lock MERCEDES-BENZ B-CLASS 2012 Workshop Manual

The blue
K indicator lamp in the
instrument cluster lights
up when the high-
beam headlamps are switched on.
X To switch off the high-beam
headlamps: move the combination

switch
back to its normal position.
The blue K indicator lamp in the
instrument cluster goes out.
i Vehicles with Adaptive Highbeam Assist:
when Adaptive Highbeam Assist is active,
it controls activation of the high-beam
headlamps (Y page 102).
High-beam flasher X
To switch on: turn the SmartKey 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 automatically
switch on if:
R
an air bag is deployed
R the vehicle decelerates rapidly from a
speed of
more

than 45mph (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
corresponding side
of

the vehicle will flash.
X To switch off the hazard warning
lamps: press button :.
The hazard warning lamps switch off
automatically if the vehicle reaches a speed
of over 6mph (10km/h) again after a full
brake application.
i The hazard warning lamps still operate if
the ignition is switched off. Headlamp cleaning system
The headlamps are cleaned automatically if
the "Wipe with washer fluid" function is
operated five times

while the lights are on and
the engine is running (Y page 111). When you
switch off the ignition, the automatic
headlamp cleaning system is reset and
counting is resumed from 0. Cornering light function
The cornering light function improves the
illumination of the road over a wide angle in
the direction
you

are turning, enabling better
visibility in tight bends, for example. The
cornering light function can only be activated
when the low-beam headlamps are switched
on. Exterior lighting
101
Lights and windshield wipers Z
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Active:
R
if you are driving at speeds below 25 mph
(40 km/h )
and switch on the turn signal or
turn the steering wheel.
R if you are driving at speeds between
25 mph (40 km/h) and 45 mph (70 km/h)
and turn the steering wheel.
Not active: if you are driving at speeds above
25 mph (40 km/h) or switch off the turn
signal or turn the steering wheel to the
straight-ahead position.
The cornering lamp may remain lit for a short
time, but is automatically switched off after
no more than three minutes. Extended range fog lamps
The extended range fog lamps reduce the
glare experienced by the driver and improve
the illumination of the edge of the road.
Active:
if you are driving at speeds below
40 mph (70

km/h) and you switch on the rear
fog lamp.
Not active: if, following activation, you are
driving at speeds above 60 mph (100 km/h)
or if you switch off the rear fog lamp. Adaptive Highbeam Assist
G
WARNING
Adaptive Highbeam Assist does not recognize
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
may fail to recognize other road users that
have lights, or may recognize them too late.
In this or similar situations, the automatic
high-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 high-beam headlamps in
good time.
You can use this function to set the
headlamps to change between low beam and
high beam automatically. The system
recognizes vehicles with their lights on, either
approaching from the opposite direction or
traveling in front of your vehicle, and
consequently switches the headlamps from
high beam to low beam.
The system automatically adapts the low-
beam headlamp range depending on the
distance to the other vehicle. Once the
system no longer detects any other vehicles,
it reactivates the high-beam headlamps.
The system's optical sensor is located behind
the windshield near the overhead control
panel. 102
Exterior lighting
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?
| To switch the front interior lighting/
automatic interior lighting control off
A p To switch the right-hand front
reading lamp on/off
B To switch the automatic interior lighting
control on Rear-compartment overhead control panel
:
To switch the 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
unless the SmartKey is in position 2 in the
ignition lock.
The brightness of the ambient lighting may be
set using the on-board computer
(Y page 197).
Automatic interior lighting control X
To switch on: set the switch to center
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 SmartKey from the ignition
lock. The interior light is activated for a short while
when the SmartKey is removed from the
ignition lock. You can activate this delayed
switch-off using the on-board computer
(Y page 198).
Manual interior lighting control
X
To switch the front interior lighting on:
set the switch to the c position.
X To switch the interior lighting off: set the
switch to the |

position or (if the door
is closed) to the center position.
X To switch the 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 carry a 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
contacts of the

Xenon bulb. Always have work
on the Xenon bulbs carried out at a qualified
specialist workshop. 104
Replacing bulbs
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Tail lamp (halogen headlamps)
:
Tail lamp/turn signal lamp/brake lamp:
P 21 W
; Inoperative
= Side marker lamp: P 21 W
? Rear fog lamp: P 21 W
A Backup lamp: W 16 W Tail lamp (Bi-Xenon headlamps)
:
Turn signal lamp/brake lamp: P 21 W
; Rear fog lamp: H 21 W
= Backup lamp: W 16 W License plate lamp (vehicles with halogen
headlamps)
:
License plate lamp: C 5 W Changing the front bulbs
Removing and installing
the cover in the
front wheel housing 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 install: push cover ; up.
X Turn rotary knob : through 90°.
Cover ; is locked.106
Replacing bulbs
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Low-beam headlamps (halogen
headlamps)
G
WARNING
These bulbs are pressurized.
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
necessary, have bulbs changed at a qualified
specialist workshop. X
Remove the cover in the front wheel
housing ( Y page 106).
X Turn housing cover : counter-clockwise
and pull it out.
X Turn bulb holder ; counter-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
clockwise until it engages.
X Replace the cover in the front wheel
housing ( Y page 106). High-beam headlamps (halogen
headlamps) G
WARNING
These bulbs are pressurized.
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
necessary, have bulbs changed at a qualified
specialist workshop. X
Switch off the lights.
X Open the hood.
X Turn housing cover : counter-clockwise
and pull it out.
X Turn bulb holder ; counter-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
clockwise until it engages. Replacing bulbs
107
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Parking lamps/standing lamps
(halogen headlamps)
X
Switch off the lights.
X Open the hood.
X Turn housing cover : counter-clockwise
and pull it out.
X Pull out bulb holder ;.
X Take the bulb out of bulb holder ;.
X Insert the new bulb into bulb holder ;.
X Insert bulb holder ;.
X Align housing cover : and turn it
clockwise until it engages.
Turn signals (halogen headlamps) X
Switch off the lights.
X Open the hood.
X Turn bulb holder : counter-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 light function (Intelligent
Light System) G
WARNING
These bulbs are pressurized.
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
necessary, have bulbs changed at a qualified
specialist workshop. X
Switch off the lights.
X Open the hood.
X Turn housing cover : counter-clockwise
and pull it out.
X Turn bulb holder ; counter-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
clockwise until it engages.108
Replacing bulbs
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Changing the rear bulbs
Opening and closing the side trim
panels You must open the side trim panel in the
cargo compartment before you can change
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
direction to the arrow. Tail lamps Turn signal lamp/tail lamp and brake
lamp
X
Switch off the lights.
X Open the cargo compartment.
X Open the side trim panel ( Y page 109). X
Press retaining lugs : simultaneously in
the direction of

the arrow and pull the bulb
holder out. Bulb holder
:
Tail lamp/brake lamp 3
; Inoperative lamps (vehicles without LEDs)
= Side marker lamp (vehicles without LEDs)
X Lightly press the corresponding bulb into
the holder, turn it counter-clockwise and
remove it from the bulb holder.
X Insert the corresponding new bulb into the
bulb holder and turn it clockwise.
3 Vehicles with LEDs: turn signal/brake light only. Replacing bulbs
109
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Bulb holder
X
Rear fog lamp G: lightly press the
corresponding bulb into holder E, turn it
counter-clockwise and
remove
it from bulb
holder E.
X Insert the new bulb into bulb holder E and
turn it clockwise.
X Backup lamp H: remove the bulb from
bulb holder E

.
X Insert the new bulb into bulb holder E.
X Re-insert bulb holder E until you hear
engage audibly.
X Position trim D and engage it in place by
tapping it with your hand.
X Before beginning the installation, check
that all the metal clips are inserted in the
parts placed to one side: 2 clips ; in the
upper part of handle = and 5 clips A in
trim B.
X If not, remove the missing metal clips from
the metal openings in the tailgate and
insert them in the appropriate places.
X Take trim B and connect plug connector
C to the surround lighting.
i The surround lighting only illuminates
when the tailgate has been shut and
reopened. X
Position trim B and engage it in place by
tapping it
with

your hand, starting from the
outside.
X Clip in the lower section of handle : again.
X Insert and engage the upper section of
handle = into lower section

:.
License plate lamp X
Switch off the lights.
X Open the tailgate.
X Position a screwdriver on lamp lens :
from the outside.
X Lever out lamp lens : and remove it.
X Replace the bulb.
X Insert lamp lens : into the license plate
lamp and press it in until it engages. Windshield wipers
Switching the windshield wipers on/
off
! Do not operate the windshield wipers
when the windshield is dry, as this could
damage the wiper blades. Moreover, dust
that has collected on the windshield can
scratch the glass

if wiping takes place when
the windshield is dry.
If it is necessary to switch on the windshield
wipers in dry weather conditions, always
use washer fluid when operating the
windshield wipers. Windshield wipers
111
Lights and windshield wipers Z
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!
If the windshield wipers leave smears on
the windshield after the vehicle has been
washed in an automatic car wash, wax or
other residues may be the reason for this.
Clean the windshield using washer fluid
after washing the vehicle in an automatic
car wash. Combination switch
1
$ Windshield wiper 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/ î To wipe the
windshield using washer fluid
X Switch on the ignition.
X Turn the combination switch to the
corresponding position.
! Vehicles with a rain sensor: if the
windshield becomes dirty in dry weather
conditions, the windshield wipers may be
activated inadvertently. This could then
damage the windshield wiper blades or
scratch the windshield.
For this reason, you should always switch
off the windshield wipers in dry weather.
Vehicles with
a

rain sensor: in the Ä or
Å position, the appropriate wiping
frequency is automatically set according to
the intensity of the rain. In the Å position,
the rain sensor is more sensitive than in the Ä position, causing the windshield
wipers to wipe more frequently.
If the wiper blades are worn, the windshield
will no longer be wiped properly. This could
prevent you from observing the traffic
conditions. Replace the wiper blades twice a
year, ideally in spring and fall.
Switching the rear window wiper on/
off
Combination switch
:
è Switch
2 ô To wipe with washer fluid
3 I To switch on intermittent wiping
4 0 To switch off intermittent wiping
5 ô To wipe with washer fluid
X Turn the SmartKey to position 1 or
2
in 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 windshield wipers begin to move while
you are changing

the wiper blades, you could
be trapped by the wiper arm. There is a risk
of injury. 112
Windshield wipers
Lights and windshield wipers
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Always switch off the windshield wipers and
ignition before changing the wiper blades.
! To avoid damaging the wiper blades,
make sure that you touch only the wiper
arm of the wiper.
! Never open the hood/tailgate if a wiper
arm has been folded away from the
windshield/rear window.
Never fold a windshield wiper arm without
a wiper blade back onto the windshield/
rear window.
Hold the windshield
wiper arm firmly when
you change the wiper blade. If you release
the wiper arm without a wiper blade and it
falls onto the windshield/rear window, the
windshield/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.
Changing the windshield wiper blades Removing the wiper blades
X
Remove the SmartKey from the ignition
lock.
X Fold the wiper arm away from the
windshield. 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. Installing 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
windshield.
Replacing the rear window wiper blade Removing a wiper blade
X
Remove the SmartKey from the ignition
lock.
X Fold wiper arm : away from the rear
window until it engages.
X Position wiper blade ; at a right angle to
wiper arm :. Windshield wipers
113
Lights and windshield wipers Z
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