alarm MERCEDES-BENZ A-CLASS HATCHBACK 2012 Owners Manual

1, 2, 3 ...
4ETS see ETS/4ETS (Electronic Trac-
tion System)
4MATIC (permanent all-wheel
drive)
Display message ............................ 254
4MATIC (permanent four-wheel
drive) .................................................. 182
12 V socket
see Sockets A
ABS (Anti-lock Braking System) Display message ............................ 230
Function/notes ................................ 61
Important safety notes .................... 61
Warning lamp .................................2 58
Activating/deactivating air-recir-
culation mode ................................... .132
Activating/deactivating cooling
with air dehumidification ................. 126
Active light function ......................... 108
Active Parking Assist
Cancelling ...................................... 190
Detecting parking spaces .............. 187
Display message ............................ 248
Exiting a parking space .................. 189
Function/notes ............................ .187
Important safety notes .................. 186
Parking .......................................... 188
Towing a trailer .............................. 190
ADAPTIVE BRAKE ................................. 69
Adaptive Brake Assist
Display message ............................ 237
Function/notes ................................ 63
Adaptive brake lights .......................... 64
Adaptive Highbeam Assist
Display message ............................ 243
Function/notes ............................ .109
Adaptive Main-beam Assist
Switching on/off (on-board com-
puter) ............................................. 222
Additional speedometer ................... 220
Additives (engine oil) ........................ 344
Adjusting the headlamp range ......... 107Air filter (white display message)
.... 245
Air vents
Important safety notes .................. 139
Rear ............................................... 140
Setting .......................................... .139
Setting the centre air vents ........... 139
Setting the side air vents .............. .140
Air vents
see Climate control
Air-conditioning system
see Climate control
Airbags
Front airbag (driver, front
passenger) ....................................... 43
Important safety guidelines ............. 42
Kneebag .......................................... .44
Sidebag ............................................ 44
Triggering ......................................... 41
Windowba g...................................... 45
Alarm system
see ATA (Anti-Theft Alarm system)
Ambient lighting
Setting the brightness (on-board
computer) ...................................... 222
AMG
Menu (on-board computer) ............ 226
Performance Seat ............................ 97
Anti-glare film .................................... 281
Anti-lock braking system
see ABS (Anti-lock Braking System)
Anti-Theft Alarm system
see ATA (Anti-Theft Alarm system)
Aquaplaning ....................................... 167
Ashtray ............................................... 277
Assistance display (on-board com-
puter) .................................................. 217
Assistance menu (on-board com-
puter) .................................................. 217
ASSYST PLUS
Displaying a service message ........ 290
Hiding a service message .............. 289
Notes ............................................. 289
Resetting the service interval dis-
play ................................................ 290
Service message ............................ 289
Special service requirements ......... 290 4
Index

ATA (Anti-Theft Alarm system)
Activating/deactivating .................. .69
Function ........................................... 69
Interior motion senso r..................... 70
Switching off the alarm .................... 69
Tow-away protection ........................ 70
ATTENTION ASSIST
Activating/deactivating ................. 219
Display message ............................ 245
Function/note s............................. 195
Audio menu (on-board computer) .... 214
AUTO lights
Display message ............................ 242
see Lights
Automatic engine start (ECO start/
stop function) .................................... 147
Automatic engine switch-off (ECO
start/stop function) .......................... 146
Automatic headlamp mode .............. 105
Automatic transmission
Accelerator pedal position ............. 154
Automatic drive program ............... 156
Changing gear ............................... 154
DIRECT SELECT lever ..................... 151
Display message ............................ 252
Drive program display .................... 152
Driving tips .................................... 154
Emergency running mode .............. 159
Engaging drive position .................. 153
Engaging neutral ............................ 153
Engaging park position (AMG vehi-
cles) ............................................... 153
Engaging reverse gear ................... 153
Engaging the park position ............ 152
Holding the vehicle stationary on
uphill gradients .............................. 154
Kickdown ....................................... 154
Manual drive progra m.................... 156
Overview ........................................ 151
Problem (fault) ............................... 159
Program selector button ................ 155
Pulling away ................................... 144
Selector lever ................................ 153
Starting the engine ........................ 144
Steering wheel gearshift paddle s... 156
Trailer towing ................................. 155
Transmission position dis-
play ........................................ 152, 153 Transmission positions .................. 153
Automatic transmission emer-
gency running mode ......................... 159
Auxiliary heating
Activating/deactivating ................. 134
Activating/deactivating (on the
centre console ).............................. 135
Display message ............................ 255
Important safety notes .................. 134
Problem (display message) ............ 138
Remote control .............................. 135
Setting ........................................... 224
Setting the departure time ............. 136
Auxiliary ventilation
Activating/deactivating ................. 134
Activating/deactivating (on the
centre console ).............................. 135
Problem (display message) ............ 138
Remote control .............................. 135
Axle load, permissible (trailer tow-
ing) ...................................................... 349 B
Bag hook ............................................ 273
Ball coupling
Folding in ....................................... 205
Folding out ..................................... 203
BAS (Brake Assist System) ................. 62
Battery (key)
Checking .......................................... 76
Important safety notes .................... 76
Replacing ......................................... 76
Battery (vehicle)
Charging ........................................ 306
Display message ............................ 244
Important safety notes .................. 304
Jump starting ................................. 308
Belt force limiter
Activation ......................................... 49
Function ........................................... 49
Belt tensioner
Activation ......................................... 41
Function ........................................... 49
Blind Spot Assist
Activating/deactivating ................. 219
Display message ............................ 247
Notes/function .............................. 198 Index
5

Speed, controlling
see Cruise control
Speedometer
Activating/deactivating the addi-
tional speedometer ........................ 220
Digital ............................................ 212
In the Instrument cluster ................. 30
Segments ...................................... 209
Selecting the unit of measure-
ment ..............................................2 20
see Instrument cluster
SPEEDTRONIC
Deactivating variable ..................... 172
Display message ............................ 250
Function/notes ............................ .171
Important safety notes .................. 171
LIM indicator lamp ......................... 171
Permanent ..................................... 172
Selecting ........................................ 171
Storing the current spee d.............. 172
Variabl e......................................... 171
SPORT handling mode
Activating/deactivating (AMG
vehicles) .......................................... 66
Warning lamp ................................. 261
SRS (Supplemental Restraint Sys-
tem)
Display message ............................ 238
Introduction ..................................... 41
Warning lamp ................................. 263
Warning lamp (function) ................... 41
Start/stop function
see ECO start/stop function
Starting (engine) ................................ 143
STEER CONTROL .................................. 69
Steering (display message) .............. 255
Steering wheel
Adjusting (manually) ........................ 98
Button overview ............................... 33
Buttons (on-board computer) ......... 209
Cleaning ......................................... 295
Gearshift paddle s........................... 156
Important safety notes .................... 98
Steering wheel gearshift paddles .... 156
Stopwatch (RACETIMER) ................... 226
Stowage areas ................................... 269 Stowage compartments
Armrest (front) ............................... 270
Armrest (under) ............................. 270
Centre console .............................. 269
Centre console (rear) ..................... 271
Cup holde r..................................... 275
Glove compartment ....................... 269
Important safety information ......... 269
Luggage net ................................... 271
Spectacles compartment ............... 269
Under driver's seat/front-
passenger sea t.............................. 270
Summer tyres .................................... 320
Sun visor ............................................ 277
Supplemental Restraint System
see SRS (Supplemental Restraint
System)
Surround lighting (on-board com-
puter) .................................................. 222
Switching off the alarm (ATA) ............ 69 T
Tail lamps Display message ............................ 241
see Lights
Tailgate
Display message ............................ 254
Emergency unlocking ....................... 83
Important safety notes .................... 82
Opening dimensions ...................... 346
Opening/closing (from outside) ....... 82
Technical data
Capacities ...................................... 338
Emergency spare whee l................. 333
Information .................................... 336
Trailer load s................................... 349
Tyres/wheels ................................. 329
Vehicle data ................................... 346
Telephone
Accepting a call ............................. 216
Display message ............................ 256
Menu (on-board computer) ............ 215
Number from the phone book ........ 216
Redialling ....................................... 217
Rejecting/ending a call ................. 216
Telephone compartment ................ 270 Index
17

Temperature
Coolant .......................................... 208
Coolant (on-board computer) ......... 226
Engine oil (on-board computer) ...... 226
Outside temperature ...................... 209
Setting (climate control) ................ 128
TEMPOMAT
Function/note s............................. 168
Theft-deterrent system
ATA (Anti-Theft Alarm system) ......... 69
Immobiliser ...................................... 69
Through-loading ................................ 271
Time
see Separate Owner's manual
Timing (RACETIMER) ......................... 226
TIREFIT kit .......................................... 301
Top Tether ............................................ 54
Tow-away protection .......................... 70
Tow-starting
Emergency engine starting ............ 314
Fitting the towing eye .................... 311
Important safety notes .................. 310
Removing the towing eye ............... 312
Towing
Important safety notes .................. 310
Towing a trailer
Active Parking Assist ..................... 190
Axle load, permissibl e.................... 349
Bulb failure indicator for LED
lamps ............................................. 206
ESP® (Electronic Stability Pro-
gram) ............................................... 68
Pulling away with a traile r.............. 145
Trailer tow hitch display message .. 255
Towing away
Fitting the towing eye .................... 311
Removing the towing eye ............... 312
With both axles on the ground ....... 312
With front axle raised ..................... 312
Trailer coupling
see Towing a trailer
Trailer towing
7-pin connecto r............................. 206
Blind Spot Assist ............................ 199
Cleaning the trailer tow hitch ......... 294
Coupling up a traile r...................... 204
Decoupling a trailer ....................... 204 Driving tips .................................... 201
Folding in the ball coupling ............ 205
Folding out the ball coupling .......... 203
Important safety notes .................. 201
Lights display message .................. 239
Mounting dimensions .................... 348
Parktronic ...................................... 185
Power supply ................................. 205
Trailer load s................................... 349
Transmission
see Automatic transmission
see Manual transmission
Transmission position display
(DIRECT SELECT lever) ...................... 152
Transporting the vehicle .................. 313
Trim pieces (cleaning instruc-
tions) .................................................. 295
Trip computer (on-board com-
puter) .................................................. 211
Trip meter
Calling up ....................................... 211
Resetting (on-board computer) ...... 212
Turn signals
Changing bulbs (front) ................... 114
Changing bulbs (rear) .................... 115
Switching on/of f........................... 107
TV
Operating (on-board computer) ..... 215
see Separate operating instructions
Two-way radio
Frequencies ................................... 336
Installation ..................................... 336
Transmission output (maximum) .... 336
Type identification plate
see Vehicle identification plate
Tyre pressure
Display message ............................ 251
Not reached (TIREFIT) .................... 303
Reached (TIREFIT) .......................... 303
Recommended ............................... 321
Tyre pressure loss warning
Important safety notes .................. 323
Restarting ...................................... 323
Tyres
Changing a whee l.......................... 324
Checking ........................................ 319
Direction of rotation ...................... 324
Display message ............................ 251 18
Index

Observe information regarding indicator and
warning lamps (Y page 258) as well as dis-
play messages (Y page 232).
EBD monitors and controls the brake pres-
sure on the rear wheels to improve driving
stability while braking. ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In addi-
tion to the braking function, ADAPTIVE BRAKE
also has the HOLD function (Y page 180) and
hill start assist (Y page 145). For further
information, see Driving tips (Y page 166).STEER CONTROL
STEER CONTROL helps you by transmitting a noticeable steering force to the steering
wheel in the direction required for vehicle
stabilisation.
This steering support is provided in particular
if:
R both right wheels or both left wheels are on
a wet or slippery road surface when you
brake
R the vehicle starts to skid.
If there is an ESP ®
malfunction, you will not
receive any steering support from STEER
CONTROL. Power steering will, however, con-
tinue to function. Anti-theft systems
Immobiliser
The immobiliser prevents your vehicle from
being started without the correct key.
X To activate: remove the key from the igni-
tion lock.
X To deactivate: switch on the ignition.
When leaving the vehicle, always take the key
with you and lock the vehicle. The engine can be started by anyone with a valid key that is
left inside the vehicle.
i The immobiliser is always deactivated
when you start the engine. ATA (Anti-Theft Alarm system)
X
To prime: lock the vehicle with the key.
Indicator lamp :flashes. The alarm sys-
tem is primed after approximately
15 seconds.
X To deactivate: unlock the vehicle with the
key.
or X Insert the key into the ignition lock.
A visual and audible alarm is triggered if the
alarm system is primed and you open: R the vehicle with the emergency key ele-
ment
R a door
R the tailgate
R the bonnet
X To stop the alarm: insert the key into the
ignition lock.
The alarm is switched off.
or X Press the %or& button on the key.
The alarm is switched off.
The alarm is not switched off, even if you
close the open door that has triggered it, for
example. Anti-theft systems
69Safety Z

Tow-away protection
Function An audible and visual alarm is triggered if your
vehicle's angle of inclination is altered while
tow-away protection is primed. This can occur
if the vehicle is jacked up on one side, for
example.
Activating X
Make sure that:
R the doors are closed.
R the tailgate is closed.
Only then is the tow-away protection
primed.
X Lock the vehicle with the key.
Tow-away protection is primed after
approximately 60 seconds.
Deactivating X
Unlock the vehicle with the key.
or X Insert the key into the ignition lock.
Tow-away protection is switched off auto-
matically.
Deactivating X
Remove the key from the ignition lock.
X Press button :.
Indicator lamp ;lights up briefly.
X Lock the vehicle with the key.
Tow-away protection is deactivated. Tow-away protection remains deactivated
until:
R the vehicle is unlocked again
R a door is opened and closed again
R the vehicle is locked again
To prevent a false alarm, deactivate the tow-
away protection if you lock your vehicle and it:
R is being transported
R is being loaded onto a ferry or car trans-
porter, for example
R is parked on a movable surface, e.g. in a
split-level garage Interior motion sensor
Function When the interior motion sensor is primed, a
visual and audible alarm is triggered if move-
ment is detected in the vehicle interior. This
can occur if someone reaches into the vehicle interior, for example.
Activating X
Make sure that:
R the side windows are closed.
R the panorama sliding sunroof is closed.
R there are no objects, e.g. mascots, hang-
ing on the rear-view mirror or on the grab
handles on the roof trim.
This will prevent false alarms.
X Make sure that:
R the doors are closed.
R the panorama sliding sunroof is closed.
R the tailgate is closed.
Only then is the interior motion sensor
primed.
X Lock the vehicle with the key.
The interior motion sensor is primed after
approximately 30 seconds. 70
Anti-theft systemsSafety

Deactivating
X
Unlock the vehicle with the key.
or
X Insert the key into the ignition lock.
The interior motion sensor is switched off
automatically.
Deactivating X
Remove the key from the ignition lock.
X Press button :.
Indicator lamp ;flashes briefly.
X Lock the vehicle with the key.
The interior motion sensor is deactivated.
The interior motion sensor remains deactiva-
ted until:
R the vehicle is unlocked again
R a door is opened and closed again
R the vehicle is locked again
To prevent a false alarm, deactivate the inte-
rior motion sensor if you lock your vehicle
and:
R people or animals remain in the vehicle.
R the panorama sliding sunroof remains
open.
R the side windows remain open.
i UK only:
your vehicle is equipped with a
double lock function. The doors cannot be
opened from the inside if the vehicle has
been locked with the key (Y page 80).
Deactivate the interior motion sensor
before you lock the vehicle with the key.
The doors can then be opened from the inside after the vehicle has been locked
from the outside with the key. Observe the
"Important safety notes" (Y page 79). Anti-theft syste
ms
71Safety Z

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). Key
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle, they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shift the automatic transmission out of
parking position P.
R shift the 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 or animals unattended in the vehicle.Always keep the key out of reach of children. G
WARNING
If persons (particularly children) are exposed
to heat or cold for a prolonged period, there is a risk of serious or even fatal injuries. Never
leave persons (particularly children) unatten-
ded in the vehicle. G
WARNING
If you attach heavy or large objects to the key, the key could be unintentionally turned in the
ignition lock. This could cause the engine to
be switched off. There is a risk of an accident.
Do not attach any heavy or large objects to the
key. Remove any bulky keyrings before insert-
ing the key into the ignition lock.
! Keep the key away from strong magnetic
fields. Otherwise, the remote control func-
tion could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not keep the key: R with electronic devices, e.g. a mobile
phone or another key
R with metallic objects, e.g. coins or metal
film
R inside metallic objects, e.g. a metal case
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked with the key,
then the double lock function is activated as
standard. You can deactivate the double lock
function by deactivating the interior motion
sensor (Y page 70). The doors can then be
opened from the inside after the vehicle has
been locked from the outside. The anti-theft
alarm system is triggered if the door is
opened from the inside. Switch off the alarm
(Y page 69). 74
KeyOpening and closing

Key functions
:
& To lock the vehicle
; % To unlock the vehicle
X To unlock centrally: press button;.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
R the vehicle is locked again.
R the anti-theft system is primed again.
X To lock centrally: press button:.
The key centrally locks/unlocks: R the doors
R the tailgate
R the fuel filler flap
When unlocking, the turn signals flash once.
When locking, they flash three times.
i When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 222).
i You can also set an audible signal to con-
firm that the vehicle has been locked. The
audible signal can be activated and deacti-
vated using the on-board computer
(Y page 223). 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 on your own.
X To change the setting: press and hold
down the %and& buttons simulta-
neously for approximately six seconds until
battery check lamp (Y page 76) flashes
twice.
i If the setting of the locking system is
changed within the signal range of the vehi- cle, pressing the &or% button:
R locks or
R unlocks the vehicle
The key now functions as follows:
X To unlock the driver's door: press the
% button once.
X To unlock centrally: press the%but-
ton twice.
X To lock centrally: press the&button.
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 76). Emergency key element
General notes If the vehicle can no longer be unlocked with
the key, use the emergency key element.
If you use the emergency key element to
unlock and open the driver's door, the anti-
theft alarm system will be triggered
(Y page 69).
There are several ways to turn off the alarm:
X Press the %or& button on the key.
or X Insert the key into the ignition lock. Key
75Opening and closing Z

alarm system is triggered if the door is
opened from the inside. Switch off the alarm
(Y page 69). Unlocking and opening the doors
from the inside
X
Pull door handle ;.
If the door is locked, locking knob :pops
up. The door is unlocked and can be
opened.
For all countries except the United King-
dom:
You can open a door from inside the vehicle
even if it has been locked.
If the vehicle has previously been locked with
the key, opening a door from the inside will
trigger the anti-theft alarm system. Switch off
the alarm (Y page 69).
You can only open the rear doors from inside the vehicle if they are not secured by the
child-proof locks (Y page 60).
Only for the United Kingdom: if the vehicle
has been locked with the key, the double lock
function is activated as standard. It is then not
possible to open the doors from inside the
vehicle. Deactivate the interior motion sensor (Y page 70) before you lock the vehicle with
the key. The doors can then be opened from
the inside after the vehicle has been locked
from the outside. The anti-theft alarm system
is triggered if the door is opened from the
inside. Switch off the alarm (Y page 69). Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside. This can be useful if you wish to lock the vehicle before pulling away, for
example. X
To unlock: press button :.
X To lock: press button ;.
If all the doors and the tailgate are closed,
the vehicle locks.
This does not lock or unlock the fuel filler flap. You cannot unlock the vehicle centrally from
the inside if the vehicle has been locked with
the key.
For all countries except the United King-
dom: you can open a door from inside the
vehicle even if it has been locked.
If the vehicle has previously been locked with the key, opening a door from the inside will
trigger the anti-theft alarm system. Switch off
the alarm (Y page 69).
Only for the United Kingdom: if the vehicle
has been locked with the key, the double lock
function is activated as standard. It is then not
possible to open the doors from inside the
vehicle. Deactivate the interior motion sensor (Y page 70) before you lock the vehicle with
the key. The doors can then be opened from
the inside after the vehicle has been locked
from the outside. The anti-theft alarm system is triggered if the door is opened from the
inside. Switch off the alarm (Y page 69).80
DoorsOpening and closing