2012 MERCEDES-BENZ B-CLASS engine

particularly if the vehicle is moving, exhaust
fumes could enter the passenger
compartment. There is a risk of poisoning.
Turn off the engine before opening the
tailgate. Never drive with the tailgate open.
G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
! The tailgate swings upwards and to the
rear when opened. Therefore, make sure
that there is
sufficient clearance above and
behind the tailgate.
i The opening dimensions of the tailgate
can be found in the "Vehicle data" section
(Y page 335).
You should preferably place luggage or loads
in the cargo compartment. Observe the
loading guidelines ( Y page 236).
Do not leave the SmartKey in the cargo
compartment. You could otherwise lock
yourself out.
The tailgate can be:
R opened and closed manually from outside
R unlocked from inside with the mechanical
key Opening/closing from outside
Opening X
Press the % button on the SmartKey. X
Pull handle :.
X Raise the tailgate.
Closing X
Pull the tailgate down using handle :.
X Allow the tailgate to drop into the lock.
X If necessary, lock the vehicle with the
& button on the SmartKey. Tailgate emergency release
If the tailgate can no longer be opened from
outside the vehicle, use the emergency
release on the inside of the tailgate.
! The tailgate swings upwards and to the
rear when opened. Therefore, make sure
that there is

sufficient clearance above and
behind the tailgate.
i The opening dimensions of the tailgate
can be found in the "Vehicle data" section
(Y page 335). 76
Cargo compartment
Opening and closing
ProCarManuals.com

:
Front left
; Front right
= Rear right
? Rear left
i When the override feature for the side
windows is activated (
Y page 58), the side
windows
cannot be operated from the rear.
X Turn the SmartKey to position 1 or 2
in the
ignition lock.
X To open: press the corresponding switch.
X To open fully: press the corresponding
switch beyond the point of resistance.
Automatic closing is started.
X To close: pull the corresponding switch.
X To close fully: pull the corresponding
switch beyond the pressure point.
Automatic closing is started.
X To interrupt the automatic opening/
closing: press/pull the corresponding
switch again.
i If you press the switch beyond the point
of resistance, an automatic opening/
closing process is started in the
corresponding direction. You can stop
automatic operation by operating the
switch again.
i You can continue to operate the side
windows after you

switch off the engine or
remove the SmartKey. This function is
available for up to five minutes or until the
driver's or front-passenger door is opened. Convenience opening
You can ventilate

the vehicle before you start
driving. To do this, the SmartKey is used to
carry out the following functions
simultaneously:
R unlock the vehicle
R open the side windows
R open the panorama roof with power tilt/
sliding panel and the roller sunblinds
i The convenience opening feature can
only be operated using the SmartKey. The
SmartKey must be close to the driver's
door handle.
X Point the tip of the SmartKey at the driver's
door handle.
X Press and hold the % button until the
side windows and the panorama roof with
power tilt/sliding panel are in the desired
position.
If the roller

sunblinds of the panorama roof
with power tilt/sliding panel are closed, the
roller sunblinds are opened first.
X Press and hold the % button again
until
the panorama roof with power tilt/sliding
panel is in the desired position.
X To interrupt convenience opening:
release the % button. Convenience closing feature
G
WARNING
When the convenience closing feature is
operating, parts of the body could become
trapped in the

closing area of the side window
and the sliding sunroof. There is a risk of
injury.
Observe the complete closing procedure
when the convenience closing feature is
operating. Make sure that no body parts are
in close proximity during the closing
procedure. 78
Side windows
Opening and closing
ProCarManuals.com

Operating the sliding sunroof
Overhead control panel
:
To raise
; To open
= To close/lower
X Turn the SmartKey to position 1 or
2 in the
ignition lock.
X Make sure that the roller sunblinds are
open.
X Press or pull the 3 switch in the
corresponding direction.
i If you press the 3 switch beyond the
point of resistance,

an automatic opening/
closing process is started in the
corresponding direction. You can stop
automatic operation by operating the
switch again.
The automatic raising feature is available
only when the sliding sunroof is closed.
i You can continue to operate the sliding
sunroof after switching off the engine or
removing the SmartKey from the ignition
lock. This function remains active for five
minutes or until you open a front door. Operating the roller sunblinds for the
sliding sunroof
Important safety notes G
WARNING
When opening or closing the roller sunblind,
parts of the body could be trapped between the roller sunblind and the frame or sliding
sunroof. There is a risk of injury.
When opening or closing make sure that no
parts of
the

body are in the sweep of the roller
sunblind.
If somebody becomes trapped:
R release the switch immediately, or
R during automatic operation, push the
switch briefly in any direction
The opening or closing procedure will be
stopped.
The roller sunblinds shield the vehicle interior
from sunlight. The two roller sunblinds can
only be opened and closed together when the
sliding sunroof is closed.
Roller sunblind reversing feature The roller sunblinds are equipped with an
automatic reversing feature. If a solid object
blocks or
restricts

a roller sunblind during the
closing process, the roller sunblind opens
again automatically. However, the automatic
reversing feature is only an aid and does not
relieve you of the responsibility of paying
attention when closing the roller sunblinds. G
WARNING
The reversing feature does not react:
R to soft, light and thin objects, e.g. small
fingers
R when closing the roller sunblind again
manually immediately after automatic
reversing
This means that the reversing feature cannot
prevent someone being trapped in these
situations. There is a risk of injury.
When closing make sure that no parts of the
body are in the sweep of the roller sunblind.
If somebody becomes trapped:
R release the switch immediately, or
R during automatic operation, push the
switch briefly in any direction
The closing process is stopped. Panorama roof with power tilt/sliding panel
81
Opening and closing Z
ProCarManuals.com

Seats
Important safety notes
G
WARNING
Children could become trapped if they adjust
the seats, particularly when unattended.
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. 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
If you adjust the seat height carelessly, you or
other vehicle occupants

could be trapped and
thereby injured. Children in particular could
accidentally press the electrical seat
adjustment buttons and become trapped.
There is a risk of injury.
While moving the seats, make sure that your
hands or other body parts do not get under
the lever assembly of the seat adjustment
system. G
WARNING
When you adjust a seat, you or other vehicle
occupants could become

trapped, e.g. on the
seat guide rail. There is a risk of injury.
Make sure when adjusting a seat that no one
has any body parts in the sweep of the seat. G
WARNING
The seat belt does not offer the intended level
of protection if the backrest is not in the
upright position. When

braking or in the event of an accident, you could slide underneath the
seat belt and sustain abdomen or neck
injuries, for
example.

This poses an increased
risk of injury or even fatal injury.
Adjust the seat properly before beginning
your journey. Always make sure that the seat
is in the upright position. 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. G
WARNING
According to accident statistics, children are
safer when properly restrained on the rear
seats than on

the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seat whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriately sized
child restraint system or booster seat
recommended for the size and weight of the
child. For additional information, see the
"Children in the vehicle" section.
A child's risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.
! To avoid damage to the seats and the seat
heating, observe the following information:
R keep liquids from spilling on the seats. If
liquid is spilled on the seats, dry them as
soon as possible.
R if the seat covers are damp or wet, do not
switch on the seat heating. The seat Seats
87
Seats, steering wheel and mirrors Z
ProCarManuals.com

i
You can store the seat settings using the
memory function ( Y page 95).Adjusting the head restraints
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
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.
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 fore/aft position of the
head restraint With this function you can adjust the distance
between the head restraint and the back of
the seat occupant's head.
X
To adjust forwards: pull the
head restraint
forwards in the direction of the arrow until
it engages.
There are several notches.
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
position.
Adjusting the height of the head
restraints electrically X
To adjust the head restraint height: slide
the switch for head restraint adjustment
( Y

page 88) up or down in the direction of
the arrow. Seats
89
Seats, steering wheel and mirrors Z
ProCarManuals.com

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
ProCarManuals.com

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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Rear fog lamp
The rear fog lamp improves visibility of your
vehicle for the traffic behind in the event of
thick fog. Please take note of the country-
specific regulations for the use of rear fog
lamps.
X
To switch on the rear 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 R button.
The yellow R indicator lamp in the
instrument cluster lights up.
X To switch off the rear fog lamp: press the
R
button.
The yellow R indicator lamp in the
instrument cluster goes out.
Parking lamps
! If the battery has been excessively
discharged, the parking lamps or standing
lamps are automatically switched off to
enable the next engine start. Always park
your vehicle safely and sufficiently lit
according to legal standards. Avoid the
continuous use of the T parking lamps
for several hours.

If possible, switch on the
X right or the W left standing lamp.
X To switch on: turn the light switch to
T.
The green T indicator lamp in the
instrument cluster lights up.
Standing lamps
Switching on the

standing lamps ensures the
corresponding side of the vehicle is
illuminated.
X To switch on the standing lamps: the
SmartKey is not in the ignition lock or it is
in position 0.
X Turn the light switch to W (left-hand side
of the vehicle) or
X (right-hand side of
the vehicle). Combination switch
Turn signal :
High-beam headlamps
; Turn signal, right
= High-beam flasher
? Turn signal, left
X To indicate briefly: press the
combination
switch briefly to the pressure point in the
direction of arrow

; or ?.
The corresponding turn signal flashes three
times.
X To indicate: press the combination
switch
beyond the pressure point in the direction
of arrow ; or ?.
High-beam headlamps X
To switch on the high-beam headlamps:
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 combination switch beyond the
pressure point in the direction of
arrow :.
In the à position, the high-beam
headlamps are only switched on when it is
dark and the engine is running. 100
Exterior lighting
Lights and windshield wipers
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