check engine MERCEDES-BENZ A-CLASS HATCHBACK 2015 Service Manual

X
Pull support strut ?out of bracket A.
X Lift up support strut ?and insert it into
yellow retaining clip =.
Closing the bonnet X
Raise the bonnet slightly and, at the same
time, remove support strut ?from yellow
retaining clip =.
X Swing support strut ?down and press it
into bracket Auntil it engages.
X Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Do not press the bonnet
closed. Open the bonnet again and close it with a little more force. Engine oil
General notes Depending on your driving style, the vehicle
consumes up to 0.8 litres of oil per 1,000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently
drive at high engine speeds.
Depending on the engine, the oil dipstick may be installed at a different location. When checking the oil level:
R park the vehicle on a level surface
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
R if the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly, wait approximately
30 minutes before carrying out the meas-
urement
Checking the oil level using the oil dip-
stick G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. 324
Engine compartmentMaintenance and care

Damage to the engine or exhaust system is
caused by the following:
R using engine oils and oil filters that have
not been specifically approved for the
service system
R changing the engine oil and oil filter after
missing the change interval required by
the service system
R using engine oil additives
! Do not add too much oil. Topping up with
too much engine oil can result in damage to
the engine or to the catalytic converter.
Have excess engine oil siphoned off. Example: engine oil filler cap
X Turn cap :anti-clockwise and remove it.
X Top up the engine oil.
If the oil level is at or below the MIN mark on
the oil dipstick, top up with 1.0 lof engine
oil.
X Replace cap :on the filler neck and turn
clockwise.
Make sure that the cap locks securely into place.
X Check the oil level again with the oil dip-
stick (Y page 324).
For further information on engine oil, see
(Y page 400). Checking and adding other service
products
Checking the coolant level G
WARNING
The cooling system is pressurised, particu-
larly when the engine is warm. If you open the cap, you could be scalded if hot coolant
sprays out. There is a risk of injury.
Let the engine cool down before you open the
cap. Wear gloves and eye protection. Open
the cap slowly to release the pressure.
! The coolant level must only be checked
and corrected when the engine has cooled
down (coolant temperature under 40 †).
Checking the coolant level when the cool-
ant temperature is over 40 † can lead to
damage to the engine or engine cooling
system. Example
X Park the vehicle on a level surface.
Only check the coolant level if the vehicle is
on a level surface and the engine has
cooled down.
X Turn the key to position 2in the ignition
lock (Y page 157).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
40 †.
X Turn the key to position 0in the ignition
lock (Y page 157). 326
Engine compartmentMaintenance and care

Depending on the operating conditions of the
vehicle, the remaining time or distance until
the next service due date is displayed.
The letter indicates which service is due. A A
stands for a minor service and B
Bfor a major
service. A number or another letter may be
displayed after the letter.
Only for certain countries: the position after
the letter A
A or B Bindicates any necessary addi-
tional maintenance work. If you notify a quali- fied specialist workshop of this display, you
will receive a statement on the associated
costs.
The ASSYST PLUS service interval display
does not take into account any periods of
time during which the battery is disconnec-
ted.
Maintaining the time-dependent service
schedule:
X Note down the service due date displayed
in the multifunction display before discon-
necting the battery.
or
X After reconnecting the battery, subtract
the battery disconnection periods from the service date shown on the display. Hiding service messages
X Press the aor% button on the steer-
ing wheel. Displaying service messages
X Switch the ignition on.
X Press the =or; button to select the
Serv. Serv. menu.
X Press the 9or: button to select the
ASSYST PLUS
ASSYST PLUS submenu and confirm by
pressing the abutton.
The service due date appears in the multi-
function display. Information about Service
Resetting the ASSYST PLUS service
interval display !
If the ASSYST PLUS service interval dis-
play has been inadvertently reset, this set-
ting can be corrected at a qualified special-
ist workshop.
Have service work carried out as described in the Service Booklet. This may otherwise
lead to increased wear and damage to the
major assemblies or the vehicle.
A qualified specialist workshop, e.g. a
Mercedes-Benz Service Centre, will reset the ASSYST PLUS service interval display after
the service work has been carried out. You
can also obtain further information on main-
tenance work, for example.
Special service requirements The prescribed service interval is based on
normal operation of the vehicle. Service work
will need to be performed more often if the
vehicle is operated under arduous conditions
or increased loads, for example:
R regular city driving with frequent intermedi-
ate stops
R if the vehicle is primarily used to travel
short distances
R for frequent operation in mountainous ter-
rain or on poor road surfaces
R if the engine is often left idling for long peri-
ods
In these or similar operating conditions, have,
for example, the air filter, engine oil and oil
filter changed more frequently. The tyres
must be checked more frequently if the vehi-
cle is operated under increased loads. Fur-
ther information can be obtained at a quali-
fied specialist workshop, e.g. a Mercedes-
Benz Service Centre. 328
ASSYST PLUSMaintenance and care

Flat tyre
Preparing the vehicle
Your vehicle may be equipped with: R MOExtended tyres (tyres with run-flat char-
acteristics) (Y page 340)
Vehicle preparation is not necessary on
vehicles with MOExtended tyres.
R a TIREFIT kit (Y page 339)
R an emergency spare wheel (certain coun-
tries only) (Y page 389)
Vehicles with MOExtended tyres are not
equipped with a TIREFIT kit at the factory. It is therefore recommended that you additionallyequip your vehicle with a TIREFIT kit if you fit tyres that do not feature run-flat characteris-
tics, e.g. winter tyres. A TIREFIT kit can be
obtained from a qualified specialist work-
shop.
Information on changing and fitting a wheel
(Y page 367).
X Stop the vehicle as far away as possible
from traffic on solid, non-slippery and level
ground.
X Switch on the hazard warning lamps.
X Secure the vehicle against rolling away
(Y page 184).
X If possible, bring the front wheels into the
straight-ahead position.
X Switch off the engine.
X Vehicles without KEYLESS-GO: remove
the key from the ignition lock.
X Vehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: open the driver's
door.
The on-board electronics now have status
0 . This is the same as the key having been
removed.
X Vehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: remove the Start/
Stop button from the ignition lock
(Y page 157).
X Make sure that the passengers are not
endangered as they do so. Make sure that no one is near the danger area while a
wheel is being changed. Anyone who is not
directly assisting in the wheel change
should, for example, stand behind the bar-
rier.
X Get out of the vehicle. Pay attention to traf-
fic conditions when doing so.
X Close the driver's door.
X Place the warning triangle at a suitable dis-
tance (Y page 338). Observe legal require-
ments. MOExtended tyres (tyres with run-flat
characteristics)
General notes With MOExtended tyres (tyres with run-flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tyres. The affected
tyre must not show any clearly visible dam-
age.
You can recognise MOExtended tyres by the
MOExtended marking which appears on the
tyre wall. You will find this marking next to the
tyre size designation, the load-bearing capa-
city and the speed index.
MOExtended tyres may only be used in con-
junction with an activated tyre pressure loss
warning system or tyre pressure monitor.
If a pressure loss warning message
appears in the multifunction display:
R observe the instructions in the display mes-
sages (Y page 283)
R check the tyre for damage
R if driving on, observe the following notes
The driving distance possible in run-flat mode is approximately 80 km when the vehicle is
partially laden and approximately 30 km
when the vehicle is fully laden. 340
Flat tyreBreakdown assistance

lection point for used batter-
ies.
! Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Service
Booklet or contact a qualified specialist
workshop for more information.
! You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery yourself, make sure that:
R you switch off the engine and remove the
key. On vehicles with KEYLESS-GO,
ensure that the ignition is switched off.
Check that all the indicator lamps in the
instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
R in vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be fitted securely dur- ing operation.
Comply with safety precautions and take pro-
tective measures when handling batteries. Risk of explosion
Fire, naked flames and smoking
are prohibited when handling the
battery. Avoid creating sparks.
Battery acid is caustic. Avoid con-
tact with the skin, eyes or clothing. Wear suitable protective clothing,
in particular gloves, an apron and a
face mask.
Immediately rinse acid splashes
off with clean water. Consult a doc-
tor if necessary. Wear eye protection.
Keep children away.
Observe this Owner's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehi-
cle occupants from suffering acid burns
should the battery be damaged in the event of
an accident.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the
vehicle. In such cases, have the battery dis-
connected at a qualified specialist workshop. You can also charge the battery with a
charger recommended by Mercedes-Benz.
For more information, please contact a quali-
fied specialist workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked up for a long period of time.
When you park the vehicle, remove the key if you do not require any electrical consumers.
The vehicle will then use very little energy,
thus conserving battery power. 346
Battery (vehicle)Breakdown assistance

If the power supply has been interrupted, e.g.
if the battery was discharged, you will have to:
R set the clock via Audio 20 or COMAND
Online (see separate operating instruc-
tions)
R reset the function for folding the exterior
mirrors in/out automatically, by folding the mirrors out once (Y page 114). Charging the battery
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
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not breathe in any battery gases. Do not
lean over the battery. Keep the batteries out
of the reach of children. Immediately rinse off
battery acid thoroughly with plenty of clean
water and seek medical attention at once. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing 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.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
! Only
charge the battery using the jump-
start connection point.
The jump-starting connection point is in the
engine compartment (Y page 348).X
Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order
as when connecting the donor battery in
the jump-starting procedure (Y page 348).
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 bat-
tery that has been thawed may be reduced.
The starting characteristics may be impaired,
especially at low temperatures. Have the
thawed battery checked at a qualified spe-
cialist workshop.
Only charge the installed battery with a bat-
tery charger which has been tested and
approved by Mercedes-Benz. A battery
charger unit specially adapted for Mercedes-
Benz vehicles and tested and approved by
Mercedes-Benz is available as an accessory.
This device permits charging of the battery in position. Contact a Mercedes-Benz Service
Centre for information and availability. Read
the battery charger's operating instructions
before charging the battery. Battery (vehicle)
347Breakdown assistance Z

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 breathe in any battery gases. Do not lean over the battery. Keep the batteries out of the reach of children. Immediately rinse off battery acid
thoroughly with plenty of clean water and seek medical attention at once. 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.
! 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. Let the battery thaw first. The service life of a battery that has been thawed may
be reduced. The starting characteristics may be impaired, especially at low temperatures.
Have the thawed battery checked at a qualified specialist workshop. 348
Jump-startingBreakdown assistance

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 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.
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 Close the bonnet.
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 away and tow-starting
Important safety notes
G
WARNING
Safety relevant functions are restricted or no
longer available if:
R the engine is not running
R the brake system or power steering is mal-
functioning
R there is a malfunction in the voltage supply
or the vehicle's electrical system
When your vehicle is towed away or towed
started, you may require considerably more
effort to steer and brake. There is a risk of an
accident.
In such cases use a rigid towing bar. Before
being towed away or tow started, make sure
the steering moves freely. G
WARNING
If the steering wheel lock is engaged, the vehi- cle can no longer be steered. There is a risk of
an accident.
Always switch on the ignition when towing
with a tow rope or a towing bar. G
WARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible gross weight of your vehicle, the:
R towing eye may be torn off
R car/trailer combination may swerve or
even overturn
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.
Details on the permissible gross vehicle
weight of your vehicle can be found on the
vehicle identification plate (Y page 396).
! When COLLISION PREVENTION ASSIST
PLUS, DISTRONIC PLUS or the HOLD func- tion is activated, the vehicle brakes auto-
matically in certain situations. To avoid
damage to the vehicle, deactivate these
systems in the following or similar situa-
tions:
R when towing away
R in a car wash 350
Towing away and tow-startingBreakdown assistance

Interchanging the front and rear wheels of
differing dimensions can render the general
operating permit invalid.
Observe the instructions and safety notes in
the "Changing a wheel" section (Y page 367).
The wear patterns on the front and rear tyres differ depending on the operating conditions.
Interchange the wheels before a clear wear
pattern has formed on the tyres. Front tyres
typically wear more on the shoulders and the
rear tyres in the centre.
On vehicles that have the same size front and rear wheels, you can interchange the wheels
every 5,000 to 10,000 km depending on the
degree of tyre wear. Ensure the direction of
rotation is maintained.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is interchanged. Check the tyre pressure and, if necessary, restart the tyre pressure loss
warning system or the tyre pressure monitor. Direction of rotation
Tyres with a specified direction of rotation
have additional benefits, e.g. if there is a risk
of aquaplaning. These advantages can only be gained if the tyres are fitted corresponding to the direction of rotation.
An arrow on the sidewall of the tyre indicates
its correct direction of rotation. Storing wheels
Store wheels in a cool, dry and preferably
dark place if they are not being used. Protect
the tyres against oil, grease, petrol and diesel. Fitting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the electric parking brake manually. X
Move the front wheels to the straight-
ahead position.
X Vehicles with manual transmission:
depress the clutch pedal fully and engage
first or reverse gear.
X Vehicles with automatic transmission:
shift the automatic transmission to posi-
tion P.
X Switch off the engine.
X Vehicles without KEYLESS-GO: remove
the key from the ignition lock.
X Vehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: open the driver's
door.
The on-board electronics now have status
0. This is the same as the key having been removed.
X Vehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: remove the Start/
Stop button from the ignition lock
(Y page 157).
X If included in the vehicle equipment,
remove the tyre-change tool kit from the
vehicle.
X Safeguard the vehicle against rolling away
(Y page 184).
i Apart from some country-specific var-
iants, vehicles are not equipped with tyre-
changing tools. Some tools for changing a
wheel are specific to the vehicle. For more information on which tools are required to
perform a wheel change on your vehicle,
consult a qualified specialist workshop.
Necessary tyre-changing tools may
include, for example:
R Jack
R Wheel chock
R Wheel wrench 368
Changing a wheelWheels and tyres

Comply with the important safety precautions
for service products when handling coolant
(Y page 396).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It is responsible
for the following:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
If antifreeze/corrosion inhibitor is present in
the correct concentration, the boiling point of
the coolant during operation will be approx-
imately 130 †.
The antifreeze/corrosion inhibitor concentra- tion in the engine cooling system should:
R be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -37 †.
R not exceed 55% (antifreeze protection
down to -45 †). Heat will otherwise not be
dissipated as effectively.
Mercedes-Benz recommends coolant or anti- freeze/corrosion inhibitor concentrate in
accordance with
MB Specifications for Service Products 310.1 .
i When the vehicle is first delivered, it is fil-
led with a coolant mixture that ensures
adequate antifreeze and corrosion protec-
tion.
i The coolant is checked at every mainte-
nance interval at a qualified specialist
workshop. Windscreen washer system
Important safety notes G
WARNING
If windscreen washer concentrate comes into contact with hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury. Make sure the windscreen washer concen-
trate does not come into contact with the filler
neck.
! Only use washer fluid that is suitable for
plastic lamp lenses, e.g. MB SummerFit or
MB WinterFit. Unsuitable washer fluid
could damage the plastic lenses of the
headlamps.
! Do not use distilled or de-ionised water in
the washer fluid reservoir. Otherwise, the
level sensor may be damaged.
! Only the washer fluids SummerFit and
WinterFit can be mixed. Otherwise, the
spraying nozzles could become blocked.
Comply with the important safety notes for
service products when handling washer fluid
(Y page 396).
At temperatures above freezing:
X Fill the washer fluid reservoir with a mixture
of water and washer fluid, e.g. MB Sum-
merFit.
Mix 1 part MB SummerFit to 100 parts water.
At temperatures below freezing:
X Fill the washer fluid reservoir with a mixture
of water and washer fluid, e.g. MB Winter-
Fit.
For the correct mixing ratio refer to the
information on the antifreeze reservoir.
i Add washer fluid concentrate, e.g. MB
SummerFit or MB WinterFit, to the washer
fluid all year round. Service products and capacities
403Technical data Z