warning MERCEDES-BENZ B-CLASS 2012 Workshop Manual

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

You can reach the emergency release via the
cargo compartment. Fold the rear backrests
forward (
Y page 240).
X Take the mechanical key out of the
SmartKey (Y page 69). X
Insert mechanical key ; into the opening
in paneling :.
X Turn mechanical key ; 90° clockwise.
X Push mechanical key ; in the
direction of
the arrow and open the tailgate. Side windows
Important safety notes
G
WARNING
While opening the side windows, body parts
in the closing area could become trapped.
There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure. If
somebody becomes trapped, release the
switch or press the switch to open the side
window again. G
WARNING
If children operate the side windows they
could become trapped,

particularly if they are
left unsupervised. There is a risk of injury.
Activate the override feature for the rear side
windows. When leaving the vehicle, always
take the SmartKey with you and lock the
vehicle. Never leave children unsupervised in
the vehicle. Side window reversing feature
The side windows are equipped with an
automatic reversing feature. If a solid object
blocks or restricts a side window during the
closing process, the

side window 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 a side window. G
WARNING
The reversing feature does not react:
R to soft, light and thin objects, e.g. small
fingers
R over the last

4 mm of the closing movement
R during resetting
R when closing the side window 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.
Make sure that no body parts are in close
proximity during the closing procedure. If
someone becomes trapped, press the switch
to open the side window again. Opening and closing the side
windows
The switches for

all side windows are located
on the driver's door. There is also a switch on
each door for the corresponding side window.
The switches on the driver's door take
precedence. Side windows
77
Opening and closing Z
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

When you lock the vehicle, you can
simultaneously:
R
close the side windows
R close the panorama roof with power tilt/
sliding panel
On vehicles with
a panorama roof with power
tilt/sliding panel, you can then close the
roller sunblinds.
i 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 fully closed.
X Make sure that all the side windows and the
panorama roof with power tilt/sliding
panel are closed.
On vehicles with a panorama roof with power
tilt/sliding panel:
X Press and hold the & button again
until
the roller sunblinds of the panorama roof
with power tilt/sliding panel close.
X To interrupt convenience closing:
release the & button.Resetting the side windows
You must reset each side window if:
R the side window opens again slightly after
being closed fully.
R the side window can no longer be fully
opened or closed.
X Close all the doors.
X Turn the SmartKey to position 1
or 2
in the
ignition lock.
X Pull the corresponding switch on the door
control panel until the side window is
completely closed ( Y page 77).
X Hold the switch for an additional second. If the side window opens again slightly:
X
Immediately
pull the corresponding switch
on the door control panel until the side
window is completely closed ( Y page 77).
X Hold the switch for an additional second.
X If the corresponding side window remains
closed after the button has been released,
the side window has been reset correctly.
If this is not the case, repeat the steps
above again. Problems with the side windows
G
WARNING
If you close a side window again immediately
after it has been blocked or reset, the side
window closes with increased or maximum
force. The reversing

feature is then not active.
Parts of the body could be trapped in the
closing area in the process. This poses an
increased risk of injury or even fatal injury.
Make sure that no parts of the body are in the
closing area. To stop the closing process,
release the switch or push the switch again to
reopen the side window.
Problem: a side window cannot be closed
because it is blocked by objects, e.g.
leaves in the window guide.
X Remove the objects.
X Close the side window.
Problem: a side window cannot be closed
and you cannot see the cause. If a side
window is obstructed during closing and
reopens again slightly:
X Immediately after the window blocks, pull
the corresponding switch again until the
side window has closed.
The side window is closed with increased
force. Side windows
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Opening and closing Z
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If a side window is obstructed again during
closing and reopens again slightly:
X
Immediately after the window blocks, pull
the corresponding switch again until the
side window has closed.
The side window
is closed without the anti-
entrapment feature. Panorama roof with power tilt/sliding
panel
Important safety notes
In the following section, the term "sliding
sunroof" refers to the panorama roof with
power tilt/sliding panel. G
WARNING
While opening and closing the sliding sunroof,
body parts in close proximity could become
trapped. There is a risk of injury.
Make sure that no body parts are in close
proximity during the opening and closing
procedures.
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. G
WARNING
If children operate the sliding sunroof they
could become trapped,

particularly if they are
left unsupervised. 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.
! Only open the sliding sunroof if it is free
of snow and ice. Otherwise, malfunctions
may occur.
Do not allow anything to protrude from the
sliding sunroof. Otherwise, the seals could
be damaged. !
The weather can

change abruptly. It could
start to rain or snow. Make sure that the
sliding sunroof is closed when you leave the
vehicle. The vehicle electronics can be
damaged if water enters the vehicle
interior.
i Resonance noises can occur in addition
to the usual airflow noises when the sliding
sunroof is open. They are caused by minor
pressure fluctuations in the vehicle interior.
Change the position of the sliding sunroof
or open a side window slightly to reduce or
eliminate these noises. Sliding sunroof reversing feature
The sliding sunroof is equipped with an
automatic reversing feature. If a solid object
blocks or restricts the sliding sunroof during
the closing process,

the sliding sunroof 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 sliding sunroof. G
WARNING
The reversing feature does not react:
R to soft, light and thin objects, e.g. small
fingers
R over the last

4 mm of the closing movement
R during resetting
R when closing the sliding sunroof 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.
Make sure that no body parts are in close
proximity during the closing procedure.
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. 80
Panorama roof with power tilt/sliding panel
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

Opening and closing
Overhead control panel
:
To open
; To open
= To close
X Turn the SmartKey to position 1 or
2 in the
ignition lock.
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.
Resetting the sliding sunroof and the
roller sunblinds If the sliding sunroof or the roller sunblinds
do not move smoothly, reset the sliding
sunroof and the roller sunblinds:
X
Turn the SmartKey to position 1 or 2
in the
ignition lock.
X Press the 3 switch to the point of
resistance in the

direction of arrow ; and
hold it until the sliding sunroof has opened
about 4 in (10 cm).
X Pull the 3 switch
repeatedly
to the point
of resistance in the direction of arrow =
until the sliding sunroof is fully closed.
X Keep the 3 switch pulled for an
additional second. X
Press the 3 switch to the point of
resistance in the

direction of arrow ; and
hold it until the roller sunblinds are open
about 4 in (10 cm).
X Pull the 3 switch
repeatedly
to the point
of resistance in the direction of arrow =
until the roller sunblinds are fully closed.
X Keep the 3 switch pulled for an
additional second.
X Make sure that the sliding sunroof
(Y page 81) and the roller sunblinds
(Y page
82)

can be fully opened and closed
again.
X If this is not the case, repeat the steps
above again. Problems with the sliding sunroof
G
WARNING
If you do not reset the sliding sunroof after a
malfunction or voltage supply interruption,
then the backing

up function will malfunction
or not work. The sliding sunroof closes with
increased or maximum force. Parts of the
body could be trapped in the closing area in
the process. This poses an increased risk of
injury or even fatal injury.
In such or similar situations always make sure
that no parts of the body are in the closing
area. Always reset the sliding sunroof after a
malfunction or voltage supply interruption.
! If the sliding sunroof still cannot be
opened or closed as a result of a
malfunction, contact a qualified specialist
workshop.
Problem: the sunroof cannot be closed
and you cannot see the cause. If the sliding
sunroof is obstructed during closing and
reopens again slightly:
X Immediately after it blocks, pull the 3
switch down again to the point of 82
Panorama roof with power tilt/sliding panel
Opening and closing
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
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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

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
ProCarManuals.com