key battery MERCEDES-BENZ A-CLASS HATCHBACK 2015 Owners Manual

Activating/deactivating (on the
centre console) .............................. 149
Remote contro l.............................. 149
Axle load, permissible (trailer tow-
ing) ...................................................... 406 B
Bag hook ............................................ 311
Ball coupling
Folding in ....................................... 233
Folding out ..................................... 232
BAS (Brake Assist System) ................. 70
Battery (key)
Checking .......................................... 86
Important safety notes .................... 85
Replacing ......................................... 86
Battery (vehicle)
Charging ........................................ 347
Display message ............................ 276
Important safety notes .................. 344
Jump starting ................................. 348
Belt
see Seat belts
Belt tensioner
Activation ......................................... 55
Blind Spot Assist
Activating/deactivating (on-
board computer) ............................ 249
Display message ............................ 279
Notes/function .............................. 226
Trailer towing ................................. 228
Bonnet
Active bonnet (pedestrian protec-tion) ............................................... 322
Closing ........................................... 324
Display message ............................ 288
Important safety notes .................. 322
Opening ......................................... 323
Boot lid
see Tailgate
Boot load (maximum) ........................ 404
Brake
EBD .................................................. 77
Brake Assist
see BAS (Brake Assist System)
Brake fluid
Display message ............................ 265 Notes ............................................. 402
Brake force distribution
see EBD (electronic brake force
distribution)
Brake lamps
Adaptive ........................................... 73
Changing bulb s.............................. 128
Display message ............................ 272
Brakes
ABS .................................................. 69
Adaptive Brake Assist ...................... 72
BAS .................................................. 70
Brake fluid (notes) ......................... 402
Display message ............................ 258
Driving tips .................................... 189
Hill start assist ............................... 161
HOLD function ............................... 204
Important safety notes .................. 189
Parking brake ................................ 185
Warning lamp ................................. 294
Breakdown
Where will I find...? ........................ 338
see Flat tyre
see Tow-starting
see Towing away
Brightness control (instrument
cluster lighting) ................................... 30
Buttons on the steering column ...... 239 C
Calling up a fault see Display messages
Car
see Vehicle
Car wash (care) ................................. 329
Care
Automatic car wash ....................... 329
Carpets .......................................... 335
Display ........................................... 334
Exhaust pipe .................................. 333
Exterior lighting ............................. 332
Gear or selector lever .................... 334
High-pressure cleaner .................... 330
Interior ........................................... 334
Matt paintwork .............................. 331
Note s............................................. 329
Paint .............................................. 330 6
Index

H
Hazard warning lamps Display message ............................ 291
Switching on/off ........................... 123
Head restraints
Adjusting ....................................... 109
Adjusting (manually) ...................... 109
Adjusting (rear) .............................. 110
Fitting/removing (rear) .................. 110
Headlamp
Cleaning system (notes) ............... .403
Headlamp flasher .............................. 123
Headlamps
Misting up ...................................... 124
see Automatic headlamp mode
Heating
see Climate control
High-pressure cleaners .................... 330
Hill start assist .................................. 161
HOLD function
Activating ....................................... 205
Deactivating ................................... 205
Display message ............................ 278
Function/notes ............................ .204
Horn ...................................................... 28 I
Ignition lock see Key positions
Immobiliser .......................................... 77
Indicator and warning lamp
Restraint system ............................ 300
Indicator and warning lamps
COLLISION PREVENTION ASSIST
PLUS .............................................. 303
Coolant .......................................... 301
Engine diagnostics ......................... 301
SPORT handling mode ................... 298
Indicator lamps
Display message ............................ 272
see Warning and indicator lamps
Indicators
see Turn signals
Instrument cluster
Overview .......................................... 30
Settings ......................................... 250 Warning and indicator lamps ........... 31
Instrument cluster lighting .............. 238
Interior lighting
Control .......................................... .125
Emergency lighting ........................ 125
Overview ........................................ 124
Reading lamp ................................. 124
Interior motion sensor
Deactivating ..................................... 80
Function .......................................... .79
Priming ............................................ 79
Switching off .................................... 79
ISOFIX child seat securing system ....59 J
Jack Storage location ............................3 39
Using ............................................. 369
Jump starting (engine) ......................348 K
Key Changing the battery ....................... 86
Checking the battery ....................... 86
Convenience closing feature ............ 95
Convenience opening feature .......... 95
Display message ............................ 291
Door central locking/unlocking ....... 83
Emergency key element ................... 85
Important safety notes .................... 82
KEYLESS-GO start function .............. 84
Loss ................................................. 87
Modifying the programming ............. 84
Positions (ignition lock) ................. 157
Problem (malfunction) ..................... 87
Starting the engine ........................ 160
Key positions
Start/Stop button .......................... 157
Key positions (ignition lock) ............ 157
KEYLESS-GO
Convenience closing ........................ 95
Deactivation ..................................... 83
Locking ............................................ 83
Unlocking ......................................... 83
Kickdown
Driving tips ................................... .174 12
Index

X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor sur-
face :or;.
Make sure that you do not touch the inner
surface of the door handle.
X Convenience closing feature: touch
recessed sensor surface ;for an exten-
ded period.
For further information on the convenience closing feature (Y page 95).X
To unlock the tailgate: pull tailgate han-
dle :.
Deactivating and activating If you do not intend to use the vehicle for an
extended period of time, you can deactivate
KEYLESS-GO. The key will then use very little power, thereby conserving battery power. For
the purposes of activation or deactivation,
the vehicle does not have to be nearby. X
To deactivate: press the&button on
the key twice in rapid succession.
The battery check lamp of the key flashes
twice briefly and lights up once, then KEY-
LESS-GO is deactivated (Y page 86).
X To activate: press any button on the key.
or
X Insert the key into the ignition lock.
KEYLESS-GO and all of its associated fea-
tures are available again. KEYLESS-GO start function
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a key
in the vehicle. Changing the settings of the locking
system
You can change the settings of the locking
system. This means that only the driver's door and the fuel filler flap are unlocked when the
vehicle is unlocked. This is useful if you fre-
quently travel alone.
X To change the setting: press and hold
down the %and& buttons simulta-
neously for about six seconds until the bat-
tery indicator lamp flashes twice
(Y page 86).
If the setting of the locking system is changed
within the signal range of the vehicle, press-
ing the &or% button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock: press the%button once.
X To unlock centrally: press the%but-
ton twice.
X To lock centrally: press the&button. 84
KeyOpening and closing

The KEYLESS-GO function is changed as fol-
lows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner sur-
face of the door handle on the front-
passenger door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles.
X To restore the factory settings: press
and hold down the %and& buttons
simultaneously for approximately six sec-
onds until the battery check lamp flashes
twice (Y page 86). Emergency key element
General notes If the vehicle can no longer be unlocked with
the key or KEYLESS-GO, use the emergency
key element.
If you use the emergency key element to
unlock and open the driver's door or the tail-
gate, the anti-theft alarm system will be trig-
gered (Y page 78).
There are several ways to deactivate the
alarm:
X To deactivate the alarm with the key:
press the %or& button on the key.
or X Insert the key into the ignition lock.
or
X To deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the igni-
tion lock. The key must be in the vehicle.
or X Lock or unlock the vehicle using KEYLESS-
GO. The key must be outside the vehicle.
If you unlock the vehicle using the emergency
key element, the fuel filler flap will not be
unlocked automatically. X
To unlock the fuel filler flap: insert the
key into the ignition lock.
Removing the emergency key element X
Push release catch :in the direction of
the arrow and, at the same time, remove
emergency key element ;from the key.
Further information about:
R unlocking the driver's door (Y page 91)
R unlocking the luggage compartment
(Y page 93)
R locking the vehicle (Y page 92)
Inserting the emergency key element X
Push emergency key element ;com-
pletely into the key until it engages and
release catch :is back in its basic posi-
tion. Battery of the key
Important safety notes G
WARNING
Batteries contain toxic and corrosive substan- ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention immediately. Key
85Opening and closing Z

H
Environmental note Batteries contain pollutants.
It is illegal to dispose of them with the household rubbish.
They must be collected sep-
arately and disposed of in anenvironmentally responsible
recycling system. Dispose of batteries in an
environmentally responsible
manner. Take discharged
batteries to a qualified spe-
cialist workshop or to a col-
lection point for used batter-
ies.
Mercedes-Benz recommends that you have
the battery replaced at a qualified specialist
workshop.
Checking the battery X
Press the &or% button.
The battery is working properly if battery
check lamp :lights up briefly.
The battery is discharged if battery check
lamp :does not light up briefly.
X Replace the battery (Y page 86).
i If the key battery is checked within the
signal reception range of the vehicle, press- ing the &or% button:
R locks or
R unlocks the vehicle
i You can obtain a battery from any quali-
fied specialist workshop. Replacing the battery You require a CR 2025 3 V cell battery.
X Take the emergency key element out of the
key (Y page 85). X
Press emergency key element ;into the
opening in the key in the direction of the
arrow until battery tray cover :opens.
When doing so, do not hold cover :shut.
X Remove battery tray cover :. X
Repeatedly tap the key against your palm
until battery =falls out.
X Insert the new battery with the positive ter-
minal facing upwards. Use a lint-free cloth
to do so.
X Make sure that the surface of the battery is
free of lint, grease and other contamina-
tion.
X Insert the front tabs of battery tray cover :
and then press to close it.
X Insert emergency key element into the key
(Y page 85).
X Check the function of all key buttons on the
vehicle. 86
KeyOpening and closing

Problems with the key
Problem
Possible causes/consequences and
M
MSolutions You cannot lock or
unlock the vehicle
using the key. The key battery is discharged or nearly discharged.
X Vehicles without KEYLESS-GO or KEYLESS-GO start func-
tion: try again to lock/unlock the vehicle using the remote con-
trol function of the key. Point the tip of the key at the driver's
door handle from close range and press the %or& but-
ton.
If this does not work: X Check the key battery (Y page 86) and replace it if necessary
(Y page 86).
X Lock (Y page 91) or unlock (Y page 92) the vehicle using the
emergency key element. There is interference from a powerful source of radio waves.
X Vehicles without KEYLESS-GO or KEYLESS-GO start func-
tion: try again to lock/unlock the vehicle using the remote con-
trol function of the key. Point the tip of the key at the driver's
door handle from close range and press the %or& but-
ton.
If this does not work: X Lock (Y page 91) or unlock (Y page 92) the vehicle using the
emergency key element. The key is faulty.
X Lock (Y page 91) or unlock (Y page 92) the vehicle using the
emergency key element.
X Have the key checked at a qualified specialist workshop. You can no longer lock
or unlock the vehicle
using KEYLESS-GO. 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 Lock (Y page 91) or unlock (Y page 92) the vehicle using the
emergency key element. There is interference from a powerful source of radio waves.
X Lock (Y page 91) or unlock (Y page 92) the vehicle using the
emergency key element. Key
87Opening and closing Z

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

AMG Performance Seat
Vehicles with electrically adjustable seats: to adjust the contour of the seat and for
improved lateral support, you can individually adjust the front seats. Adjusting the side bolsters of the seat
cushion
X To set the side bolsters of the seat
cushion narrower: press button:.
X To set the side bolsters of the seat
cushion wider: press button;.
Adjusting the seat backrest side bolsters
X To set the side bolsters of the seat
backrest narrower: press button=.
X To set the side bolsters of the seat
backrest wider: press button?. Switching the seat heating on/off
Switching on/off G
WARNING
If you repeatedly switch on seat heating, the
seat cushion and backrest padding may
become very hot. The health of vehicle occu-
pants with limited temperature sensitivity or a limited ability to react to excessively high
temperatures may be affected or they may
even suffer burn-like injuries. There is a risk of
injury.
Therefore, do not switch on the seat heating
repeatedly. The three red indicator lamps in the button
indicate the heating level you have selected.
The system automatically switches down
from level 3to level 2after approximately
eight minutes.
The system automatically switches from level
2 to level 1after approximately ten minutes.
The system automatically switches off
approximately 20 minutes after it is set to
level 1.
X Turn the key to position 1or 2in the ignition
lock (Y page 157).
X To switch on: press button:repeatedly
until the desired heating level is set.
X To switch off: press button:repeatedly
until all the indicator lamps go out.
i If the battery voltage is too low, the seat
heating may switch off. Seats
111Seats, steering wheel and mirrors Z

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

Folding the exterior mirrors in/out elec-
trically X
Turn the key to position 1or 2in the ignition
lock (Y page 157).
X Briefly press button :.
Both exterior mirrors fold in or out.
i Make sure that the exterior mirrors are
always folded out fully while driving. They
could otherwise vibrate.
i If you are driving faster than 47 km/h, you
can no longer fold in the exterior mirrors.
Resetting the exterior mirrors If the battery has been disconnected or com-
pletely discharged, the exterior mirrors must
be reset. The exterior mirrors will otherwise
not fold in when you select the "Fold in mir-
rors when locking" function in the on-board
computer (Y page 253).
X Turn the key to position 1in the ignition
lock (Y page 157).
X Briefly press button :.
Folding the exterior mirrors in/out
automatically If the "Fold in mirrors when locking" function
is activated in the on-board computer
(Y page 253): R
the exterior mirrors fold in automatically as
soon as you lock the vehicle from the out-
side
R the exterior mirrors fold out again automat-
ically as soon as you unlock the vehicle and
then open the driver's or front-passenger
door
i If the exterior mirrors have been folded in
manually, they do not fold out.
Exterior mirror pushed out of position If an exterior mirror has been pushed out of
position (forwards or backwards), proceed as
follows:
X Vehicles without electrically folding
exterior mirrors: manually move the exte-
rior mirror into the correct position.
X Vehicles with electrically folding exte-
rior mirrors: press and hold the mirror-
folding button (Y page 114) until you hear a
click and the mirror audibly engages into
position.
The mirror housing is engaged again and
you can adjust the exterior mirrors as usual
(Y page 113). Automatic anti-dazzle mirrors
G
WARNING
Electrolyte may escape if the glass of an auto- matic anti-dazzle mirror breaks. Electrolyte is
harmful and causes irritation. It must not
come into contact with your skin, eyes, res-
piratory organs or clothing or be swallowed.
There is a risk of injury.
If you come into contact with electrolyte,
observe the following:
R immediately rinse off electrolyte from your
skin with water.
R immediately and thoroughly rinse electro-
lyte out of eyes using clean water. 114
MirrorsSeats, steering wheel and
mirrors