warning MERCEDES-BENZ A CLASS 2012 Repair Manual

G
WARNING
The head restraints cannot provide the inten-
ded protection unless they are fitted and
adjusted
correctly. There is an increased risk
of injury to the head and neck in the event of
an accident or sudden braking, for example.
Always drive with the head restraints fitted.
Ensure that the centre of the head restraints
support the back of each vehicle occupant's
head at eye level before driving off.
General notes For vehicles with sports seats, you cannot
adjust the head restraints or remove and fit
the rear head restraints.
Adjusting the head restraints manually
Adjusting the head restraint height
X
To raise: pull the head restraint up to the
desired position.
X To lower: press release catch : in the
direction of the arrow and push the head
restraint down to the desired position. Adjusting the head restraint fore-and-aft
position This function allows you to adjust the dis-
tance between the head restraint and the
back of the head.
X
To move forwards:
pull the head restraint
forwards in the direction of the arrow until
it engages.
There are a number of detents.
X To move backwards: press and hold
release button : and push the head
restraint backwards.
X When the head restraint is in the desired
position,

release the button and make sure
that the head restraint is engaged in posi-
tion.
Adjusting the head restraints electri-
cally X
To adjust the head restraint height:
slide
the switch for head restraint adjustment
(Y page 94) up or down in the direction of
the arrow. Seats
95
Seats, steering wheel and mirrors Z

Rear seat head restraints
Adjusting the rear seat head restraint
height
X
To raise: pull the head restraint up to the
desired position.
X To lower: press release catch : and push
the head restraint down until it is in the
desired position.
Removing and fitting the rear seat head
restraints G
WARNING
The head restraints cannot provide the inten-
ded protection unless they are fitted and
adjusted

correctly. There is an increased risk
of injury to the head and neck in the event of
an accident or sudden braking, for example.
Always drive with the head restraints fitted.
Ensure that the centre of the head restraints
support the back of each vehicle occupant's
head at eye level before driving off.
The rear head restraints on the outer seats
can be removed and refitted. X
Fold the seat backrest slightly forwards in
order to remove the head restraint
(Y page 272).
X To remove: pull the head restraint up to
the stop.
X Press release catch : and pull the head
restraint out of the guides.
X To refit: insert the head restraint so that
the
notches on the bar are on the left when
viewed in the direction of travel.
X Push the head restraint down until you hear
it engage in position. Adjusting the 4-way lumbar support
You can adjust the contour of the front seat
backrests individually to provide optimum
support for your back. :
To raise the backrest contour
; To soften the backrest contour
= To lower the backrest contour
? To harden the backrest contour 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 96
Seats
Seats, steering wheel and mirrors

Adjusting the seat backrest side bol-
sters
X
To set the side bolsters of the seat
backrest narrower: press button A.
X To set the side bolsters of the seat
backrest wider: press button B. 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
; To adjust the steering wheel height
= To adjust 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 completely.
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. Mirrors
Rear-view mirror
X
Anti-dazzle mode: pivot anti-dazzle
switch : forwards or back. 98
Mirrors
Seats, steering wheel and mirrors

Exterior mirrors
Adjusting the exterior mirrors G
WARNING
The exterior mirrors reduce the size of the
image. Objects visible in the mirrors are
closer than they appear. You could misjudge
the distance from road users driving behind
you
when changing lanes, for instance. There
is a risk of an accident.
You should therefore always look over your
shoulder to determine the actual distance
from road users driving behind you. X
Make sure that the key is in position 1 or
2 in the ignition lock.
X Press button : for the left-hand exterior
mirror

or button ; for the right-hand exte-
rior mirror.
The indicator lamp in the corresponding
button lights up in red.
The indicator lamp goes out again after
some time. You can adjust the selected
mirror using adjustment button = as long
as the indicator lamp is lit.
X Press adjustment button = up, down, or
to the left or right until you have adjusted
the exterior mirror to the correct position.
You should have a good overview of traffic
conditions.
The convex exterior mirrors provide a larger
field of vision.
After the engine has been started, the exte-
rior mirrors are automatically heated if the
rear window heating is switched on and the outside temperature is low. Heating takes a
maximum of 10 minutes.
i
The exterior mirrors can also be heated
manually by switching on the rear window
heating.
Folding

the exterior mirrors in/out elec-
trically X
Make sure that the key is in position 1 or
2 in the ignition lock.
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
(30

mph) you can no longer fold in the exte-
rior mirrors.
Setting 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 225).
X
Make sure that the key is in position 1 in
the ignition lock.
X Briefly press button :. Mirrors
99
Seats, steering wheel and mirrors Z

Using the memory button
You
can set the front-passenger side exterior
mirror so that you can see the rear wheel on
that side as soon as you engage reverse gear.
You can store this position. This setting can
be stored using memory button M?.
X Make sure that the vehicle is stationary and
that the key is in position 2 in the ignition
lock.
X Press button ; for the exterior mirror on
the front-passenger side.
X Use adjustment button = to adjust the
exterior mirror. You should see the rear
wheel and the kerb in the exterior mirror.
X Press memory button M ?
and one of the
arrows on adjustment button = within
three seconds.
The parking position is stored if the exterior
mirror does not move.
X If the mirror moves out of position, repeat
the steps.
Calling up a stored parking position set-
ting X
Turn the key to position 2 in the ignition
lock.
X Adjust the exterior mirror on the front-
passenger

side with the corresponding but-
ton ( Y page 99).
X Engage reverse gear.
The exterior mirror on the front-passenger
side moves to the stored parking position.
The exterior mirror on the front-passenger
side moves back to its original position:
R as soon as you exceed a speed of
15 km/h
R about ten seconds after you have disen-
gaged reverse gear
R if you press button : for the exterior mir-
ror on the driver's side Memory functions
Storing settings
G
WARNING
If you use the memory function on the driver's
side while driving, the adjustments could
cause

you to lose control of the vehicle. There
is a risk of an accident.
Only use the memory function on the driver's
side while the vehicle is stationary. G
WARNING
If the memory function adjusts the seat, you
and other vehicle occupants – particularly
children – could become trapped. There is a
risk of injury.
While the memory function is making adjust-
ments,

make sure that no one has any part of
their body within the sweep of the seat. If
someone becomes trapped, immediately
release the memory function position button.
The adjustment is stopped. G
WARNING
If children activate the memory function, they
could become trapped, especially if they are
unattended. 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.
With the memory function, you can store up
to three different settings, e.g. for three dif-
ferent people.
The following settings are stored as a single
memory preset:
R position of the seat, backrest and head
restraint
R driver's side: position of the exterior mir-
rors on the driver's and front-passenger
sides Memory functions
101
Seats, steering wheel and mirrors Z

Setting the exterior lighting
Setting options Exterior lighting can be set using the:
R
light switch
R headlamp range control (vehicles with hal-
ogen headlamps only)
(Y page 107)
R combination switch (Y page 107)
R on-board computer (Y page 221)
Light switch Operation
1W
Left-hand parking lamps
2X Right-hand parking lamps
3T Side lamps, licence plate and instru-
ment cluster lighting
4Ã Automatic headlamp mode, control-
led by the light sensor
5L Dipped-beam/main-beam head-
lamps
BR Rear foglamp
CN Foglamp (vehicles with front fog-
lamps only)
If you hear a warning tone when you leave the
vehicle, the lights may still be switched on.
X Turn the light switch to Ã.
The exterior lighting (except the side lamps/
parking lamps) switches off automatically if
you:
R remove the key from the ignition lock
R open

the driver's door with the key in posi-
tion 0. Automatic headlamp mode G
WARNING
When the light switch is set to Ã, the
dipped-beam
headlamps may not be switched
on automatically if there is fog, snow or other
causes of poor visibility due to the weather
conditions such as spray. There is a risk of an
accident.
In such situations, turn the light switch to
L.
The automatic headlamp feature is only an
aid. The driver is responsible for the vehicle's
lighting at all times.
à is the preferred light switch setting. The
light setting is automatically selected accord-
ing to the brightness of the ambient light
(exception: poor visibility due to weather con-
ditions such as fog, snow or spray):
R Key in position 1 in the ignition lock: the
side lamps are switched on or off automat-
ically depending on the brightness of the
ambient light.
R With the engine running: if you have
switched on the daytime driving lights func-
tion in the on-board computer, the daytime
driving lights or the side lamps and dipped-
beam headlamps are switched on or off
automatically depending on the brightness
of the ambient light.
X To switch on automatic headlamp
mode: turn the light switch to Ã.
The daytime driving lights improve the detect-
ability of your vehicle during the day. Here,
the daytime driving lights function must be
switched on via the on-board computer
(Y page 221).
When the dipped-beam headlamps are
switched on, the L indicator lamp in the
instrument cluster lights up and the daytime
driving lights switch off.
Dipped-beam headlamps
When

the ignition is switched on and the light
switch is in position L, the side lamps and
dipped-beam headlamps are switched on Exterior lighting
105
Lights and windscreen wipers Z

The blue
K indicator lamp in the instru-
ment cluster lights up when the main-beam
headlamps are switched on.
X To switch off the main-beam head-
lamps:

move the combination switch back
to its normal position.
The blue K indicator lamp in the instru-
ment cluster goes out.
i Vehicles with Adaptive Highbeam Assist:
when Adaptive Highbeam Assist is active,
it controls activation of the main-beam
headlamps

(Y page 110).
Headlamp flasher X
To switch on: turn the key in the ignition
lock to position 1 or 2,

or start the engine.
X Pull the combination switch in the direction
of arrow =. Hazard warning lamps
The hazard warning lamps switch on auto-
matically if:
R
an airbag is deployed or
R the vehicle decelerates rapidly from a
speed

of more than 70 km/h and comes to
a standstill
X To switch on the hazard warning lamps:
press button :.
All turn signals flash. If you now switch on
a

turn signal using the combination switch, only the turn signal lamp on the corre-
sponding side of the vehicle will flash.
X To switch off the hazard warning
lamps: press button :.
The hazard warning lamps switch off auto-
matically if the vehicle reaches a speed of
over 10 km/h

again after a full brake appli-
cation.
i The hazard warning lamps still operate if
the ignition is switched off. Headlamp cleaning system
If the "Wipe with washer fluid" function is
operated five times ( Y page 117) while the
lights are on and the engine is running, the
headlamps are cleaned automatically. When
you switch off the ignition, the automatic
headlamp

cleaning system is reset and count-
ing is resumed from 0. Intelligent Light System
General notes The Intelligent Light System is a system that
adjusts the headlamps automatically to suit
the

prevailing driving and weather conditions.
It offers advanced functions for improved illu-
mination of the road surface, e.g. depending
on the vehicle speed or weather conditions.
The system includes the active light function,
cornering light function, motorway mode and
extended range foglamps. The system is only
active when it is dark.
You can activate or deactivate the "Intelligent
Light System" using the on-board computer
(Y page 221). 108
Exterior lightingLights and windscreen wipers

the illumination of the edge of the carriage-
way.
Active:
if you are driving at speeds below
70
km/h and you switch on the rear foglamp.
Not active: if you are driving at speeds above
100 km/h or if you switch off the rear foglamp
following activation. Adaptive Highbeam Assist
G
WARNING
Adaptive Highbeam Assist does not recognise
road users:
R who have no lights, e.g. pedestrians
R who have poor lighting, e.g. cyclists
R whose lighting is blocked, e.g. by a barrier
In

very rare cases, Adaptive Highbeam Assist
recognises road users too late or not at all. In
this, or in similar situations, the automatic
main-beam headlamps will not be deactivated
or activated regardless. There is a risk of an
accident.
Always carefully observe the traffic conditions
and switch off the main-beam headlamps in
good time.
You can use this function to set the head-
lamps to change between dipped beam and
main beam automatically. The system recog-
nises vehicles with their lights on, either
approaching from the opposite direction or
travelling in front of your vehicle, and conse-
quently switches the headlamps from main
beam to dipped beam.
The system automatically adapts the dipped-
beam headlamp range depending on the dis-
tance to the other vehicle. Once the system
no longer detects any other vehicles, it reac-
tivates the main-beam headlamps.
The system's optical sensor is located behind
the windscreen near the overhead control
panel. X
To activate: activate the Adaptive High-
beam Assist function using the on-board
computer (Y page 222).
X Turn the light switch to Ã.
X Press the combination switch beyond the
pressure point in the direction of
arrow : (Y page 107).
The _ indicator lamp in the multifunc-
tion

display lights up when it is dark and the
light sensor activates the dipped-beam
headlamps.
If you are driving at speeds above
45 km/h:
The headlamp range is set automatically
depending on the distance between the
vehicle and other road users.
If you are driving at speeds above
55 km/h and no other road users are rec-
ognised:
The main-beam headlamps are switched on
automatically. The K indicator lamp in
the instrument cluster also lights up.
If you are driving at speeds below
45 km/h or other road users are recog-
nised or the roads are adequately lit:
The main-beam headlamps are switched off
automatically. The K indicator lamp in110
Exterior lighting
Lights and windscreen wipers

The interior lighting is activated for a short
time when the key is removed from the igni-
tion lock. You can activate this delayed
switch-off using the on-board computer
(Y page 223).
Manual interior lighting control
X
To switch the front interior lighting on:
set the switch to the c position.
X To switch off the interior lighting: set the
switch to the | position or (if the door
is closed) to the centre position.
X To switch the rear interior lighting on/
off: press the u button.
X To switch the reading lamps on/off:
press the p button. Crash-responsive emergency lighting
The
interior lighting is activated automatically
if the vehicle is involved in an accident.
X To switch off the crash-responsive
emergency lighting: press the hazard
warning lamp button.
or
X Lock and then unlock the vehicle using the
key. Replacing bulbs
Important safety notes
Xenon bulbs G
DANGER
Xenon bulbs are under high voltage. You can
get
an electric shock if you remove the cover
of the xenon bulb and touch the electrical
contacts. There is a risk of fatal injury.
Never touch the parts or the electrical con-
tacts of the xenon bulb. Always have work on
the xenon bulbs carried out at a qualified spe-
cialist workshop. If your vehicle is equipped with xenon bulbs,
you can recognise this by the following: the
cone of light from the xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be
observed, the lights must be switched on
before starting the engine.
Bulbs and lamps are an important aspect of
vehicle

safety. You must therefore make sure
that these function correctly at all times.
Have the headlamp setting checked regularly.
Other bulbs G
WARNING
Bulbs, lamps and plug connectors can
become very hot during use. When replacing
a

bulb, you could burn yourself on these com-
ponents. There is a risk of injury.
Allow these components to cool down before
replacing the bulb.
There are bulbs other than the xenon bulbs
that you cannot replace. Replace only the
bulbs listed (Y page 113). Have the bulbs that
you cannot replace yourself replaced at a
qualified specialist workshop.
If you require assistance replacing bulbs, con-
sult a qualified specialist workshop.
Do not touch the glass tube of new bulbs with
your bare hands. Even minor contamination
can burn into the glass surface and reduce
the service life of the bulbs. Always use a lint-
free cloth or only touch the base of the bulb
when fitting.
Only use bulbs of the correct type.
If the new bulb still does not light up, consult
a qualified specialist workshop.
Bulbs and lamps are an important aspect of
vehicle safety. You must therefore make sure
that these function correctly at all times.
Have the headlamp setting checked regularly. 112
Replacing bulbs
Lights and windscreen wipers

Dipped-beam headlamps (halogen
headlamps)
G
WARNING
These bulbs are pressurised.
They can explode when being changed if:
R they are still hot
R they hit an object when being removed
R they are dropped
There is a risk of injury.
You should wear eye protection and clean
gloves when you are changing a bulb. If nec-
essary,
have bulbs changed at a qualified spe-
cialist workshop. X
Remove the cover in the front wheel arch
(Y page 113).
X Turn housing cover : anti-clockwise and
pull it out.
X Turn bulb holder ;
anti-clockwise and pull
it out.
X Take the bulb out of bulb holder ;.
X Insert the new bulb into bulb holder ;.
X Insert bulb holder ;
into the lamp and turn
it clockwise.
X Align housing cover : and turn it clock-
wise until it engages.
X Replace the cover in the front wheel arch
(Y page 113). Main-beam headlamps and side lamps/
parking lamps (vehicles with halogen
headlamps) G
WARNING
These bulbs are pressurised.
They can explode when being changed if:
R they are still hot
R they hit an object when being removed
R they are dropped
There is a risk of injury.
You should wear eye protection and clean
gloves when you are changing a bulb. If nec-
essary,

have bulbs changed at a qualified spe-
cialist workshop. X
Switch off the lights.
X Open the bonnet.
X Turn housing cover : anti-clockwise and
pull it out.
X Turn bulb ;
anti-clockwise and pull it out.
X Insert the new bulb and engage it to the
stop.
X Align housing cover : and turn it clock-
wise until it engages.114
Replacing bulbs
Lights and windscreen wipers