headlamp MERCEDES-BENZ B-CLASS 2012 User Guide

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
Lights and windshield wipers
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X
To activate: activate the Adaptive
Highbeam Assist function using the on-
board computer ( Y page 197).
X Turn the light switch to Ã.
X Press the combination switch beyond the
pressure point in
the direction of arrow :
(Y page 100).
The _ indicator lamp in the
multifunction display lights up if it is dark
and the light sensor activates the low-beam
headlamps.
If you are driving at speeds above
approximately 28 mph (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
approximately 35 mph (55 km/h) and no
other road users have been detected:
The high-beam headlamps are switched on
automatically. The K indicator lamp in
the instrument cluster also lights up.
If you are driving at speeds below
approximately 30 mph (45 km/h) or other
road users have been detected or the roads
are adequately lit: The high-beam headlamps are switched off
automatically. The
K indicator 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
multifunction display goes out. Headlamps fogged up on the inside
The headlamps may fog up on the inside if
there is high atmospheric humidity.
X Switch on the lights and drive off.
The level of moisture diminishes,
depending on the

length of the journey and
the weather conditions (humidity and
temperature).
If the level of moisture does not diminish:
X Have the headlamps checked at a qualified
specialist workshop. 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 on/off Interior lighting
103
Lights and windshield wipers Z
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If your vehicle is equipped with Xenon bulbs,
you can recognize 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 connectors can get very hot
when operating. If you change a bulb, you
could burn yourself on these components.
There is a risk of injury.
Allow these components

to cool down before
changing a bulb.
There are bulbs other than the Xenon bulbs
that you cannot replace. Replace only the
bulbs listed (Y page 105). Have the bulbs that
you cannot replace yourself changed at a
qualified specialist workshop.
If you require assistance changing bulbs,
consult 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 installing.
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: changing bulbs/bulb types
You can change

the following bulbs. The bulb
type can be found in the legend. Halogen headlamps
:
Turn signal lamp:3457
; High-beam headlamp: H7 55 W
= Parking lamp/standing lamp: W 5 W LL
? Low-beam headlamp: H7 55 W Vehicles with Intelligent Light System
:
Cornering lamp: H7 55 W Replacing bulbs
105
Lights and windshield wipers Z
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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
Lights and windshield wipers
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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
Lights and windshield wipers Z
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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
Lights and windshield wipers
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Activating/deactivating surround
lighting and exterior lighting delayed
switch-off
If you have activated the
Locator
Lighting: function
and
the light switch is set
to Ã, the following functions are activated
when it is dark:
R surround lighting: the exterior lighting
remains lit for 40 seconds after unlocking
with the SmartKey. If you start the engine,
the surround lighting is switched off and
automatic headlamp mode is activated
(Y page 99).
R exterior lighting delayed switch-off: the
exterior lighting remains lit for
60 seconds after the engine is switched off.
If you close all the doors and the trunk lid,
the exterior lighting goes off after
15 seconds.
X Press the = or ; button on the
steering wheel to select the Sett. menu.
X Press the :
or 9
button to select the
Lights submenu.
X Press a to confirm.
X Press the : or 9
button to select the
Locator Lighting function.
You will see the selected setting: Enabled
or Disabled.
X Press the a button to save the setting.
Deactivating delayed switch-off of the
exterior lighting temporarily:
X Before leaving the vehicle, turn the
SmartKey to position 0

in the ignition lock.
X Turn the SmartKey to position 2 in the
ignition lock.
The exterior lighting delayed switch-off is
deactivated.
Delayed switch-off of the exterior lighting is
reactivated the next time you start the
engine.
i Depending on your vehicle's equipment,
when the surround lighting and delayed
switch-off exterior lighting are on, the
following light up: R
Parking lamps
R Front fog lamps
R Low-beam headlamps
R Daytime running lamps
R Side marker lamps
R Surround lighting in the exterior mirrors
Activating/deactivating the interior
lighting delayed switch-off
If you activate the Interior Lighting
Delay function, the interior lighting remains
on for 20seconds after you remove the
SmartKey from the ignition lock.
X Press the = or ; button on the
steering wheel to select the Sett. menu.
X Press the : or 9
button to select the
Lights submenu.
X Press a to confirm.
X Press the :
or 9

button to select the
Interior Lighting Delay function.
You will see the selected setting: Enabled
or Disabled.
X Press the a button to save the setting.
Vehicle Activating/deactivating the automatic
door locking mechanism
X
Press the = or ; button on the
steering wheel to select the Sett menu.
X Press the :
or 9
button to select the
Vehicle submenu.
X Press a to confirm.
X Press the :
or 9

button to select the
Automatic Door Lock function.
You will see the selected setting: Enabled
or Disabled.
X Press the a button to save the setting.
If you select the Automatic Door Lock
function, the
vehicle

is centrally locked above
a speed of around 9 mph (15 km/h).
i For further information on the automatic
locking feature, see ( Y page 74).198
Menus and submenus
On-board computer and displays
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This display message will only appear if all LEDs have failed.
Display messages Possible causes/consequences and
M Solutionsb
Check Left
Cornering Light
 or 
Check Right
Cornering Light The left or right-hand cornering light is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 104).
or
X Visit a qualified specialist workshop. b
Check Left Low
Beam or Check
Right Low Beam The left or right-hand low-beam headlamp is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 104).
or
X Visit a qualified specialist workshop. b
Check Rear Left
Turn Signal or 
Check Rear Right
Turn Signal The rear left-hand or rear right-hand turn signal is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 104).
or
X Visit a qualified specialist workshop. b
Check Front Left
Turn Signal or 
Check Front Right
Turn Signal The front left-hand or front right-hand turn signal is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 104).
or
X Visit a qualified specialist workshop. b
Check Left Mirror
Turn Signal or 
Check
Right
Mirror
Turn Signal The turn signal in the left-hand or right-hand exterior mirror is
defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 104).
or
X Visit a qualified specialist workshop. b
Check Center
Brake
Lamp The high-mounted brake lamp is faulty.
X
Check whether you are permitted to replace the bulb yourself
(Y page 104).
or
X Visit a qualified specialist workshop. Display messages
209On-board computer and displays Z
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Checking and adding other service
products
Checking coolant level G
WARNING
The engine cooling system is pressurized,
particularly when the engine is warm. When
opening the cap,
you could be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape.
! The coolant may only be checked and
corrected when the engine is cool (coolant
temperature below 104 ‡ (40 †).
Checking the coolant when the coolant
temperature is above 104 ‡ (40 †) may
result in damage to the engine or to the
engine cooling system. Example
X
Park the vehicle on a level surface.
Only check the coolant level when the
vehicle is on

a level surface and the engine
has cooled down.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
104 ‡ (40 †).
X Turn the SmartKey to position
0 (

Y page 135) in the ignition lock. X
Slowly turn cap : half a turn counter-
clockwise to allow excess pressure to
escape.
X Turn cap : further counter-clockwise
and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
X If necessary, add coolant that has been
tested and approved by Mercedes-Benz.
X Replace cap : and turn

it clockwise as far
as it will go.
For further information on coolant, see
(Y page 333).
Adding washer fluid to the windshield
washer system/headlamp cleaning
system G
WARNING
Windshield washer concentrate is highly
flammable. If it comes into contact with hot
engine components or the exhaust system it
could ignite. There is a risk of fire and injury.
Make sure that no windshield washer
concentrate is spilled next to the filler neck. Example
X
To open: pull cap : upwards by the tab.
X Add the premixed washer fluid.
X To close:
press cap :
onto the filler neck
until it engages. Engine compartment
269
Maintenance and care Z
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