift the automatic transmission out of park
position Por shift manual transmission into
neutral
R start the engine
In addition, they may operate vehicle equip-
ment and become trapped. 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 unattended in the vehicle. !
Always secure the vehicle correctly
against rolling away. Otherwise, the vehicle
or its drivetrain could be damaged.
To ensure that the vehicle is secured against
rolling away unintentionally:
R the electric parking brake must be applied.
R on vehicles with manual transmission,
engage first gear or reverse gear.
R on vehicles with automatic transmission,
the transmission must be in position Pand
the transmission position display must
show Pin the multifunction display.
R the key must be removed from the ignition
lock.
R on uphill or downhill gradients, the front
wheels must be turned towards the kerb. Switching off the engine
Important safety notes G
WARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-162
ParkingDriving and parking

DISTRONIC PLUS is automatically deactiva-
ted if:
R you apply the electric parking brake or if the
vehicle is automatically secured with the
electric parking brake
R you are driving slower than 10 km/h and
there is no longer a vehicle in front, or if the vehicle in front is no longer detected
R ESP ®
intervenes or you deactivate ESP ®
R the transmission is in the P,Ror Nposition
R you switch off the radar sensor system
R you pull the cruise control lever towards
you in order to pull away and the front-
passenger door or one of the rear doors is
open
R the vehicle is skidding
R you activate Active Parking Assist
If DISTRONIC PLUS is deactivated, you will
hear a warning tone. You will see the DIS‐
DIS‐
TRONIC TRONIC PLUS
PLUSoff
offmessage in the multifunc-
tion display for approximately five seconds.
In the Assistance menu (Y page 217) of the
on-board computer, you can select the assis-
tance graphic. :
Vehicle in front, if detected
; Distance indicator: current distance to
the vehicle in front
= Specified minimum distance to the vehi-
cle in front; adjustable
? Own vehicle
X Select the Distance display
Distance display function
using the on-board computer
(Y page 217). Tips for driving with DISTRONIC PLUS General notes
The following contains descriptions of certain
road and traffic conditions in which you must be particularly attentive. In such situations,
brake if necessary. DISTRONIC PLUS is then
deactivated.
Cornering, going into and coming out of a
bend The ability of DISTRONIC PLUS to detect vehi-
cles when cornering is limited. Your vehicle
may brake unexpectedly or late.
Vehicles which are not driving in the mid- dle of their lane DISTRONIC PLUS may not detect vehicles
which are not driving in the middle of their
lane. The distance to the vehicle in front will
be too short.178
Driving systemsDriving an
d parking

Other vehicles changing lane
DISTRONIC PLUS has not detected the vehi-
cle cutting in yet. The distance to this vehicle will be too short.
Narrow vehicles DISTRONIC PLUS has not yet detected the
vehicle in front on the edge of the carriage-
way, because of its narrow width. The dis-
tance to the vehicle in front will be too short.
Obstructions and stationary vehicles DISTRONIC PLUS does not brake for obsta-
cles or stationary vehicles. If, for example, the detected vehicle turns a corner and reveals
an obstacle or stationary vehicle, DISTRONIC
PLUS will not brake for these.
Crossing vehicles DISTRONIC PLUS may detect vehicles that
are crossing your lane by mistake. Activating
DISTRONIC PLUS at traffic lights with cross-
ing traffic, for example, could cause your vehi-
cle to pull away unintentionally. HOLD function
Important safety notes G
WARNING
When leaving the vehicle, it can still roll away despite being braked by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply
R the HOLD function is deactivated by the
accelerator pedal being depressed, e.g. by
a vehicle occupant
R the electrical system in the engine com-
partment, the battery or the fuses are tam-
pered with
R the battery is disconnected
There is a risk of an accident.
Before leaving the vehicle, always deactivate
the HOLD function and secure the vehicle
from rolling away. Driving systems
179Driving and parking Z

!
If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations. To prevent dam-
age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow-
ing or other similar situations:
R when towing the vehicle
R in the car wash
Deactivate the HOLD function (Y page 180).
General notes The HOLD function can assist the driver in the
following situations:
R when pulling away, especially on steep
slopes
R when manoeuvring on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect is cancelled and the HOLD function is deactivated when you depress theaccelerator pedal to pull away.
Activation conditions You can activate the HOLD function if:
R the vehicle is stationary
R the engine is running or if it has been auto-
matically switched off by the ECO start/
stop function
R the driver's door is closed or if your seat
belt is fastened
R the electric parking brake is released
R the transmission is in position D,Ror Non
vehicles with automatic transmission
R DISTRONIC PLUS is deactivated Activating the HOLD function Example: vehicles with colour multifunction display
X Make sure that the activation conditions
are met.
X Depress the brake pedal.
X Quickly depress the brake pedal further
until :appears in the multifunction dis-
play.
The HOLD function is activated. You can
release the brake pedal.
i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.
Deactivating the HOLD function The HOLD function is deactivated automati-
cally if:
R you accelerate. On vehicles with automatic
transmission: only when the transmission
is in position Dor R.
R the transmission is in position Pon vehicles
with automatic transmission.
R you depress the brake pedal again with a
certain amount of pressure until :disap-
pears from the multifunction display.
R you secure the vehicle using the electric
parking brake.
R you activate DISTRONIC PLUS.
i After a short period the vehicle is secured
by the electric parking brake, thus relieving
the service brake. 180
Driving systemsDriving and parking

The electric parking brake secures the vehicle
automatically if the HOLD function is activa-
ted and:
R the driver's door is open and the driver's
seat belt is unfastened
R the engine is switched off, unless it is auto-
matically switched off by the ECO start/
stop function
R a system fault occurs
R the power supply is not sufficient
Vehicles with automatic transmission
If a fault occurs, then the transmission may
also be shifted into position Pautomatically.
Vehicles with manual transmission
The Brake immediately Brake immediately message can also
appear in the multifunction display.
X Immediately depress the brake pedal firmly
until the warning message in the multifunc- tion display goes out.
The HOLD function is deactivated.
A horn will sound at regular intervals if you
turn off the engine, take off your seat belt or
open the driver's door when the HOLD func-
tion is activated. The horn alerts you to the
fact that the HOLD function is still activated.
If you attempt to lock the vehicle, the tone
becomes louder. The vehicle cannot be
locked until you have deactivated the HOLD
function.
i Once you have switched off the engine,
you cannot restart it until you have deacti-
vated the HOLD function. RACE START
Important safety notes RACE START enables optimum acceleration
from a standing start. The precondition for
this is a suitable high-grip road surface.
Only activate RACE START on dedicated race
circuits. i
RACE START is only available in AMG vehi-
cles.
Activation conditions You can activate RACE START if:
R the doors, the bonnet and the tailgate are
closed
R the engine is running and the transmission,
traction control and engine are at operating
temperature
R SPORT handling mode is activated
(Y page 66)
R the steering wheel is in the straight-ahead
position.
R the vehicle is stationary and the brake
pedal is depressed (left foot)
R the transmission is in position D.
R drive program Mis selected (Y page 155).
Activating RACE START X
Depress the brake pedal with your left foot
and keep it depressed.
X Pull and hold both steering wheel gearshift
paddles.
X The RACE START Confirm: Paddle UP RACE START Confirm: Paddle UP
Cancel: Paddle DOWN
Cancel: Paddle DOWN message appears
in the multifunction display.
X Release both steering wheel gearshift pad-
dles.
i If the activation conditions are no longer
fulfilled, RACE START is cancelled. The
RACE START not possible See Own‐
RACE START not possible See Own‐
er's er's Manual
Manual message appears in the mul-
tifunction display.
X To cancel: pull the left steering wheel shift
paddle (Y page 156).
or
X To confirm: pull the right steering wheel
shift paddle (Y page 156).
The RACE START available Depress
RACE START available Depress
accelerator
accelerator message appears in the mul-
tifunction display. Driving systems
181Driving and parking Z

!
Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the rebound- ing of the overrun brake.
! Remove the installed adapter cable
before folding in the ball coupling. Other-
wise, damage may occur to the rear
bumper and the adapter cable.
X Make sure that the transmission is in posi-
tion P.
X Apply the electric parking brake.
X Secure the trailer against rolling away.
X Remove the trailer cable and decouple the
trailer. Folding in the ball coupling
G
WARNING
If you release the ball coupling or it does not
engage correctly when folding in, it will swing out. Within pivoting range of the ball coupling,
there is an increased risk of an accident and
injury.
Only release the ball coupling if the pivoting
range is unobstructed. Always make sure that the ball coupling engages when folding in.
X Fold the ball coupling back in if you are not
using the trailer tow hitch.
X Place the protective covering on the ball
coupling.
The release wheel is located behind the left-
hand side trim panel in the boot. X
To open the cover: turn handle:anti-
clockwise and fold down cover ;and
remove it. X
Pull out release wheel =.
X Turn release wheel =anti-clockwise as far
as it will go.
The ball coupling disengages and folds out
behind the rear bumper. Indicator lamp ?
flashes. X
Press the ball coupling in the direction of
the arrow until it engages behind the
bumper.
Indicator lamp ?goes out and the mes-
sage in the multifunction display disap-
pears. Trailer power supply
! You can connect accessories with a
power rating of up to 240 W to the perma-
nent power supply and with a power rating of up to 180 W to the power supply that is
switched on via the ignition lock. Towing a trailer
205Driving and parking Z