light MERCEDES-BENZ A-CLASS HATCHBACK 2012 Repair Manual

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 :(Ypage 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 recognised:
The main-beam headlamps are switched on
automatically. The Kindicator lamp in
the instrument cluster also lights up.
If you are driving at speeds below 45 km/h or other road users are recognised or the
roads are adequately lit:
The main-beam headlamps are switched off
automatically. The Kindicator lamp in
the instrument cluster goes out. The _
indicator lamp in the multifunction display
remains lit.
X To deactivate: move the combination
switch back to its normal position.
The _ indicator lamp in the multifunc-
tion display goes out. Headlamps misted up on the inside
The headlamps may mist up on the inside if
there is high atmospheric humidity.
X Switch on the lights and drive off.
The level of moisture diminishes, depend-
ing on the length of the journey and the
weather conditions (humidity and temper-
ature).
If the level of moisture does not diminish:
X Have the headlamps checked at a qualified
specialist workshop. 110
Exterior lightingLights and windscreen wipers

Interior lighting
Overview of interior lighting
Front overhead control panel
:
p To switch the left-hand front reading
lamp on/off
; c To switch the front interior lighting
on
= v To switch the rear interior lighting
on/off
? | To switch the front interior lighting/
automatic interior lighting control off
A p To switch the right-hand front read-
ing lamp on/off
B To switch the automatic interior lighting
control on Rear-compartment overhead control panel
: p To switch the left-hand reading lamp
on/off
; p To switch the right-hand reading
lamp on/off Interior lighting control
Important notes In order to prevent the vehicle's battery from
discharging, the interior lighting functions are automatically deactivated after some time
except for when the key is in position 2in the
ignition lock.
The brightness of the ambient lighting may be set using the on-board computer
(Y page 222).
Automatic interior lighting control X
To switch on: set the switch to centre
position B.
X To switch off: set the switch to the |
position.
The interior lighting automatically switches
on if you:
R unlock the vehicle
R open a door
R remove the key from the ignition lock
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 cposition.
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 ubutton.
X To switch the reading lamps on/off:
press the pbutton. Crash-responsive emergency lighting
The interior lighting is activated automatically
if the vehicle is involved in an accident. Interior lighting
111Lights and windscreen wipers Z

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 112). 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. Overview of bulb replacement – bulbs
You can replace the following bulbs. The
details for the bulb type can be found in the
legend. Halogen headlamps
:
Turn signal lamp: PY 21 W
; Main-beam headlamp/side lamp/park-
ing lamp: H15 55 W/15 W
= Dipped-beam headlamp: H7 55 W 112
Replacing bulbsLights and
windscreen wipers

Vehicles with Intelligent Light System
:
Cornering lamp: H7 55 W Tail lamp (halogen headlamps)
:
Reversing lamp: W 16 W
; Turn signal lamp: PY 21 W
= Tail lamp/brake lamp: W 16 W
? Rear foglamp: W 16 W
A Tail lamp: W 16 W Replacing the front bulbs
Fitting/removing the cover on the front wheel arch You must remove the cover from the front
wheel housing before you can change the
front bulbs. X
To remove: switch off the lights.
X Turn the front wheels inwards.
X Turn rotary knob :through 90°.
Cover ;is released.
X Push cover ;down.
X To fit: push cover ;up.
X Turn rotary knob :through 90°.
Cover ;is locked.
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. Replacing bulbs
113Lights and windscreen wipers Z

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.
Turn signal lamp (halogen headlamps) X
Switch off the lights.
X Open the bonnet.
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 :and turn it clockwise
until it engages.
Cornering lamps (Intelligent Light Sys-
tem) 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. 114
Replacing bulbsLights and windscreen wipers

X
Switch off the lights.
X Open the bonnet.
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. Replacing the rear bulbs
Opening and closing the side trim pan-
els You must open the side trim panel in the lug-
gage compartment before you can replace
the bulbs in the tail lamps. Left-hand side trim panel Right-hand side trim panel
X To open: turn release knob :90° in the
direction of the arrow and remove side trim panel ;.
X To close: insert side trim panel ;and turn
release knob :90° in the opposite direc-
tion to the arrow.
Tail lamps X
Switch off the lights.
X Open the luggage compartment.
X Open the side trim panel (Y page 115). X
Release and remove connector ;.
X Unscrew wing nut :and remove the lamp
cluster. Replacing bulbs
115Lights and windscreen wipers Z

Lamp cluster
X
Remove plastic nut ?using a suitable
item, e.g. a coin.
X Release attachments =.
X Remove the bulb holder from the lamp clus-
ter. Bulb holder
A
Tail lamp/brake lamp
B Reversing lamp
C Rear foglamp
D Tail lamp
E Turn signals
X Tail lamp/brake lamp/rear foglamp/
reversing lamp: remove the correspond-
ing bulb from the bulb holder.
X Insert the new bulb into the bulb holder.
X Turn signal lamp: lightly press the bulb
into the bulb holder, turn it anti-clockwise
and remove it from the bulb holder. X
Insert the new bulb into the bulb holder and
turn it clockwise.
X Secure the bulb holder to attachments =
on the lamp cluster and tighten plastic
nuts ?. X
Insert the lamp cluster into the vehicle and
make sure that it sits correctly in guides F.
X Tighten wing nut ;and re-establish con-
tact with connector :.
X Close the side trim panel (Y page 115). Windscreen wipers
Switching the windscreen wipers on/
off
! Do not operate the windscreen wipers
when the windscreen is dry, as this could
damage the wiper blades. Moreover, dust
that has collected on the windscreen can
scratch the glass if wiping takes place when the windscreen is dry.
If it is necessary to switch on the wind-
screen wipers in dry weather conditions,
always operate them using washer fluid.
! If the windscreen wipers leave smears on
the windscreen after the vehicle has been
washed in an automatic car wash, this may
be due to wax or other residue. Clean the
windscreen with washer fluid after an auto- matic car wash. 116
Windscreen wipersLights and windscreen wipers

Combination switch
1
$ Windscreen wipers off
2 Ä Intermittent wipe, low (rain sensor
set to low sensitivity)
3 Å Intermittent wipe, high (rain sensor
set to high sensitivity)
4 ° Continuous wipe, slow
5 ¯ Continuous wipe, fast
B í Single wipe/ îto wipe the wind-
screen using washer fluid
X Turn the key to position 1or 2in the ignition
lock.
X Turn the combination switch to the corre-
sponding position.
! Vehicles with a rain sensor: if the wind-
screen becomes dirty in dry weather con-
ditions, the windscreen wipers may be acti-
vated inadvertently. This could damage the windscreen wiper blades or scratch the
windscreen.
For this reason, you should always switch
off the windscreen wipers in dry weather.
Vehicles with a rain sensor: in theÄor
Å position, the appropriate wiping fre-
quency is automatically set according to the
intensity of the rain. In the Åposition, the
rain sensor is more sensitive than in the Ä
position, causing the windscreen wipers to
wipe more frequently.
If the wiper blades are worn, the windscreen
will no longer be wiped properly. This could
prevent you from observing the traffic condi-
tions. Replace the wiper blades twice a year,
ideally in spring and autumn. Switching the rear window wiper on/
off Combination switch
:
è Switch
2 ô To wipe with washer fluid
3 ITo switch on intermittent wiping
4 0To switch off intermittent wiping
5 ô To wipe with washer fluid
X Turn the key to position 1or 2in the ignition
lock.
X Turn switch :on the combination switch
to the corresponding position.
When the rear window wiper is switched on,
the icon appears in the instrument cluster. Replacing the wiper blades
Important safety notes G
WARNING
If the windscreen wipers begin to move while
you are changing the wiper blades, you can be trapped by the wiper arm. There is a risk of
injury.
Always switch off the windscreen wipers and
ignition before changing the wiper blades.
! To avoid damaging the windscreen wiper
blades, make sure that you touch only the
wiper arm of the windscreen wiper.
! Never open the bonnet/tailgate if a wiper
arm is folded away from the windscreen/
rear window. Windscreen wipers
117Lights and windscreen wipers Z

Never fold a windscreen wiper arm without
a wiper blade back onto the windscreen/
rear window.
Hold the windscreen wiper arm firmly when you change the wiper blade. If you release
the wiper arm without a wiper blade and it
falls onto the windscreen/rear window, the
windscreen/rear window may be damaged
by the force of the impact.
Mercedes-Benz recommends that you have the wiper blades changed at a qualified
specialist workshop.
Replacing the windscreen wiper blades Removing the wiper blades
X Remove the key from the ignition lock.
X Fold the wiper arm away from the wind-
screen. X
Press both release clips ;.
X Fold wiper blade :in the direction of
arrow =away from wiper arm ?.
X Remove wiper blade :in the direction of
arrow A. Fitting the wiper blades X
Position new wiper blade :with recess B
on lug A.
X Fold wiper blade :in the direction of
arrow =onto the wiper arm, until retaining
clips ;engage in bracket ?.
X Make sure that wiper blade :is seated
correctly.
X Fold the wiper arm back onto the wind-
screen.
Replacing the rear window wiper blade Removing the wiper blades
X
Remove the key from the ignition lock.
X Fold wiper arm :away from the rear win-
dow until it engages.
X Position wiper blade ;at a right angle to
wiper arm :.
X Hold wiper arm :and press wiper
blade ;in the direction of the arrow until
it releases.
X Remove wiper blade ;.118
Windscreen wipersLights and windscreen wipers

Fitting the wiper blades
X Place new wiper blade ;onto wiper
arm :.
X Hold wiper arm :and press wiper
blade ;in the opposite direction to the
arrow until it engages.
X Make sure that wiper blade ;is seated
correctly.
X Position wiper blade ;parallel to wiper
arm :.
X Fold wiper arm :back onto the rear win-
dow. Windscreen wipers
119Lights and windscreen wipers Z