check engine MERCEDES-BENZ A-CLASS HATCHBACK 2015 User Guide

Problem
Possible causes/consequences and
M
MSolutions There is a fault with KEYLESS-GO.
X Lock/unlock the vehicle using the remote control function of
the key.
X Have the vehicle and key checked at a qualified specialist work-
shop.
If the vehicle can also not be locked/unlocked using the remote
control function:
X Lock (Y page 91) or unlock (Y page 92) the vehicle using the
emergency key element.
X Have the vehicle and key checked at a qualified specialist work-
shop. The engine cannot be
started using the key. the on-board voltage is too low
X Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work: X Check the starter battery and charge it if necessary
(Y page 347).
or
X Jump-start the vehicle (Y page 348).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The key is
in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The key battery is discharged or nearly discharged.
X Check the key battery (Y page 86) and replace it if necessary
(Y page 86).
If this does not work: X Start your vehicle with the key in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the key in the ignition lock. 88
KeyOpening and closing

On right-hand-drive vehicles, turn the
emergency key element clockwise.
The door is unlocked.
X Turn the emergency key element back and
remove it.
X Insert the emergency key element into the
key (Y page 85). Locking the vehicle (emergency key
element)
If the vehicle can no longer be locked with the key or KEYLESS-GO, use the emergency key
element.
X Open the driver's door.
X Close the front-passenger door, the rear
doors and the tailgate.
X Press the locking button on the driver’s
door (Y page 90).
X Check whether the locking knobs on the
front-passenger door and the rear doors
are still visible. Press the locking knobs
down by hand if necessary.
X Close the driver's door.
X Take the emergency key element out of the
key (Y page 85).
X Insert the emergency key element into the
lock of the driver's door as far as it will go. X
Turn the emergency key element clockwise
as far as it will go to position 1.On right-hand-drive vehicles, turn the
emergency key element anti-clockwise.
X Turn the emergency key element back and
remove it.
X Make sure that the doors and the tailgate
are locked.
X Insert the emergency key element into the
key (Y page 85).
i If you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not primed. Luggage compartment
Important safety notes
G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. If the tailgate is open when the engine is running, particu-
larly if the vehicle is moving, exhaust fumes
could enter the passenger compartment.
There is a risk of poisoning.
Turn off the engine before opening the tail-
gate. Never drive with the tailgate open. G
WARNING
If objects, luggage or loads are not secured or not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, especially when braking or abruptly changing directions.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
! The tailgate swings upwards and to the
rear when opened. Therefore, make sure
that there is sufficient clearance above and behind the tailgate.
The opening dimensions of the tailgate can be
found in the "Vehicle data" section
(Y page 404). 92
Luggage compartmentOpening and closing

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). Correct driver's seat position
G
WARNING
You could lose control of the vehicle while
driving if you:
R adjust the driver's seat, steering wheel or
mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirrors and fasten your seat
belt before starting the engine. X
Observe the safety notes on seat adjust-
ment (Y page 107).
X Make sure that seat =is correctly adjus-
ted.
Manual seat adjustment (Y page 108)
Electrical seat adjustment (Y page 109)
When adjusting the seat, make sure that:
R you are as far away from the driver's air-
bag as possible
R you are sitting in a normal upright posi-
tion
R you can fasten the seat belt properly
R you have moved the backrest to an
almost vertical position
R you have set the seat angle so that your
thighs are gently supported
R you can depress the pedals properly
X Check whether the head restraint is adjus-
ted correctly (Y page 109).
When doing so, make sure that you have
adjusted the head restraint so that the back of your head is supported at eye level by the
centre of the head restraint.
X Observe the safety notes on steering col-
umn adjustment (Y page 112).
X Make sure that steering wheel :is adjus-
ted correctly.
Adjusts the steering wheel (Y page 112)
When adjusting the steering wheel, make
sure that:
R you can hold the steering wheel with your
arms slightly bent
R you can move your legs freely
R you can see all the displays in the instru-
ment cluster clearly
X Observe the safety guidelines for seat belts
(Y page 42).
X Check whether you have fastened seat
belt ;properly (Y page 44).106
Correct driver's seat positionSeats, steering wheel and mirrors

Problems with the seat heating
Problem
Possible causes/consequences and
M
MSolutions The seat heating has
switched off prema-
turely or cannot be
switched on. The on-board voltage is too low because too many electrical con-
sumers are switched on.
X Switch off electrical consumers that you do not need, such as
the rear window heating or interior lighting.
Once the battery is sufficiently charged, the seat heating will
switch back on automatically. Steering wheel
Important safety notes
G
WARNING
You could lose control of the vehicle while
driving if you:
R adjust the driver's seat, steering wheel or
mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirrors and fasten your seat
belt before starting the engine. G
WARNING
Children could become trapped by the steer-
ing wheel if they adjust it. There is a risk of
injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children unattended in the vehicle. Adjusting the steering wheel
G
WARNING
The steering wheel may move unexpectedly if you adjust it while driving. This could cause
you to lose control of the vehicle. There is a
risk of an accident.
Make sure that the steering wheel is locked
before driving off. Never unlock the steering
wheel when the vehicle is in motion. :
Release lever
; Adjusts the steering wheel height
= Adjusts the steering wheel position (fore-
and-aft adjustment)
X Push release lever :down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired
position.
X Push release lever :up as far as it will go.
The steering column is locked.
X Check if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction. 112
Steering wheelSeats, steering wheel and mirrors

and observe the important safety notes when
doing so (Y page 151).
Switching the auxiliary heating/ventila-
tion on/off Remote control
:
Display
; u Switches on the auxiliary heating/
ventilation/checks status
= . Sets the departure time
? ^ Switches off the auxiliary heating/
ventilation
A , Sets the departure time
X To switch on: press and hold the u
button.
ON is shown in the remote control display.
X To switch off: press and hold the ^
button.
OFF is shown in the remote control display.
Checking the status of the auxiliary heat-
ing/ventilation
X Briefly press the ubutton.
The following messages may appear in the
display: Display Meaning
The auxiliary heating/
ventilation is switched
off. The auxiliary ventilation
is switched on. The num-
ber in the display shows
the remaining time (in
minutes) for the auxiliary
ventilation. The auxiliary heating is
switched on. The number
in the display shows the
remaining time (in
minutes) for the auxiliary heating. A departure time has
been activated. The
departure time appears
in the display.
A departure time has
been activated. The aux-
iliary ventilation is cur-
rently activated. The
number in the display
shows the remaining
time (in minutes) for the
auxiliary ventilation. If
the vehicle is not started
after this time, the run-
ning time is increased by
five minutes. A departure time has
been activated. The aux-
iliary heating is currently
activated. The number in
the display shows the
remaining time (in
minutes) for the auxiliary heating. If the vehicle is
not started after this
time, the running time is
increased by five
minutes. If the engine has not yet reached operating
temperature when it is started, the auxiliary
heating running time is increased. The auxili-
ary heating continues to run until the operat- 150
Operating the climate control systemClimate control

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
more effort to steer and brake. There is a risk of an accident.
Do not switch off the ignition while driving. G
WARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine when the vehi-
cle is stationary. Drive off immediately.
Avoid high engine speeds and driving at full throttle until the engine has reached its
operating temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train.
! Mercedes-AMG vehicles:
avoid full-load
operation and engine speeds greater than
5000 rpm when the engine is cold. This will
help to protect the engine and maintain
smooth engine operation. Key positions
Key g
To remove the key
1 Power supply for some consumers, such
as the windscreen wipers
2 Ignition (power supply for all consumers)
and drive position
3 To start the vehicle
Vehicles with manual transmission: the
steering is locked when the key is taken out of
the ignition lock.
i If the key does not belong to the vehicle, it
can still be turned in the ignition lock. How-
ever, the ignition will not be switched on.
The engine cannot be started.
Start/Stop button General notes
Vehicles with KEYLESS-GO are equipped with
keys featuring an integrated KEYLESS-GO
function and a detachable Start/Stop button.
A check which periodically establishes a radio
connection between the vehicle and the key
determines whether a valid key is in the vehi- cle. This occurs, for example, when starting
the engine.
When you insert the Start/Stop button into
the ignition lock, the system needs approx-
imately two seconds recognition time. You
can then use the Start/Stop button. Driving
157Driving and parking Z

Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the key.
You can only switch between Start/Stop but-
ton mode and key operation when the vehicle is stationary.
You must also engage park position P(vehi-
cles with automatic transmission).
X Remove Start/Stop button :from ignition
lock ;.
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take the key with you when leaving the vehicle. As long as the key is in the vehicle:
R the vehicle can be started using the Start/
Stop button
R the electrically powered equipment can be
operated Starting the vehicle
Important safety notes G
WARNING
If children are left unsupervised in the vehicle, they could:
R open doors, thereby endangering other per-
sons or road users
R get out and be struck by oncoming traffic
R operate vehicle equipment and become
trapped, for example
In addition, the children could also set the
vehicle in motion, for example, if 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
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 and animals unattended in the vehi-
cle. Keep the keys out of the reach of children.
G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation. G
WARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
! Do not depress the accelerator when
starting the engine.
General notes Vehicles with a petrol engine:
the engine
runs at a higher engine speed during the cold
start procedure so that the catalytic con-
verter can reach operating temperature more quickly. The sound of the engine may change
as a result.
Manual transmission You can only start the engine when the clutch
pedal is fully depressed.
X Depress the brake pedal and keep it
depressed.
X Depress the clutch pedal fully.
X Shift to neutral N. Driving
159Driving and parking Z

Problem
Possible causes/consequences and
M
MSolutions Vehicles with a petrol
engine:
The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it.
X Have the cause rectified immediately at a qualified specialist
workshop. The coolant tempera-
ture display is showing
more than 120 †. The
coolant warning lamp
may also be on and a
warning tone may
sound. The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant to
cool down.
X Check the coolant level (Y page 326). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the engine radiator fan may be faulty.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. DYNAMIC SELECT button (all vehicles
except Mercedes-AMG vehicles)
Use the DYNAMIC SELECT button to change
the drive program. Depending on the drive
program selected, the following vehicle char- acteristics will change:
R the drive (engine and transmission man-
agement)
R the suspension (vehicles with damping sys-
tem or AMG RIDE CONTROL)
R the steering
R the availability of the ECO start/stop func-
tion
R the climate control
If the ignition is switched off for less than four hours, the previously selected drive program
is activated when the engine is next started. If the ignition is switched off for more than four hours, drive program
Cis activated when the
engine is next started. X
Press DYNAMIC SELECT controller :as
many times as necessary until the desired
drive program is selected.
The selected drive program appears in the
multifunction display. After five seconds
the display goes out and the status icon of the selected drive program appears. 166
DYNAMIC SELECT button (all vehicles except Mercedes-AMG vehicles)Driving and parking

For information on the selector lever in
Mercedes-AMG vehicles (Y page 172).
The DIRECT SELECT lever always returns to
its original position. The current transmission position P,R, Nor Dappears in the transmis-
sion position display in the multifunction dis-
play (Y page 170).
Transmission position and drive pro-
gram display The current transmission position and drive
program appear in the multifunction display.
:
Transmission position
; Gear
= Drive program display
The arrows in the transmission position dis-
play show how and into which transmission
positions you can shift using the DIRECT
SELECT lever.
If the transmission position display in the mul-
tifunction display is not working, you should
pull away carefully to check whether the
desired transmission position is engaged.
Ideally, you should select transmission posi-
tion Dand drive program Eor S.
Engaging park position P !
If the engine speed is too high, do not shift
the automatic transmission directly from D
to R, from Rto Dor directly to P. Otherwise,
the automatic transmission could be dam-
aged. j
Park position with parking lock
k Reverse gear
i Neutral
h Drive
X Push the DIRECT SELECT lever in the direc-
tion of arrow P.
Transmission position display Pis shown in
the multifunction display.
When you have engaged park position P,
make sure that the transmission position dis-
play shows Pin the multifunction display.
You can only engage park position Pwhen the
vehicle is stationary.
Depressing the brake and pushing the
DIRECT SELECT lever up or down disengages the parking lock. The transmission is in neu-
tral N.
At transmission fluid temperatures below
Ò20 †, you can only shift out of park position
P into another transmission position when
the engine is running.
In order to shift from park position Pdirectly
into Ror D:
R depress the brake pedal and
R push the DIRECT SELECT lever up or down
past the first point of resistance 170
Automatic transmissionDriving and parking

Engaging park position P
X
When the vehicle is stationary, press but-
ton :. Transmission positions
B Park position
This prevents the vehicle from roll-
ing away when stopped.
Only shift the transmission into
position Pwhen the vehicle is sta-
tionary (Y page 170). The parking
lock should not be used as a brake when parking. In order to secure
the vehicle, always apply the elec-
tric parking brake in addition to the
parking lock.
In the event of a malfunction of the vehicle's electronics, the transmis-
sion may lock in position P. Have
the vehicle electronics checked
immediately at a qualified special-
ist workshop.
Park position Pis automatically
engaged if:
R you switch off the engine using
the key and remove the key
R you switch off the engine using
the key or using the Start/Stop
button and open the driver's
door or front-passenger door
R you open the driver's door when
the vehicle is stationary or when
driving at a very low speed and
the transmission is in position D
or R C Reverse gear
Only shift the transmission into
position Rwhen the vehicle is sta-
tionary. Automatic transmission
173Driving and parking Z