2012 MERCEDES-BENZ A CLASS check engine

ATA (anti-theft alarm system)
Activating/deactivating ...................69
ATA (Anti-Theft Alarm system)
Function ........................................... 69
Interior motion sensor .....................70
Switching off the alarm .................... 69
Tow-away protection ........................ 70
ATTENTION ASSIST
Activating/deactivating ................. 219
Display message ............................ 245
Function/notes ............................. 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 program ....................156
Overview ........................................ 151
Problem (fault) ............................... 159
Program selector button ................155
Pulling away ................................... 144
Selector lever ................................ 153
Starting the engine ........................ 144
Steering wheel gearshift paddles ...156
Trailer towing ................................. 155Transmission position display 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 Index
5

Problem (malfunction)
.....................56
Recommendations ........................... 58
Suitable positions
............................ 56
Top Tether ....................................... 54
Cigarette lighter ................................ 278
Cleaning Trailer tow hitch ............................. 294
Climate control
Auxiliary heating/ventilation .......... 134
Controlling automatically ...............128
Convenience opening/closing
(air-recirculation mode) ................. 132
Cooling with air dehumidification ..126
Demisting the windows .................. 130
Demisting the windscreen ............. 130
Important safety notes .................. 122
Indicator lamp ................................ 128
Notes on using THERMATIC auto-
matic climate control .....................123
Notes on using THERMOTRONIC
automatic climate control .............. 125
Overview of systems ......................122
Problems with cooling with air
dehumidification ............................ 128
Problem with the rear window
heating .......................................... 132
Setting the air distribution .............129
Setting the airflow ......................... 129
Setting the air vents ......................139
Setting the temperature ................ 128
Switching air-recirculation mode
on/off ............................................ 132
Switching on/off ........................... 126
Switching residual heat on/off ...... 133
Switching the rear window heat-
ing on/off ...................................... 131
Switching the ZONE function on/
off .................................................. 129
THERMATIC automatic climate
control ........................................... 123
THERMOTRONIC (2-zone) auto-
matic climate control .....................125
Cockpit
Overview .......................................... 28
see Instrument cluster COLLISION PREVENTION ASSIST
Activating/deactivating the dis-
tance warning function
..................218
Display message ............................ 230
Operation/notes .............................. 62
COMAND Online
see separate operating instructions
Combination switch ..........................107
Consumption statistics (on-board
computer) .......................................... 211
Convenience closing feature ..............85
Convenience opening/closing (air-
recirculation mode) ........................... 132
Convenience opening feature ............85
Coolant (engine) Checking the level ......................... 288
Display message ............................ 243
Important safety notes .................. 344
Temperature (on-board computer) . 226
Temperature gauge ........................ 208
Warning lamp ................................. 264
Cooling
see Climate control
Cornering lamps
Changing bulbs .............................. 115
Cornering light function
Display message ............................ 239
Function/notes ............................. 109
Crash-responsive emergency light-
ing ....................................................... 112
Cruise control Activation conditions .....................169
Cruise control lever .......................169
Deactivating ................................... 170
Display message ............................ 250
Driving system ............................... 168
Important safety notes .................. 168
LIM indicator lamp .........................169
Selecting ........................................ 169
Setting a speed .............................. 170
Storing and maintaining current
speed ............................................. 169
Cup holder
Centre console .............................. 276
Important safety notes .................. 275
Rear compartment ......................... 276 Index
7

Tow-starting (vehicle) ..................... 314
Warning lamp (engine diagnostics)
264
Engine electronics
Notes ............................................. 336
Problem (fault) ............................... 149
Engine oil
Additives ........................................ 344
Checking the oil level ..................... 286
Checking the oil level using the
dipstick .......................................... 287
Display message ............................ 245
Filling capacity ............................... 343
Notes about oil grades ................... 343
Notes on oil level/consumption .... 286
Temperature (on-board computer) . 226
Topping up ..................................... 287
Viscosity ........................................ 344
Environmental protection
Returning an end-of-life vehicle ....... 21
ESP ®
(Electronic Stability Pro-
gram) AMG menu (on-board computer) ... 226
Deactivating/activating (AMG
vehicles) .......................................... 66
Deactivating/activating (except
AMG vehicles) ................................ 218
Deactivating/activating (notes;
except AMG vehicles) ...................... 68
Display message ............................ 230
ETS/4ETS ........................................ 65
Function/notes ......................... 65, 66
Important safety guidelines .............65
Trailer stabilisation ..........................68
Warning lamp ................................. 260
ETS/4ETS (Electronic Traction Sys-
tem) ...................................................... 65
Exhaust pipe (cleaning instructions) 294
Exterior lighting Settings options ............................. 105
see Lights
Exterior mirrors
Adjusting ......................................... 99
Anti-dazzle mode (automatic) ........ 100
Folding in/out (automatically) ....... 100
Folding in/out (electrically) ............. 99
Folding in when locking (on-board
computer) ...................................... 225
Out of position (troubleshooting) ...100 Parking position .............................
100
Resetting ......................................... 99
Storing settings (memory function)
101 F
Fault message see Display messages


Filler cap
see Fuel filler flap
Fire extinguisher ............................... 299
First-aid kit ......................................... 298
Fitting a wheel Removing a wheel ..........................328
Fitting wheels
Fitting a wheel ............................... 328
Lowering the vehicle ......................329
Preparing the vehicle .....................325
Raising the vehicle ......................... 326
Securing the vehicle against roll-
ing away ........................................ 325
Flat tyre
MOExtended tyres .........................300
Preparing the vehicle .....................300
TIREFIT kit ...................................... 301
see Emergency spare wheel
Floormat ............................................. 281
Foglamps Extended range .............................. 109
Switching on/off ........................... 106
Frequencies
Mobile phone ................................. 336
Two-way radio ................................ 336
Front foglamps
Display message ............................ 241
Fuel
Additives ........................................ 341
Consumption information .............. 342
Consumption statistics ..................211
Displaying the current consump-
tion ................................................ 212
Displaying the range ...................... 212
Fuel gauge ....................................... 30
Grade (petrol) ................................ 340
Important safety notes .................. 339
Notes for AMG vehicles ................. 340
Problem (malfunction) ...................161
Quality (diesel) ............................... 34110
Index

Reading lamp
................................. 111
Setting the ambient lighting
brightness (on-board computer) .... 222
Interior motion sensor ........................70
ISOFIX child seat securing system ....53 J
Jack Storage location ............................ 299
Using ............................................. 326
Jump starting (engine) ...................... 308K
Key Changing the battery ....................... 76
Checking the battery ....................... 76
Convenience closing feature ............ 85
Convenience opening feature .......... 85
Display message
............................ 256
Door central locking/unlocking ....... 75
Emergency key element ................... 75
Important safety notes .................... 74
Loss ................................................. 78
Modifying the programming .............75
Positions (ignition lock) ................. 143
Problem (malfunction) .....................78
Starting the engine ........................ 144
Key positions (ignition lock) ............143
Kickdown Driving tips .................................... 154
Manual drive program ....................158
Kneebag ............................................... 44L
Lamps see Warning and indicator lamps


Lane Keeping Assist
Activating/deactivating ................. 219
Display message ............................ 247
Function/information .................... 199
Lane package ..................................... 197
Lap time (RACETIMER) ......................226
Lashing eyelets ................................. 273
Licence plate lamp (display mes-
sage) ................................................... 241Lighting
see Lights

Lights
Activating/deactivating the Intel-
ligent Light System ........................ 221
Activating/deactivating the inte-
rior lighting delayed switch-off ....... 223
Active light function .......................109
Automatic headlamp mode ............ 105
Cornering light function .................109
Dipped-beam headlamps ............... 105
Display message ............................ 239
Driving abroad ............................... 104
Foglamps ....................................... 106
Foglamps (extended range) ...........109
Hazard warning lamps ................... 108
Headlamp flasher ........................... 108
Headlamp range ............................ 107
Light switch ................................... 105
Main-beam headlamps ................... 107
Motorway mode ............................. 109
Parking lamps ................................ 106
Rear foglamp ................................. 106
Setting the ambient lighting
brightness (on-board computer) .... 222
Side lamps ..................................... 106
Switching Adaptive Highbeam
Assist on/off ................................. 222
Switching the daytime driving
lights on/off (on-board computer) . 221
Switching the daytime driving
lights on/off (switch) ..................... 105
Switching the exterior lighting
delayed switch-off on/off (on-
board computer) ............................ 222
Switching the surround lighting
on/off (on-board computer) ..........222
Turn signals ................................... 107
see Interior lighting
see Replacing bulbs
Light sensor (display message) .......242
LIM indicator lamp Cruise control ................................ 169
DISTRONIC PLUS ........................... 174
Variable SPEEDTRONIC .................171
Limiting the speed
see SPEEDTRONIC
Loading guidelines ............................26812
Index

Outside temperature ...................... 209
Setting (climate control)
................128
TEMPOMAT
Function/notes ............................. 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
Towing Important safety notes .................. 310
Towing a trailer
Active Parking Assist .....................190
Axle load, permissible .................... 349
Bulb failure indicator for LED lamps 206
ESP ®
(Electronic Stability Program) . 68
Pulling away with a trailer ..............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
Tow-starting
Emergency engine starting ............ 314
Fitting the towing eye ....................311
Important safety notes .................. 310
Removing the towing eye ...............312
Trailer coupling
see Towing a trailer
Trailer towing
7-pin connector ............................. 206
Blind Spot Assist ............................ 199
Cleaning the trailer tow hitch ......... 294
Coupling up a trailer ......................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 .................... 348Parktronic ......................................
185
Power supply ................................. 206
Trailer loads ................................... 349
Transmission
see Automatic transmission
see Manual transmission
Transmission position display
(DIRECT SELECT lever) ......................152
Transporting the vehicle .................. 313
Trim pieces (cleaning instructions) . 295
Trip computer (on-board computer) 211
Trip meter Calling up ....................................... 211
Resetting (on-board computer) ...... 213
Turn signals
Changing bulbs (front) ................... 115
Changing bulbs (rear) .................... 116
Switching on/off ........................... 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 wheel .......................... 324
Checking ........................................ 319
Direction of rotation ......................324
Display message ............................ 251
Important safety notes .................. 318
M+S tyres ...................................... 320
MOExtended tyres .........................320
Replacing ....................................... 324
Service life ..................................... 319
Storing ........................................... 324
Summer tyres ........................ 168, 32018
Index

G
WARNING
Objects in the driver's footwell can restrict the
pedal travel or obstruct a depressed pedal.
The operating and road safety of the vehicle
is jeopardised. There is a risk of an accident.
Make sure that all objects in the vehicle are
stowed correctly, and that they cannot enter
the driver's footwell. Fit the floormats
securely and as specified in order to ensure
sufficient
clearance for the pedals. Do not use
loose floormats.
! If the engine is switched off and equip-
ment on the diagnostics connection is
used, the starter battery may discharge.
Connecting equipment to the diagnostics
connection can lead to emissions monitoring
information being reset, for example. This
may lead to the vehicle failing to meet the
requirements of the next emissions test dur-
ing the main inspection. Qualified specialist workshop
A qualified specialist workshop has the nec-
essary special skills, tools and qualifications
to correctly carry out any necessary work on
your

vehicle. This particularly applies to work
relevant to safety.
Observe the notes in the Service Booklet.
Always have the following work carried out at
a qualified specialist workshop:
R work relevant to safety
R service and maintenance work
R repair work
R modifications, installations and conver-
sions
R work on electronic components
Mercedes-Benz recommends that you use a
Mercedes-Benz Service Centre. Vehicle registration
Mercedes-Benz may ask its Service Centres
to carry out technical inspections on certain
vehicles. The quality or safety of the vehicle
is improved as a result of the inspection.
Mercedes-Benz can only inform you about
vehicle

checks if it has your registration data.
It is possible that your vehicle has not yet
been registered in your name in the following
cases:
R if your vehicle was not purchased at an
authorised specialist dealer.
R if your vehicle has not yet been examined
at a Mercedes-Benz Service Centre.
It is advisable to register your vehicle with a
Mercedes-Benz Service Centre.
Inform Mercedes-Benz as soon as possible
about any change in address or vehicle own-
ership. Correct use
If you remove any warning stickers, you or
others

could fail to recognise certain dangers.
Leave warning stickers in position.
Observe the following information when driv-
ing your vehicle:
R the safety notes in this manual
R the technical data in this manual
R traffic rules and regulations
R laws and safety standards pertaining to
motor vehicles Implied warranty
! Follow the instructions in this manual
about the proper operation of your vehicle
as well as about possible vehicle damage.
Damage to your vehicle that arises from
culpable contraventions against these
instructions are not covered either by
Mercedes-Benz implied warranty or by the
New or Used-Vehicle Warranty. 24
Introduction

SRS (Supplemental Restraint System)
Introduction Supplemental Restraint System (SRS) with:
R
The 6 SRS warning lamp
R Airbags
R Airbag control unit (with crash sensors)
R Belt
tensioners for the front seat belts and
the outer seat belts in the rear
R Seat belt force limiters for the front seat
belts and the outer seat belts in the rear
SRS reduces the risk of occupants coming
into contact with parts of the vehicle's interior
in the event of an accident. It can also reduce
the forces to which occupants are subjected
during an accident.
SRS warning lamp G
WARNING
If SRS is malfunctioning, individual systems
may
be triggered unintentionally or might not
be triggered in the event of an accident with
a high rate of vehicle deceleration.
A malfunction has occurred if:
R the 6 SRS warning lamp does not light
up when the ignition is switched on.
R the engine is running and the 6 SRS
warning lamp does not go out after a few
seconds.
R the engine is running and the 6 SRS
warning lamp lights up again.
In this case, have SRS checked immediately
at a qualified specialist workshop.
The 6 SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
SRS functions are checked regularly when the
ignition is switched on or the engine is run-
ning. Therefore, malfunctions can be detec-
ted in good time. Triggering of belt tensioners and air-
bags During the first stage of a collision, the airbag
control unit evaluates important physical
data

relating to vehicle deceleration or accel-
eration, such as:
R duration
R direction
R magnitude
Based on the evaluation of this data, the air-
bag control unit pre-emptively triggers the
belt tensioners in the first stage.
If there is an even higher rate of vehicle decel-
eration or acceleration in a longitudinal direc-
tion, the front airbags are also deployed.
Your vehicle has adaptive, two-stage front air-
bags. The airbag control unit evaluates vehi-
cle deceleration or acceleration in the event
of a collision. In the first deployment stage,
the front airbag is filled with enough propel-
lant gas to reduce the risk of injuries. The
front airbag is fully deployed if a second
deployment threshold is reached within a few
milliseconds.
The belt tensioner and airbag triggering
thresholds are variable and are adapted to the
detected rate of deceleration or acceleration
of the vehicle. This process is pre-emptive in
nature. The triggering process must take
place in good time at the start of the collision.
The rate of vehicle deceleration or accelera-
tion and the direction of the force are essen-
tially determined by:
R the distribution of forces during the colli-
sion
R the collision angle
R the deformation characteristics of the vehi-
cle
R the characteristics of the object with which
the vehicle has collided
Factors which can only be seen and measured
after a collision has occurred do not play a
decisive role in the deployment of an airbag, Occupant safety
41
Safety Z

teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated.
There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y page 258) and
display messages which may be shown in the
instrument cluster (Y page 230).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi-
cle when braking.
ABS works from a speed of about 8 km/h
upwards, regardless of road-surface condi-
tions. ABS works on slippery surfaces, even
when you only brake gently.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Braking X
If ABS intervenes:
continue to depress the
brake pedal with force until the braking sit-
uation is over.
X To make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
The pulsating brake pedal can be an indica-
tion of hazardous road conditions, and func-
tions as a reminder to take extra care while
driving. BAS (Brake Assist)
i Observe

the "Important safety notes" sec-
tion (Y page 61). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
BAS operates in emergency braking situa-
tions.

If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. COLLISION PREVENTION ASSIST
General notes COLLISION PREVENTION ASSIST consists of
the adaptive Brake Assist and the distance
warning signal, which are described in the
following.
Distance warning function
Important safety notes
i
Observe

the "Important safety notes" sec-
tion for driving safety systems
(Y page 61). G
WARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
Thus, the distance warning function cannot
provide a warning in all critical situations.
There is a risk of an accident.
Always

pay careful attention to the traffic sit-
uation and be ready to brake. 62
Driving safety systems
Safety