engine MERCEDES-BENZ A-CLASS HATCHBACK 2012 Owners Manual

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a positive terminal and an earth point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not inhale any battery gases. Do not lean over the battery. Keep children away from batteries. Wash battery acid immediately with water and seek
medical attention. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting. Do not lean over a battery. G
WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described order when connecting and disconnecting
the jump leads.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting. G
WARNING
Non-combusted fuel can collect in the exhaust system and ignite. There is a risk of fire. Avoid
repeated and lengthy starting attempts.
! Vehicles with a petrol engine:
avoid repeated and lengthy starting attempts. Otherwise,
the non-combusted fuel may damage the catalytic converter.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the
discharged battery has frozen. In this case you may neither jump-start the vehicle nor charge
the battery. The service life of a battery that has been thawed could be reduced. The starting 308
Jump-startingBreakdown assistance

characteristics may be impaired, especially at low temperatures. Have the thawed battery
checked at a qualified specialist workshop.
Do not use a rapid charging device to start the vehicle. If your vehicle's battery is discharged, the engine can be jump-started from another vehicle or from a second battery using jump
leads. Observe the following points:
R The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible,
jump-start the vehicle using a second battery or a jump-starting device.
R Vehicles with a petrol engine: only jump-start the vehicle when the engine and exhaust
system are cold.
R Do not start the engine if the battery is frozen. Let the battery thaw first.
R Jump-starting may only be performed from batteries with a nominal voltage of 12 V.
R Only use jump leads that have a sufficient cross-section and insulated terminal clamps.
R If the battery is fully discharged, leave the battery that is being used to jump-start connected
for a few minutes before attempting to start. This charges the empty battery a little.
R Make sure that the two vehicles do not touch.
Make sure that:
R the jump leads are not damaged.
R bare parts of the terminal clamp do not come into contact with other metal parts while the
jump leads are connected to the battery.
R the jump leads cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
X Secure the vehicle by applying the electric parking brake.
X Manual transmission: shift into neutral.
X Automatic transmission: shift the transmission to position P.
X Turn the key to position 0in the ignition lock and remove it.
X Switch off all electrical consumers (e.g. radio, blower, etc.).
X Open the bonnet (Y page 285). Jump-starting
309Breakdown assistance Z

Position number
Bidentifies the charged battery of the other vehicle or an equivalent jump-
starting device.
X Press together cover :of positive clamp ;and slide it back.
X Connect positive terminal ;on your vehicle to positive terminal =of donor battery B
using the jump lead, beginning with your own battery.
X Start the engine of the donor vehicle and run it at idling speed.
X Connect negative terminal ?of donor battery Bto earth point Aof your vehicle using the
jump lead, connecting the jump lead to donor battery Bfirst.
X Start the engine.
X Before disconnecting the jump leads, let the engines run for several minutes.
X First, remove the jump leads from earth point Aand negative terminal ?, then from pos-
itive clamp ;and positive terminal =. Begin each time at the contacts on your own vehicle
first.
X Close cover :of positive clamp ;after removing the jump leads.
X Have the battery checked at a qualified specialist workshop.
i Jump-starting is not considered to be a normal operating condition.
i Jump-starting cables and further information regarding jump starting can be obtained at
any qualified specialist workshop. Towing and tow-starting
Important safety notes
G
WARNING
Safety-relevant functions are restricted or not
available if:
R the engine is not running.
R the brake system or the power steering is
malfunctioning
R the voltage supply or the vehicle's electrical
system is malfunctioning.
If your vehicle is towed, significantly greater
force may be required to steer the vehicle or
to brake. There is a risk of an accident.
In such circumstances, use a towing bar.
Make sure that the steering is moving freely
before towing. G
WARNING
If the weight of the vehicle to be towed or tow- started is greater than the permissible gross
weight of your vehicle:
R the towing eye could detach itself
R the vehicle/trailer combination could over-
turn.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per-
missible gross weight of your vehicle.
Information on your vehicle's gross vehicle
weight rating can be found on the vehicle
identification plate (Y page 338). G
WARNING
The vehicle is braked when the HOLD function or DISTRONIC PLUS is activated. Therefore,
deactivate HOLD and DISTRONIC PLUS if the
vehicle is to be towed. 310
Towing and tow-startingBreakdown assistance

Vehicles with a TIREFIT kit: the towing eye
is located under the tyre inflation compres-
sor.
X Press the mark on cover :inwards in the
direction of the arrow.
X Remove cover :from the opening.
X Screw the towing eye in clockwise to the
stop and tighten it.
Vehicles with a trailer tow hitch do not have a bracket for the screw-in towing eye at the
back. If you intend to use the vehicle for tow- ing, fold out the ball coupling (Y page 203)
and secure the towbar to it.
Removing the towing eye X
Loosen the towing eye and unscrew it.
X Attach cover :to the bumper and press
until it engages.
X Place the towing eye in the stowage well
under the luggage compartment floor
(Y page 299).
X Vehicles with a TIREFIT kit: replace the tyre
inflation compressor. Towing the vehicle with the front axle
raised
Only vehicles without 4MATIC can be
towed with the front axle raised.
! Vehicles with 4MATIC must not be towed
with the front or rear axle raised; otherwise, the transmission may be damaged.
Vehicles with 4MATIC may either be towed
away with both axles on the ground or be loa-
ded up and transported.
! The ignition must be switched off if you
are towing the vehicle with the front axle
raised. Intervention by ESP ®
could other-
wise damage the brake system.
X Turn the key to position 2in the ignition
lock.
X When the vehicle is stationary, depress the
brake pedal and keep it depressed. X
Vehicles with manual transmission:
depress the clutch pedal fully and shift to
neutral.
or
X Vehicles with automatic transmission:
shift the automatic transmission to posi-
tion P.
X Release the brake pedal.
X Release the electric parking brake.
X Deactivate automatic locking (Y page 223).
X Switch on the hazard warning lamps
(Y page 108).
X Turn the key in the ignition lock to position
0 and leave the key in the ignition lock.
When towing your vehicle with the front axle
raised, it is important that you observe the
safety instructions (Y page 310). Towing the vehicle with both axles on
the ground G
WARNING
The power assistance for the steering and the brake force booster do not work when the
engine is not running. You will then need
much more effort to brake and steer the vehi-
cle. Adapt your style of driving accordingly.
i In order to signal a change of direction
when towing with the hazard warning lamps switched on, use the combination switch asusual. In this case, only the turn signals for
the desired direction flash. When you reset
the combination switch, the hazard warn-
ing lamps start flashing again. 312
Towing and tow-startingBreakdown assistance

Tow-starting (emergency engine
starting)
! Do not tow-start vehicles with automatic
transmission. You could otherwise damage the automatic transmission.
Before tow-starting, the following conditions
must be fulfilled:
R the battery is connected.
R the engine has cooled down.
R the exhaust system has cooled down.
X Switch on the hazard warning lamps
(Y page 108).
X Fit the towing eye (Y page 311).
X Secure the rigid towing bar or the towing
rope.
X Depress and hold the brake pedal.
X Turn the key to position 2in the ignition
lock.
X Depress the clutch pedal and keep it
depressed.
X Engage neutral.
X Release the brake pedal.
X Tow-start the vehicle.
X Engage second gear.
X Release the clutch pedal slowly without
depressing the accelerator pedal.
The engine is started.
X Depress the clutch pedal and shift to neu-
tral.
X Stop at a suitable place.
X Secure the vehicle by applying the electric
parking brake.
X Remove the rigid towing bar or towing rope.
X Remove the towing eye (Y page 312).
X Switch off the hazard warning lamps.
When tow-starting, it is important that you
observe the safety instructions (Y page 310)
and the legal requirements for the relevant
countries. Electrical fuses
Important safety notes
G
WARNING
If you manipulate, bridge or replace a faulty
fuse with a fuse of a higher amperage, the
electric cables could be overloaded. This may result in a fire. There is a risk of an accident
and injury.
Always replace faulty fuses with specified new fuses of the correct amperage.
! Only use fuses that have been approved
for Mercedes-Benz vehicles and which
have the correct fuse rating for the system concerned. Only use fuses marked with an
"S". Components or systems could other-
wise be damaged.
The fuses in your vehicle serve to disconnect faulty circuits. If a fuse blows, all the compo-
nents on the circuit and their functions will
fail.
Blown fuses must be replaced with fuses of
the same rating, which you can recognise by
the colour and fuse rating. The fuse ratings
are listed in the fuse allocation chart.
If the newly inserted fuse also blows, have the cause traced and rectified at a qualified spe-
cialist workshop, e.g. a Mercedes-Benz Ser-
vice Centre. Before replacing a fuse
X Secure the vehicle against rolling away
(Y page 162).
X Switch off all electrical consumers.
X Turn the key to position 0in the ignition
lock and remove it (Y page 143). All indi-
cator lamps in the instrument cluster must be off.
The fuses are located in various fuse boxes:
R fuse box in the engine compartment on the
left-hand side of the vehicle, when viewed
in the direction of travel
R fuse box in the front-passenger footwell 314
Electrical fusesBreakdown assistance

The fuse allocation chart is on the fuse box in
the front-passenger footwell (Y page 315).Fuse box in the engine compartment
G
WARNING
When the bonnet is open, and the windscreen wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windscreen wipers and
the ignition before opening the bonnet.
! Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture
seeping in or dirt could otherwise impair
the operation of the fuses. X
Open the bonnet.
X Remove any existing moisture from the
fuse box using a dry cloth.
X To open: open clamps ;.
X Fold cover :up in the direction of the
arrow and remove it. X
To close: check whether the seal is lying
correctly in cover :.
X Insert cover :at the back into openings
= on the fuse box.
X Fold down cover :.
X Hook clamps ;into the fuse box and
close.
X Close the bonnet. Fuse box in the front-passenger foot-
well
X
To open: remove the floormat from the
front-passenger side.
X Fold out perforated floor covering :in the
direction of the arrow. Electrical fuses
315Breakdown assistance Z

Do not use high-pressure cleaners with circu-
lar-jet nozzles to clean the vehicle. Have dam-aged tyres or chassis components replaced
immediately. Fitting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the electric parking brake manually
(Y page 163).
X Bring the front wheels into the straight-
ahead position.
X Vehicles with manual transmission:
engage first or reverse gear.
X Vehicles with automatic transmission:
move the DIRECT SELECT lever to P.
X Switch off the engine.
X Remove the key from the ignition lock.
X If a trailer is coupled to the vehicle, uncou-
ple it.
X If included in the vehicle equipment,
remove the tyre-change tool kit from the
vehicle.
X Secure the vehicle to prevent it from rolling
away.
i Apart from certain country-specific varia-
tions, vehicles are not equipped with a tyre-
change tool kit. For information on which
tools are required to perform a wheel
change on your vehicle, consult a
Mercedes-Benz Service Centre.
Necessary wheel-changing tools can
include, for example:
R Jack
R Wheel chock
R Wheel wrench Securing the vehicle against rolling
away
If your vehicle is equipped with a wheel chock,
it can be found in the tyre-change tool kit
(Y page 299).
The folding wheel chock is an additional
securing measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
X Fold both plates upwards :.
X Fold out lower plate ;.
X Guide the lugs on the lower plate fully into
the openings in base plate =. Securing the vehicle on level ground
X On level ground: place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change. Changing a
wheel
325Wheels an d tyres Z

Securing the vehicle on slight downhill gradients
X On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
Observe the following when raising the
vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If the jack is
used incorrectly, it could tip over while the
vehicle is raised.
R the jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suitable for per-
forming maintenance work under the vehi- cle.
R avoid changing the wheel on uphill and
downhill slopes.
R before raising the vehicle, secure it from
rolling away by applying the parking brake
and positioning wheel chocks. Never release the parking brake while the vehicle
is raised.
R the jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, load-bearing underlay must be used.
On a slippery surface, a non-slip underlay
must be used, e.g. rubber mats.
R do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R make sure that the distance between the
underside of the tyres and the ground does
not exceed 3 cm.
R never place your hands or feet under the
raised vehicle.
R never lie under the raised vehicle.
R never start the engine when the vehicle is
raised.
R never open or close a door or the tailgate
when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised. Steel wheel with wheel trim
X Vehicles with steel wheels: carefully
reach into two of the wheel trim openings
and remove the wheel trim.
Vehicles with hub caps: the hub cap covers
the wheel bolts. Before you can unscrew the
wheel bolts, you must remove the hub cap. 326
Changing a wheelWheels and tyres

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). Information on technical data
You can find technical data on the Internet at: http://www.mercedes-benz.com
i The technical data was determined in
accordance with EC Directives. All data
applies to the vehicle's standard equip-
ment. It may therefore differ for vehicles
with optional equipment. You can obtain
further information from a Mercedes-Benz
Service Centre. Vehicle electronics
Tampering with the engine electron-
ics
! Only have work carried out on the engine
electronics and its associated parts, such
as control units, sensors and connector
leads, at a qualified specialist workshop.
Vehicle components may otherwise wear
more quickly and the vehicle's operating
permit may be invalidated. Retrofitting two-way radios and
mobile phones (RF transmitters)
G
WARNING
If RF transmitters are tampered with or not
properly retrofitted, the electromagnetic radi- ation they emit can interfere with the vehicle
electronics. This may jeopardise the opera-
tional safety of the vehicle. There is a risk of an accident.
You should have all work on electrical and
electronic components carried out at a quali-
fied specialist workshop. G
WARNING
If you use the RF transmitter in the vehicle in
an improper way, its electromagnetic radia-
tion can disrupt vehicle electronics, e.g. if:
R the RF transmitter is not connected to an
exterior aerial
R the exterior aerial is fitted incorrectly or is
not a low-reflection aerial
This can jeopardise the operating safety of the vehicle. There is a risk of an accident.
Have the low-reflection exterior aerial fitted at
a qualified specialist workshop. When oper-
ating in the vehicle, always connect the RF
transmitter to the low-reflection exterior aer-
ial.
! The operating permit may be invalidated if
the instructions for installation and use of
RF transmitters are not observed.
In particular, the following conditions must be complied with:
R only approved wavebands may be used.
R observe the maximum permissible out-
put in these wavebands.
R only approved aerial positions may be
used.
Observe the notes on operating mobile
phones (Y page 279).
The following aerial positions may be used for
the correct installation of RF transmitters: 336
Vehicle electronicsTechnical data

Identification plates
Vehicle identification plate with vehi-
cle identification number (VIN) X
Open the front right-hand door.
You will see vehicle identification plate :.Example: vehicle identification plate
:
Vehicle identification plate
; Vehicle manufacturer (Daimler AG)
= EU type approval number (only for certain
countries)
? VIN
A Maximum permissible gross vehicle
weight (kg)
B Maximum permissible mass of vehicle/
trailer combination (kg)
C Maximum permissible front axle load (kg)
D Maximum permissible rear axle load (kg)
E Paint code
i The data shown on the vehicle identifica-
tion plate is example data. This data is dif-
ferent for every vehicle and can deviate
from the data shown here. You can find the data applicable to your vehicle on the vehi-
cle's identification plate. VIN
X
Slide the right-hand front seat to its rear-
most position.
X Fold up floor covering :in front of the
right-hand front seat.
You will see VIN ;.
The VIN can also be found on the vehicle
identification plate (Y page 338). Engine number
The engine number is stamped onto the
crankcase. More information can be obtained
from any Mercedes-Benz Service Centre. Service products and capacities
Important safety notes
G
WARNING
Service product can be poisonous and haz-
ardous to health. There is a risk of injury.
Observe the instructions on the respective
original container when using, storing and dis- posing off service products. Always store ser-
vice products in the sealed original container. Always keep service products out of the reach
of children. 338
Service products and capacitiesTechnical data