ignition MERCEDES-BENZ A-CLASS HATCHBACK 2012 Workshop Manual

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

Problems with the engine
Problem
Possible causes/consequences and
M
MSolutions The engine does not
start. The HOLD function or DISTRONIC PLUS is activated.
X Deactivate the HOLD function (Y page 179) or DISTRONIC
PLUS (Y page 173).
X Try to start the engine again. The engine does not
start. The starter motor
can be heard. R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
X Turn the key back to position 0in the ignition lock before
attempting to start the engine again.
X Try to start the engine again (Y page 143). Avoid excessively
long and frequent attempts to start the engine, as this will drain the battery.
If the engine does not start after several attempts:
X Consult a qualified specialist workshop. The engine does not
start. The starter motor
can be heard. The
reserve fuel warning
lamp is lit and the fuel
gauge display shows 0. The fuel tank is empty.
X Refuel the vehicle. The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak or
discharged.
X Jump-start the vehicle (Y page 308).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to a thermal load that was too high.
X Allow the starter motor to cool down for approximately two
minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop, e.g. a Mercedes-Benz
Service Centre. Driving
149Driving and parking Z

on the ignition if you accidentally refuel
with the wrong fuel. Otherwise, the fuel will enter the fuel system. Even small amounts
of the wrong fuel could result in damage to the fuel system and the engine. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely.
! Overfilling the fuel tank could damage the
fuel system.
! Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
! Use a filter when adding fuel from a fuel
can. The fuel lines and/or the diesel injec-
tion system could otherwise be blocked by particles from the fuel can.
Do not get into the vehicle again during the
refuelling process. Otherwise, electrostatic
charge could build up again.
If you overfill the fuel tank, some fuel may
spray out when you remove the fuel pump
nozzle.
For further information on fuel and fuel quality (Y page 339). Refuelling
Opening/closing the fuel filler flap :
To open the fuel filler flap
; Tyre pressure table
= To insert the fuel filler cap
? Fuel type to be refuelled The fuel filler flap is unlocked or locked auto-
matically when you open or close the vehicle
with the key.
The position of the fuel filler cap is displayed
æ in the instrument cluster. The arrow
next to the filling pump indicates the side of
the vehicle.
Opening X
Switch off the engine.
X Remove the key from the ignition lock.
X Press the fuel filler flap in the direction of
arrow :.
The fuel filler flap swings up.
X Turn the fuel filler flap anti-clockwise and
remove it.
X Insert the fuel filler cap into holder on the
inside of fuel filler flap =.
X Completely insert the filler neck of the fuel
pump nozzle into the tank, hook in place
and refuel.
X Only fill the tank until the pump nozzle
switches off.
i Do not add any more fuel after the pump
stops filling for the first time. Otherwise,
fuel may leak out.
Closing X
Replace the cap on the filler neck and turn
clockwise until it engages audibly.
X Close the fuel filler flap.
i Close the fuel filler flap before locking the
vehicle. 160
RefuellingDriving and parking

Problems with the fuel and fuel tank
Problem
Possible causes/consequences and
M
MSolutions Fuel is leaking from the
vehicle. The fuel line or the fuel tank is faulty.
G WARNING
Risk of explosion or fire. X Turn the key to position 0in the ignition lock and remove it
immediately (Y page 143).
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The engine does not
start. The fuel tank of a vehicle with a diesel engine has been run com-
pletely dry.
X Refuel the vehicle with at least 5 litres of diesel.
X Turn the ignition on for approximately ten seconds
(Y page 143).
X Start the engine continuously for a maximum of ten seconds
until it runs smoothly.
or
X Start the engine using the touch-start function. To do this, turn
the key to position 3in the ignition lock and then release it
immediately (Y page 143).
If the engine does not start: X Turn the ignition on again a maximum of ten seconds
(Y page 143).
X Start the engine again continuously for a maximum of ten sec-
onds until it runs smoothly.
or
X Start the engine again via the touch-start function.
If the engine does not start after three attempts:
X Consult a qualified specialist workshop. Refuelling
161Driving and parking Z

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

cle from rolling away by applying the parking
brake.
Vehicles with manual transmission X
Shift to either first gear or reverse gear R.
X Turn the key to position 0in the ignition
lock and remove it.
The immobiliser is activated.
X Apply the electric parking brake.
Vehicles with automatic transmission All vehicles (except AMG vehicles)
X Apply the electric parking brake.
X Shift the transmission to position P.Selector lever in AMG vehicles
AMG vehicles:
X Apply the electric parking brake.
X Press Pbutton :.
X Turn the key to position 0in the ignition
lock and remove it.
The immobiliser is activated.
i If you switch the engine off with the trans-
mission in position Ror D, the automatic
transmission shifts to Nautomatically.
If you then open one of the front doors or
remove the key from the ignition, the auto-
matic transmission shifts to P.
If you shift the automatic transmission to N
before switching off the engine, the auto-
matic transmission remains in Neven if a
door is opened. Electric parking brake
General notes G
WARNING
If you leave children unattended in the vehi-
cle, they could set the vehicle in motion by, for example:
R releasing the parking brake
R shifting an automatic transmission out of
parking position P
R shifting a manual transmission into neutral
R starting the engine
They could also operate vehicle equipment.
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. i
The electric parking brake carries out a
function check at regular intervals when
the engine is switched off. Noises that
occur are normal.
Engaging/releasing manually Engaging
X Push handle :.
When the electric parking brake is applied,
the ! red indicator lamp lights up in the
instrument cluster.
i The electric parking brake can also be
applied when the key is removed. Parking
163Driving and parking Z

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 1or 2in
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 Dor 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 Por you have previously driven faster
than 3km/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 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
ParkingDriving an
d parking

Driving tips
General notes
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
more effort to steer and brake. There is a risk of an accident.
Do not switch off the ignition while driving. ECO display
The ECO display provides feedback on how
economical your driving characteristics are.
The ECO display assists you in achieving the
most economical driving style for the selec-
ted settings and prevailing conditions. Con-
sumption can be significantly influenced by
your driving style. Example: ECO display
The ECO display consists of three bars:
R Acceleration Acceleration
R Constant
Constant
R Coasting
Coasting
The percentage count is the mean value of the three bar values. The three bars and the mean
value begin at the value of 50%. A higher per- centage count indicates a more economical
driving style.
The ECO display does not indicate the actual
fuel consumption and a fixed percentage
count in the ECO display does not indicate a
fixed consumption figure. In addition to driving style, the consumption is
affected by many other factors, such as:
R load
R tyre pressure
R cold start
R choice of route
R the use of electrical consumers
These factors are not included in the ECO dis-
play.
The evaluation of your driving style takes the following three categories into consideration:
R Acceleration
Acceleration (evaluation of all accelera-
tion processes):
- The bar fills up: moderate acceleration,
especially at higher speeds
- The bar empties: sporty acceleration
R Constant Constant (assessment of driving behav-
iour at all times):
- The bar fills up: constant speed and
avoidance of unnecessary acceleration
and deceleration
- The bar empties: fluctuations in speed
R Coasting
Coasting (assessment of all deceleration
processes):
- The bar fills up: anticipatory driving,
keeping your distance and early release
of the accelerator. The vehicle can coast
without use of the brakes
- The bar empties: frequent braking
i An economical driving style involves driv-
ing at a moderate engine speed.
To achieve a higher value in the categories
Acceleration Acceleration andConstant
Constant:
R observe the gearshift recommendation.
R drive the vehicle in drive program E(vehi-
cles with automatic transmission).
i On long journeys at a constant speed, e.g.
on the motorway, only the bar for Constant
Constant
will change.
i The ECO display summarises the driving
characteristics from the start of the journey to its completion. Therefore, there are Driving tips
165Driving and pa rking Z

or a pneumatic drill, could cause PARK-
TRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It indicates visually and
audibly the distance between your vehicle
and an object.
PARKTRONIC is activated automatically if
you:
R switch on the ignition
R shift to position D,Ror Non vehicles with
automatic transmission
R release the electric parking brake
PARKTRONIC is deactivated at speeds above
18 km/h. It is reactivated at lower speeds.
PARKTRONIC monitors the area around your
vehicle using six sensors in the front bumper
and four sensors in the rear bumper.
Range of the sensors General notes
PARKTRONIC does not take into account
obstacles located:
R below the detection range, e.g. persons,
animals or objects
R above the detection range, e.g. overhang-
ing loads, tail sections or loading ramps of
goods vehicles :
Example: sensors in the front bumper,
left-hand side Side view
Top view
The sensors must be free of dirt, ice and
slush. Otherwise, they may not function cor-
rectly. Clean the sensors regularly, taking
care not to scratch or damage them
(Y page 294).
Front sensors Centre Approx. 100 cm
Corners Approx. 60 cm
Rear sensors
Centre Approx. 120 cm
Corners Approx. 80 cm
Minimum distance
Centre Approx. 20 cm
Corners Approx. 20 cm
If there is an obstacle within this range, the
relevant warning displays light up and a warn- ing tone sounds. If the distance falls below
the minimum, the distance may no longer be
shown. Driving systems
183Driving and parking Z

Deactivating/activating PARKTRONIC
:
Indicator lamp
; To deactivate/activate PARKTRONIC
If indicator lamp :lights up, PARKTRONIC is
deactivated.
i PARKTRONIC is automatically activated
when you turn the key to position 2in the
ignition lock.
Towing a trailer !
Fold in the ball coupling if the trailer tow
hitch is not required. PARKTRONIC meas-
ures the minimum detection range to an
obstacle from the bumper, not the ball cou-
pling.
PARKTRONIC is deactivated for the rear area when you establish an electrical connection
between your vehicle and a trailer. Driving syste
ms
185Driving an d parking Z