2012 MERCEDES-BENZ A CLASS battery

Problem Possible causes/consequences and
M SolutionsThe 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 P or 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 P and
the transmission position display must
show P in 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 N when 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
Parking
Driving and parking

Releasing
X
Pull handle :.
The red ! indicator lamp in the instru-
ment cluster goes out.
i You can only release the electric parking
brake when the key is in position 1 or 2 in
the ignition lock.
Applying automatically The electric parking brake is applied auto-
matically:
R
if DISTRONIC PLUS brings the vehicle to a
standstill (vehicles with automatic trans-
mission) or
R if
the HOLD function is keeping the vehicle
stationary.
In addition, at least one of the following con-
ditions must be fulfilled:
R the engine is switched off
R the driver's door is open and the seat belt
is not fastened
R there is a system malfunction
R the power supply is insufficient
R the vehicle is stationary for a lengthy
period.
The red ! indicator lamp in the instrument
cluster lights up.
i The electric parking brake is not automat-
ically applied if the engine is switched off
by the ECO start/stop function.
Releasing automatically i
The electric parking brake can only be
released automatically in vehicles with
automatic transmission.
The electric parking brake of your vehicle is
released

automatically when all of the follow-
ing conditions are fulfilled:
R the engine is running.
R the transmission is in position D or R.
R the seat belt is fastened.
R you depress the accelerator pedal. If the transmission is in position
R,
the tailgate
must be closed.
If your seat belt is not fastened, the following
conditions must be fulfilled to automatically
release the electric parking brake:
R the driver's door is closed.
R you have shifted out of transmission posi-
tion P or you have previously driven faster
than 3 km/h.
Emergency braking The vehicle can also be braked during an
emergency using the electric parking brake.
X
While driving, push handle :
of the electric
parking brake ( Y page 163).
i The vehicle is braked for as long as han-
dle : of the electric parking brake
pressed. The longer the electric parking
brake handle : is depressed, the greater
the braking force.
During braking:
R a warning tone sounds
R the Release parking brake message
appears
R the red ! indicator lamp in the instru-
ment cluster flashes
When

the vehicle has been braked to a stand-
still, the electric parking brake is engaged. Parking up the vehicle
If you leave the vehicle parked up for longer
than

four weeks, the battery may be damaged
by exhaustive discharging.
If you leave the vehicle parked up for longer
than six weeks, the vehicle may suffer dam-
age as a result of lack of use.
X Visit a qualified specialist workshop and
seek advice.
i You can obtain information about trickle
chargers from a qualified specialist work-
shop. 164
Parking
Driving and 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
179
Driving and parking Z

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.
The trailer battery may not be charged from
the power supply.
X To switch the connected power supply
on or off: turn the key in the ignition lock
to position 2 or 0 respectively.
When it leaves the factory, your vehicle's
trailer socket is equipped with a permanent
power supply and a power supply that is
switched on via the ignition lock.
The permanent power supply is supplied via
trailer socket pin 9.
The power supply that is switched on via the
ignition lock is supplied via trailer socket pin
10.
The trailer's permanent power supply is
switched

off in the event of low vehicle supply
voltage and after six hours at the latest.
You can find more information about instal-
ling the trailer electrics at a qualified special-
ist workshop. Bulb failure indicator for LED lamps
i If LED lamps are fitted in the trailer, an
error message may appear in the multi-
function

display even if there is no fault. The
reason for the error message could be that
the current has fallen below the minimum
of 50 mA. To ensure reliable operation of the bulb failure
indicator,

each LED chain in the trailer lighting
must be guaranteed a minimum current of
50 mA. Trailer with 7-pin connector
General notes Trailer with 7-pin connector: you can con-
nect

to the 13-pin socket on the ball coupling
using an adapter or, if necessary, an adapter
cable. Both can be obtained at a qualified
specialist workshop.
Fitting the adapter !
Make sure that there is sufficient cable
play so that the cable cannot become
detached when cornering.
! 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
Open the socket cover.
X Insert the plug connector with lug : into
groove =

on the socket. Turn bayonet con-
nection ; clockwise to the stop.
X Let the cover engage.
X If you are using an adapter cable, secure
the cable to the trailer with cable ties.206
Towing a trailer
Driving and parking

Flammable material such as leaves, grass or
twigs
may ignite if they come into contact with
hot parts of the exhaust system for extended
periods. There is a risk of fire.
When the auxiliary heating is switched on,
make sure that no flammable material can
come into contact with hot vehicle compo-
nents.
! Operating the auxiliary heating/ventila-
tion draws on the vehicle battery. After you
have heated or ventilated the vehicle a
maximum of two times, drive for a longer
distance.
i Switch the auxiliary heating on regularly
once a month for about ten minutes.
Comfort Switching belt adjustment on/off
X
Press the =
or ; button on the steer-
ing wheel to select the Settings menu.
X Press the :
or 9 button to select the
Convenience submenu.
X Press a to confirm.
X Press the :
or 9 button to select the
Belt adjustment function.
If the Belt adjustment function is activa-
ted, the vehicle seat belt is shown in orange
in the multifunction display.
X Press the a button to save the setting.
For further information on belt adjustment,
see ( Y page 47).
Switching the fold in mirrors when lock-
ing function on/off
This

function is only available on vehicles with
a memory function (Y page 101).
When you activate the Auto. fold-in mir‐
rors function, the exterior mirrors are folded
in when the vehicle is locked.
When you unlock the vehicle and then open a
door, the exterior mirrors fold out again.
If you have switched on the Auto. fold-in
mirrors function and you fold in the exterior mirrors using the button on the door
(Y page 99), they will not fold out automati-
cally. The exterior mirrors can then only be
folded out using the button on the door.
X
Press the =
or ; button on the steer-
ing wheel to select the Settings menu.
X Press the :
or 9 button to select the
Convenience submenu.
X Press a to confirm.
X Press the :
or 9 button to select the
Auto. fold-in mirrors function.
If the Auto. fold-in mirrors function is
activated, the vehicle's exterior mirror is
displayed in orange in the multifunction
display.
X Press the a button to save the setting.
Resetting to factory settings X
Press the =
or ; button on the steer-
ing wheel to select the Settings menu.
X Press the :
or 9 button to select the
Factory setting submenu.
X Press a to confirm.
The Reset all settings? message
appears.
X Press the : or 9 button to select
No or Yes.
X Press the a
button to confirm the selec-
tion.
If you have selected Yes , the multifunction
display shows a confirmation message.
For safety reasons, not all functions are reset:
the Limit speed (winter tyres): func-
tion

in permanent SPEEDTRONIC can only be
set in the VEHICLE submenu. If you want to
reset the Daytime driving lights: in the
Light submenu, you must turn the key in the
ignition lock to position 1. Menus and submenus
225
On-board computer and displays Z

Display messages Possible causes/consequences and
M SolutionsThe yellow
! warning lamp lights up. If you manually apply or
release the electric parking brake, the red ! indicator lamp
flashes.
The electric parking brake is malfunctioning. It is not possible to
apply the electric parking brake manually.
X Vehicles with manual transmission: engage first gear.
X Vehicles with automatic transmission: shift the transmission
to P.
X Visit a qualified specialist workshop. !
Parking

brake inop‐
erative The yellow
! warning lamp lights up. The red ! indicator
lamp flashes for about ten seconds after the electric parking brake
has been applied or released. It then goes out or remains lit.
The electric parking brake is malfunctioning, e.g. because of over-
voltage or undervoltage.
X Rectify the cause of the overvoltage or undervoltage, e.g. by
charging the battery or restarting the engine.
X Apply or release the electric parking brake.
If it remains impossible to apply or release the electric parking
brake:
X Switch off the ignition and turn it back on.
X Apply or release the electric parking brake.
If the electric parking brake still cannot be released:
X Consult a qualified specialist workshop. The display message is only shown while the vehicle is in motion.
The

red ! indicator lamp flashes and the yellow ! warning
lamp is lit.
It is not possible to apply the electric parking brake manually.
X Vehicles with manual transmission: engage first gear.
X Vehicles with automatic transmission:
shift the transmission
to P.
X Visit a qualified specialist workshop. !
Turn on the igni‐
tion to release
the parking brake The red
! indicator lamp lights up.
You
attempted to release the electric parking brake while the igni-
tion was switched off.
X Turn the key to position 1 in the ignition lock. Display messages
235
On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions?
Coolant Stop vehi‐
cle Switch engine
off The coolant is too hot.
A warning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam
from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away ( Y page 162).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the display message goes out
and the coolant temperature is below

120 †. The engine may
otherwise be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to
120 †.# The battery is not being charged.
A warning tone also sounds.
Possible causes:
R
faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Open the bonnet.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do

not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is OK:
X Visit a qualified specialist workshop immediately.244
Display messages
On-board computer and displays

Vehicle
Display messages Possible causes/consequences and
M SolutionsTo start engine,
shift to either P
or N You have attempted to start the engine with the transmission in
position R or D.
X
Shift the transmission to position P or N.Auxiliary battery
malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X
Visit a qualified specialist workshop at the next opportunity.
X Until then, set the automatic transmission to position P before
you switch off the engine.
X Before leaving the vehicle, apply the electric parking brake. Depress brake to
start engine You have attempted to start the engine with the transmission in
position N without depressing the brake pedal.
X
Depress the brake pedal. To shift out of P
or N
depress brake and
start engine You have attempted to shift the transmission to position
R or D
without starting the engine.
X Start the engine.
X Depress the brake pedal.
i It is only possible to shift the transmission from position P to
the desired position if you depress the brake pedal. Only then
can the parking lock be deactivated. If you do not depress the
brake pedal, the DIRECT SELECT lever can still be moved but
the parking lock remains engaged.
i At
transmission fluid temperatures below Ò20 † you can only
shift out of position P into another transmission position when
the engine is running. Apply brake to
deselect Park (P)
position You have attempted to move the transmission selector lever to
position R, N or D without depressing the brake pedal.
X
Depress the brake pedal. Risk of vehicle
rolling
Transmission not
in P The driver's door is open and the transmission is in position
R, N
or D.
A warning tone also sounds.
X Shift the transmission to position P.
X Secure the vehicle against rolling away ( Y page 162).252
Display messages
On-board computer and displays