belt MERCEDES-BENZ B-CLASS 2012 Owner's Manual

If the front-passenger seat of your vehicle
does not
have
an air bag deactivation system,
this is indicated by a special sticker. The
sticker is affixed to the side of the dashboard
on the front-passenger side. The sticker is
visible when you open the front-passenger
door.
Vehicles without an air bag deactivation
system on the front-passenger seat: if you
turn the SmartKey to position 2 in the ignition
lock, the 45 indicator lamp lights up
briefly but has no function. It does not
indicate that there is an air bag deactivation
system on the front-passenger seat. The sensor system for the air bag deactivation
system detects
whether

a special Mercedes-
Benz child seat with a transponder for the air
bag deactivation system has been installed.
In this case, 45 indicator lamp :
lights up. The front-passenger front air bag is
deactivated: i
If the front-passenger front air bag is
disabled by the air bag deactivation
system, the following remain enabled on
the front-passenger side:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Device
LATCH-type (ISOFIX) child

seat anchors
in the rear G
WARNING
Children that are too large for a child restraint
must travel in seats using normal seat belts.
Position the shoulder belt across the chest
and shoulder, not the face or neck.
A booster seat may be necessary to achieve
proper seat belt positioning for children over
41 lbs (18 kg

) until they reach a height where
a normal shoulder/lap belt fit properly
without a booster.
Install the child seat according to
manufacturer's instructions.
The child seat must be firmly attached to both
anchors.
An incorrectly installed child restraint system
could come loose during an accident and
seriously or even fatally injure the child.
Damaged or impact damaged child seats or
child seat mountings must be replaced.
! When installing the LATCH-type (ISOFIX)
child restraint system, make sure that the
seat belt for the center seat does not get
trapped. Otherwise, the seat belt could be
damaged. 54
Children in the vehicle
Safety
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X
Install the LATCH-type (ISOFIX) child
restraint system. Comply with the
manufacturer's instructions when
installing the LATCH-type (ISOFIX) child
restraint system.
LATCH-type (ISOFIX) is a standardized
securing system for specially designed child
restraint systems on
the rear seats. Securing
rings : for two LATCH-type (ISOFIX) child
restraint systems are installed on the left and
right of the rear seats.
Secure child restraint systems without a
LATCH-type (ISOFIX) child seat securing
system using the seat belts in the vehicle.
When installing child restraint systems, you
must observe the manufacturer's installation
instructions.
Top Tether Important safety notes
G
WARNING
If the red display is visible when the rear seat
backrest is upright, it means the rear seat
backrest is not engaged correctly.
Always engage the rear seat backrests in an
upright position if

there are passengers in the
rear compartment. Engage the rear seat
backrests in an upright position after you have
installed the Top Tether belt or if the extended
cargo compartment is not being used. Push
and pull the rear seat backrests to check
whether they are engaged correctly. The rear
seat backrest may fold down if it is not
engaged correctly. The child restraint system is then no longer supported correctly or held
in position and can no longer perform its
intended function. This can cause serious or
even fatal injuries.
Top Tether provides an additional connection
between a child restraint system, secured
with a
LATCH-type

(ISOFIX) child seat mount,
and the rear seat. This helps reduce the risk
of injury even further.
The Top Tether anchorage points are installed
on the rear side of the rear seat backrests.
X Move head restraint : upwards.
X Release rear seat backrest = and fold it
forwards ( Y page 240).
X Route Top Tether belt B under head
restraint : between the

two head restraint
bars.
X Hook Top Tether hook A of
Top
Tether belt
B into Top Tether anchorage ?. Children in the vehicle
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Safety Z
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Make sure that:
R
Top Tether hook A is hooked into Top
Tether anchorage ? as shown.
R Top Tether belt B is not twisted.
R Top Tether
belt B
is routed between rear
seat backrest = and cargo
compartment cover ; if cargo
compartment cover ; is installed.
X Swing back rear seat backrest = until it
engages.
The red lock verification indicator is no
longer visible.
X Move head restraint : back down again
slightly if necessary (
Y page 90). Make
sure that you do not interfere with the
correct routing of Top Tether belt B

.
X Install the LATCH-type (ISOFIX) child
restraint system with Top Tether. Comply
with the manufacturer's installation
instructions when
doing

so. Make sure that
Top Tether belt B is tight. 56
Children in the vehicle
Safety
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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).Correct driver's seat position
Observe the safety guidelines on seat
adjustment (
Y page 87).
X Make sure that seat = is adjusted
properly.
Manual seat adjustment ( Y page 88)
Electrical seat adjustment ( Y page 88)
When adjusting the seat, make sure that:
R you are as far away from the driver's air
bag as possible.
R you are sitting in a normal upright
position.
R you can fasten the seat belt properly. R
you have moved the backrest to an
almost vertical position.
R you have set the seat cushion angle so
that your thighs are gently supported.
R you can depress the pedals properly.
X Check whether the head restraint is
adjusted properly ( Y page 89).
When doing so, make sure that you have
adjusted

the head restraint so that the back
of your head is supported at eye level by
the center of the head restraint.
Observe the safety guidelines on steering
wheel adjustment ( Y page 91).
X Make sure that steering wheel : is
adjusted properly.
Adjusting the steering wheel
(Y page 91)
When adjusting the steering wheel, make
sure that:
R you can hold

the steering wheel with your
arms slightly bent.
R you can move your legs freely.
R you can see all the displays in the
instrument cluster clearly.
Observe the safety guidelines for seat belts
(Y page 45).
X Check whether you have fastened seat
belt ; properly ( Y page 47).
The seat belt should:
R fit snugly across your body
R be routed across the middle of your
shoulder
R be routed in your pelvic area across the
hip joints
X Before starting off, adjust the rear-view
mirror and the exterior mirrors
(

Y page 92) in such a way that you have
a good view of road and traffic conditions.
X Vehicles with a memory function: save
the seat and exterior mirror settings
(Y page 95). 86
Correct driver's seat position
Seats, steering wheel and mirrors
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
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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
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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
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The stop/start function is automatically
activated each
time
you start the engine with
the SmartKey.
If the ECO start/stop function has been
manually deactivated ( Y page 138) or a
malfunction has caused the system to be
deactivated, the ¤ symbol is not
displayed.
Automatic engine switch-off General notes
The ECO start/stop function is operational
and the ¤ symbol is displayed in the
multifunction display, if:
R
the indicator lamp in the ECO button is lit
green.
R the outside temperature is within the
comfort range.
R the engine is at normal operating
temperature.
R the set temperature

for the vehicle interior
has been reached.
R the battery is sufficiently charged.
R the system detects that the windshield is
not fogged up when the air-conditioning
system is switched on.
R the hood is closed.
R the driver's door is closed and the driver's
seat belt is fastened.
If conditions for automatic engine switch-off
have not been fulfilled, the ¤ symbol will
not be shown.
i All of the vehicle's systems remain active
when the engine has been stopped
automatically.
i The engine can be switched off
automatically a maximum of four times
(first stop and three subsequent stops) in
succession. Automatic engine switch-off is
possible again once the ECO symbol
appears in the multifunction display. Vehicles with automatic transmission
If the vehicle is braked to a standstill in
D or
N, the ECO start/stop function switches off
the engine automatically.
i The HOLD function

can be activated if the
engine has been switched off
automatically. It is then not necessary to
continue applying the brakes during the
automatic stop phase. When you depress
the accelerator pedal, the engine starts
automatically and the braking effect of the
HOLD function is deactivated.
Automatic engine start General notes
The engine starts automatically if:
R
you switch off

the ECO start/stop function
by pressing the ECO button.
R you engage reverse gear R.
R the vehicle starts to roll.
R the brake system requires this.
R the temperature in the vehicle interior
deviates from the set range.
R the system detects moisture on the
windshield when the air-conditioning
system is switched on.
R the condition of charge of the battery is too
low.
R the driver's seat belt is removed or the
driver's door is opened.
Vehicles with automatic transmission
The engine is started automatically if you:
R release the brake pedal when HOLD is not
activated and the transmission is in
position D or N.
R depress the accelerator pedal.
R move the transmission out of position P.
i Shifting the transmission to position P
does not start the engine.
i If you shift the transmission from R to D,
the ECO start/stop function is available Driving
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Driving and parking Z
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engine is switched off. The sounds that can
be heard
while
this is occurring are normal.
Applying/releasing manually Applying
X
Push handle :.
When the electric parking brake is
engaged, the !

red indicator lamp lights
up in the instrument cluster.
i The electric parking brake can also be
applied when the SmartKey is removed.
Releasing
X Pull handle :.
The red ! indicator lamp in the
instrument cluster goes out.
i You can only release the electric parking
brake when the key is in position 1 or 2 in
the ignition lock.
Applying automatically The electric parking brake is applied
automatically:
R
if DISTRONIC PLUS brings the vehicle to a
standstill or
R if the HOLD

function is keeping the vehicle
stationary
In addition, at least one of the following
conditions must be fulfilled:
R the engine is switched off.
R the driver's door is open and the seat belt
is not fastened.
R there is a system malfunction.
R the power supply is insufficient.
R the vehicle is stationary for a lengthy
period.
The red ! indicator lamp in the instrument
cluster lights up.
i The electric parking brake is not
automatically engaged if the engine is
switched off by the ECO start/stop
function. Releasing automatically Your vehicle's electric parking brake is
automatically released if all of the following
conditions are met:
R
the engine is running.
R the transmission is in position D or R.
R the seat belt has been fastened.
R you depress the accelerator pedal.
If the transmission

is in position R, the tailgate
must be closed.
If your seat belt is not fastened, the following
conditions must be fulfilled to automatically
release the electric parking brake:
R the driver's door is closed.
R you have shifted out of transmission
position P or you have previously driven
faster than 2 mph (3 km/h).
Emergency braking The vehicle can also be braked during an
emergency by using the electric parking
brake.
X
While driving, push handle : of the
electric
parking brake ( Y page 150).
i The vehicle is braked for as long as
handle : of the electric parking brake is
pressed. The longer electric parking brake
handle : is depressed, the greater the
braking force.
During braking:
R a warning tone sounds
R the Release Park. Brake message
appears
R the red ! indicator lamp in the
instrument cluster flashes
When the vehicle has been braked to a
standstill, the electric parking brake is
engaged. Parking
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Driving and parking Z
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R
the transmission must be in position D.
R the driver's door
must be closed when you
shift from P to D or your seat belt must be
fastened.
R the front-passenger door and rear doors
must be closed.
R the vehicle must not skid.
Activating
To activate while driving: when driving at
speeds below 14 mph (20 km/h), you can
only activate DISTRONIC PLUS if the vehicle
in front has been detected and is shown in the
multifunction display. If the vehicle in front is
no longer detected and displayed,
DISTRONIC PLUS switches off and a tone
sounds.
X Briefly pull the cruise control level towards
you ?, or press it up : or down ;.
DISTRONIC PLUS is selected.
X Press the cruise control lever repeatedly
up : or down ; until the desired speed
is set.
X Remove your foot from the accelerator
pedal.
Your vehicle adapts

its speed to that of the
vehicle in front, but only up to the desired
stored speed.
i If you do

not fully release the accelerator
pedal, the DISTRONIC PLUS Passive
message appears in the multifunction
display. The set distance to a slower-
moving vehicle in front will then not be
maintained. You will be driving at the speed
you determine by the position of the
accelerator pedal.
To activate when driving towards a
stationary vehicle: if the vehicle in front is
stationary, you can only activate DISTRONIC
PLUS if your vehicle is also stationary.
X Briefly pull the cruise control level towards
you ?, or press it up : or down ;.
DISTRONIC PLUS is selected.
i DISTRONIC PLUS
can

only be activated at
under 14 mph (20 km/h) if a vehicle in front has been detected. It is therefore helpful to
have the
DISTRONIC

PLUS distance display
activated in the multifunction display
(Y page 194).
X Press the cruise control lever repeatedly
up : or down ; until the desired speed
is set.
i You can
use

the cruise control lever to set
the stored speed and the control on the
cruise control lever to set the specified
minimum distance (Y page 165). DISTRONIC PLUS displays in the speedometer
When DISTRONIC PLUS is activated, one or
two segments
;

in the set speed range light
up.
i For design reasons, the speed displayed
in the speedometer may differ slightly from
the speed set for DISTRONIC PLUS.
If DISTRONIC PLUS detects a vehicle in front,
segments ; between speed of the vehicle in
front : and stored speed = light up.162
Driving systems
Driving and parking
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