warning light MERCEDES-BENZ B-CLASS 2012 Owner's Guide

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 installing the rear seat
head restraints G
WARNING
If head restraints are not installed and
adjusted correctly, they cannot provide
protection as intended.

There is an increased
risk of injury in the head and neck area, e.g.
in the event of an accident or when braking.
Always drive with the head restraints
installed. Before driving off, make sure for
every vehicle occupant that the center of the
head restraint supports the back of the head
at about eye level.
The rear head restraints on the outer seats
can be removed and re-installed. X
Fold the seat backrest slightly forwards in
order to remove the head restraint
(Y page 240).
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 re-install: 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 contour90
Seats
Seats, steering wheel and mirrors
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Switching the seat heating on/off
Activating/deactivating G
WARNING
Repeatedly switching on the seat heating can
cause the seat cushion and backrest pads to
become very hot. The health of persons with
limited temperature sensitivity or a limited
ability to react to excessively high
temperatures may be affected or they may
even suffer burn-like injuries. There is a risk
of injury.
Therefore, do not switch the seat heating on
repeatedly. The three red indicator lamps in the button
indicate the heating level you have selected.
The system automatically switches down
from level 3 to level 2 after approximately
eight minutes.
The system automatically switches down
from level
2
to level 1 after approximately ten
minutes.
The system automatically switches off
approximately 20 minutes after it is set to
level 1.
X Make sure that the SmartKey is in position
1 or 2 in the ignition lock.
X To switch on: press button : repeatedly
until the desired heating level is set.
X To switch off: press button : repeatedly
until all the indicator lamps go out.
i If the battery voltage is too low, the seat
heating may switch off. Problems with the seat heating The seat heating has switched off
prematurely or cannot be switched on. The
vehicle's electrical system voltage is too low
because too many electrical consumers are
switched on.
X
Switch off electrical consumers that you do
not need, such as the rear window
defroster or interior lighting. Steering wheel
Important safety notes
G
WARNING
You could lose control of your vehicle if you
do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint,
steering wheel and mirror and fasten your
seat belt before starting the engine. G
WARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you

and lock the vehicle. Never
leave children unsupervised in the vehicle. Adjusting the steering wheel
G
WARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident.
Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion. Steering wheel
91
Seats, steering wheel and mirrors Z
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:
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-glare mode: flick anti-glare lever :
forwards or back. Exterior mirrors
Adjusting the exterior mirrors G
WARNING
The exterior mirror on the front-passenger
side reduces the size of the image. Visible
objects are actually closer than they appear.
This means that you could misjudge the
distance from road users traveling behind,
e.g. when changing
lane. There is a risk of an
accident.
For this reason, always make sure of the
actual distance from the road users traveling
behind by glancing over your shoulder. X
Make sure that the SmartKey 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
exterior 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.
The exterior
mirrors

are automatically heated
after starting the vehicle if the rear window 92
Mirrors
Seats, steering wheel and mirrors
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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note
that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 24).Exterior lighting
General notes
For reasons of safety, Mercedes-Benz
recommends that you drive with the lights
switched on even

during the daytime. In some
countries, operation of the headlamps varies
due to legal requirements and self-imposed
obligations. Driving abroad
Conversion to symmetrical low beam Switch the headlamps to symmetrical low
beam in countries in which traffic drives on
the opposite
side

of the road from the country
where the vehicle is registered. This prevents
glare to oncoming traffic. When using
symmetrical lights, the edge of the road is not
lit as widely and as far ahead as normal.
Have the headlamps converted at a qualified
specialist workshop as close to the border as
possible before driving in these countries.
Conversion to asymmetrical low beam
after returning Have the headlamps converted back to
asymmetrical low-beam headlamps at a
qualified specialist workshop as soon as
possible after crossing the border again. Setting the exterior lighting
Setting options Exterior lighting can be set using:
R
the light switch
R the combination switch ( Y page 100)
R the on-board computer (Y page 197)
Light switch Operation
1W
Left-hand standing lamps
2X Right-hand standing lamps
3T Parking lamps, license plate and
instrument cluster lighting
4Ã Automatic headlamp mode,
controlled by the light sensor
5L Low-beam/high-beam headlamps
BR Rear fog lamp
CN Fog lamp (only vehicles with front fog
lamps)
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 parking/
standing lamps) switches off automatically if
you:
R remove the
SmartKey

from the ignition lock
R open the driver's door with the SmartKey
in position 0.98
Exterior lighting
Lights and windshield wipers
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Automatic headlamp mode
G
WARNING
When the light switch is set to Ã,
the low-
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 favored light switch setting. The
light setting is automatically selected
according to the brightness of the ambient
light (exception: poor visibility due to weather
conditions such as fog, snow or spray):
R SmartKey in position 1 in the ignition lock:
the parking lamps are switched on or off
automatically depending on the brightness
of the ambient light.
R With the engine running: if you have
activated the daytime running lamps
function via the on-board computer, the
daytime running lamps or the low-beam
headlamps and parking lamps 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 running lamps improve the
visibility of your vehicle during the day. The
daytime running lamps

function is required by
law in Canada.
When the engine is running and the vehicle is
stationary: if you move the selector lever from
a drive position to P, the daytime running
lamps/low-beam headlamps go out after
three minutes.
When the engine is running, the vehicle is
stationary and in high ambient light: if you
turn the light switch to T, you turn on the
daytime running lamps and parking lamps. If the engine is running and you turn the light
switch to L, the manual settings take
precedence over the daytime running lamps.
Low-beam headlamps
Even if the light sensor does not detect that
it is dark, the parking lamps and low-beam
headlamps switch on when the ignition is
switched
on and

the light switch is set to the
L position. This is a particularly useful
function in the event of rain and fog.
X To switch on the low-beam headlamps:
turn the SmartKey in the ignition lock to
position 2 or start the engine.
X Turn the light switch to L.
The green L indicator lamp in the
instrument cluster lights up.
Front fog lamps
In conditions where visibility is poor due to
fog, snow or rain, the fog lamps improve
visibility as well as making it easier for other
road users to see you. They can be operated
together with the parking lamps or together
with the parking lamps and low-beam
headlamps.
X To switch on the front fog lamps: turn
the SmartKey in

the ignition lock to position
2 or start the engine.
X Turn the light switch to L or Ã.
X Press the N button.
The green N indicator lamp in the
instrument cluster lights up.
X To switch off the front fog lamps: press
the N button.
The green N indicator lamp in the
instrument cluster goes out.
Only vehicles with front fog lamps are
equipped with the "fog lamp" function;
information on the fog lamp function for
vehicles with Intelligent Light System
(Y page 102). Exterior lighting
99Lights and windshield wipers Z
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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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?
| 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
Lights and windshield wipers
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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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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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