ignition MERCEDES-BENZ B-CLASS 2012 Owners Manual

Important safety notes ..................
266
Opening ......................................... 266
Hydroplaning ..................................... 156I
Ignition lock see Key positions

Immobilizer .......................................... 64
Indicator lamps see Warning and indicator lamps
Instrument cluster
Overview .......................................... 29
Settings ......................................... 196
Warning and indicator lamps ...........30
Instrument cluster lighting .............. 186
Interior lighting ................................. 103
Automatic control .......................... 104
Delayed switch-off (on-board
computer) ...................................... 198
Emergency lighting ........................ 104
Manual control ............................... 104
Overview ........................................ 103
Reading lamp ................................. 103
Setting the brightness of the
ambient lighting (on-board
computer) ...................................... 197J
Jack Storage location ............................ 280
Using ............................................. 320
Jump starting (engine) ...................... 289K
Kickdown Driving tips .................................... 143
Manual drive program .................... 146
Knee bag .............................................. 44 L
Lamps see Warning and indicator lamps
Lane Keeping Assist
Activating/deactivating

.................195
Display message ............................ 215
Function/information .................... 183
Lane Tracking package .....................181
LATCH-type (ISOFIX) child seat
anchors ................................................ 54
License plate lamp Changing bulbs .............................. 111
License plate lamp (display
message) ............................................ 210
Light function, active Display message ............................ 211
Lighting
Light switch ..................................... 98
Lights
Activating/deactivating the
interior lighting delayed switch-off . 198
Automatic headlamp mode .............. 99
Cornering light function .................101
Display message ............................ 208
Driving abroad ................................. 98
Fog lamps ........................................ 99
Fog lamps (extended) ....................102
Hazard warning lamps ................... 101
High beam flasher .......................... 101
High-beam headlamps ...................100
Low-beam headlamps ...................... 99
Parking lamps ................................ 100
Rear fog lamp ................................ 100
Setting the brightness of the
ambient lighting (on-board
computer) ...................................... 197
Standing lamps .............................. 100
Switching Adaptive Highbeam
Assist on/off ................................. 197
Switching the daytime running
lamps on/off (on-board computer) 197
Switching the daytime running
lamps on/off (switch) ...................... 99
Switching the exterior lighting
delayed switch-off on/off (on-
board computer) ............................ 198 Index
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(vehicles without the EASY-
VARIO-PLUS system)
.....................240
Folding the backrest (rear
compartment) forwards/back
(vehicles with the EASY-VARIO-
PLUS system) ................................ 241
Seat belts
Adjusting the height ......................... 48
Belt force limiters ............................ 49
center rear-compartment seat
.........48
Cleaning ......................................... 277
Correct usage .................................. 46
Emergency Tensioning Devices ........ 49
Fastening ......................................... 47
Important safety guidelines .............45
Releasing ......................................... 48
Safety guidelines ............................. 40
Warning lamp ................................. 224
Warning lamp (function) ................... 49
Seats
Adjusting (electrically) .....................88
Adjusting (manually) ........................ 88
Adjusting the 4-way lumbar
support ............................................ 90
Adjusting the head restraint ............ 89
Cleaning the cover ......................... 276
Correct driver's seat position ........... 86
Important safety notes .................... 87
Seat heating problem ...................... 91
Storing settings (memory function) .. 95
Switching seat heating on/off ......... 91
Sensors (cleaning instructions) .......275
Service menu (on-board computer) . 196
Service products Brake fluid ..................................... 332
Coolant (engine) ............................ 333
Engine oil ....................................... 332
Fuel ................................................ 330
Important safety notes .................. 329
Refrigerant (air-conditioning
system) .......................................... 334
Washer fluid ................................... 334
Service work
see ASSYST PLUS
Settings
Factory (on-board computer) ......... 199
On-board computer ....................... 196
Setting the air distribution ...............126Setting the airflow
............................ 126
Side impact air bag ............................. 44
Side marker lamp (display
message) ............................................ 211
Side windows Cleaning ......................................... 274
Convenience closing feature ............ 78
Convenience opening feature
..........78
Important safety information ........... 77
Opening/closing .............................. 77
Problem (malfunction) .....................79
Resetting ......................................... 79
Sliding sunroof
see Panorama roof with power
tilt/sliding panel
SmartKey
Changing the battery ....................... 70
Changing the programming ............. 69
Checking the battery ....................... 70
Convenience closing feature ............ 78
Convenience opening feature .......... 78
Display message ............................ 223
Door central locking/unlocking ....... 68
Important safety notes .................... 68
Loss ................................................. 72
Mechanical key ................................ 69
Positions (ignition lock) ................. 135
Problem (malfunction) .....................72
Starting the engine ........................ 135
SmartKey positions (ignition lock) ..135
Snow chains ...................................... 301
Sockets Center console .............................. 251
Luggage compartment ................... 251
Points to observe before use ......... 250
Rear compartment ......................... 251
Specialist workshop ............................ 24
Speed, controlling see Cruise control
Speedometer
Activating/deactivating the
additional speedometer .................196
Digital ............................................ 190
In the Instrument cluster ................. 29
Segments ...................................... 187
Selecting the unit of measurement 196
see Instrument cluster Index
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Operating safety
Important safety notes
G
WARNING
If you do not have the prescribed service/
maintenance work or any required repairs
carried out, this
can result in malfunctions or
system failures. There is a risk of an accident.
Always have the prescribed service/
maintenance work as well as any required
repairs carried out at a qualified specialist
workshop. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or

not at all. This could affect,
for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving. G
WARNING
Modifications to electronic components, their
software as well as wiring can impair their
function and/or the function of other
networked components. In particular,
systems relevant to safety could also be
affected. As a result, these may no longer
function as intended and/or jeopardize the
operating safety of the vehicle. There is an
increased risk of an accident and injury.
Never tamper with the wiring as well as
electronic components or

their software. You
should have all work to electrical and
electronic equipment carried out at a qualified
specialist workshop.
There is a risk of damage to the vehicle if:
R the vehicle becomes stuck, e.g. on a high
curb or an unpaved road
R you drive too fast over an obstacle, e.g. a
curb or a hole in the road
R a heavy object strikes the undercarriage or
parts of the chassis. In situations like this, the body, the
undercarriage, chassis parts, wheels or tires
could be
damaged

without the damage being
visible. Components damaged in this way can
unexpectedly fail or, in the case of an
accident, no longer withstand the strain they
are designed to.
If the underbody paneling is damaged,
combustible materials such as leaves, grass
or twigs can gather between the underbody
and the underbody paneling. If these
materials come in contact with hot parts of
the exhaust system for an extended period,
they can catch fire.
Have the vehicle checked and repaired
immediately at a qualified specialist
workshop. If on continuing your journey you
notice that driving safety is impaired, pull over
and stop the vehicle immediately, paying
attention to road and traffic conditions. In
such cases, visit a qualified specialist
workshop. Declarations of conformity
Vehicle components which receive
and/or transmit radio waves USA: "The wireless devices of this vehicle
comply with Part 15 of the FCC Rules.
Operation is subject to the following two
conditions: 1) These devices may not cause
harmful interference, and 2) These devices
must accept any interference received,
including interference that may cause
undesired operation. Changes or
modifications not expressly approved by the
party responsible for compliance could void
the user’s authority to operate the
equipment."
Canada:
"The wireless

devices of this vehicle
comply with Industry Canada license-exempt
RSS standard(s). Operation is subject to the
following two conditions: (1) These devices
may not cause interference, and (2) These
devices must accept any interference, Introduction
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Dashboard
Function Page
:
Steering wheel paddle
shifters
144
;
Combination switch 100
=
Instrument cluster 29
?
Horn
A
DIRECT SELECT lever 140
B
PARKTRONIC warning
display
169
C
Overhead control panel 34
D
Climate control systems
118 Function Page
E
Ignition lock 135
F
Adjusting the steering
wheel
91
G
Cruise control lever 158
H
Electric parking brake 150
I
Light switch 98
J
Diagnostics connection 24
K
Opening the hood 26628
DashboardAt a glance
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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).Panic alarm
X
To activate: press ! button : for at
least one second.
An alarm sounds and the exterior lighting
flashes.
X To deactivate: press ! button :
again.
or
X Insert the SmartKey into the ignition lock. Occupant safety
Important safety notes
G
WARNING
Modifications to or work improperly
conducted on restraint system components
or their wiring, as well as tampering with interconnected electronic systems, can lead
to the
restraint
systems no longer functioning
as intended.
Air bags or Emergency Tensioning Devices
(ETDs), for example, could deploy
inadvertently or fail to deploy in accidents
although the deceleration threshold for air
bag deployment is exceeded. Therefore,
never modify the restraint systems. Do not
tamper with electronic components or their
software.
In this section, you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint system consists of:
R Seat belts
R Child restraint systems
R LATCH-type (ISOFIX) child seat securing
system
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R Air bag system components with the
PASSENGER AIRBAG OFF indicator lamp
The different air bag systems work
independently of each other. The protective
functions of the system work in conjunction
with each other. Not all air bags are always
deployed in an accident.
i For information on infants and children
traveling with you in the vehicle restraint
systems for infants and children, see
"Children in the vehicle" ( Y page 50). SRS (Supplemental Restraint System)
Introduction Supplemental Restraint System (SRS) with:
R
The 6 SRS warning lamp
R Air bags
R Air bag control unit (with crash sensors)38
Occupant safety
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R
Emergency Tensioning Device
for the front
seat belts and the outer seat belts in the
rear
R Seat belt force limiters for the front seat
belts and the outer seat belts in the rear
SRS reduces the risk of occupants coming
into contact with parts of the vehicle's interior
in the event of an accident. It can also reduce
the effect of the forces to which occupants
are subjected during an accident.
SRS warning lamp G
WARNING
The SRS self-check has detected a
malfunction if the 6 SRS indicator lamp:
R does not light up at all
R does not go out after approximately four
seconds after the engine is started
R lights up
after

the engine is started or while
the vehicle is in motion
For your safety, Mercedes-Benz strongly
recommends that you have the system
checked as soon as possible at a qualified
specialist workshop. SRS may otherwise fail
to activate when it is needed in the event of
an accident, which could lead to serious or
fatal injuries. SRS might also be activated
unexpectedly and unnecessarily, which could
also result in injury.
In addition, work carried out improperly on
SRS may render SRS inoperative or cause
unintended air bag deployment. Work on the
SRS system should only be carried out by
qualified specialist personnel. Consult a
qualified specialist workshop.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz Center
for details. USA only: for further information,
contact our Customer Assistance Center at
1-800-FOR-MERCedes (1-800-367-6372).
The 6 SRS warning lamp in the instrument
cluster lights up when the ignition is switched on. It goes out no later than a few seconds
after the engine is started.
SRS
functions are

checked regularly when the
ignition is switched on or the engine is
running. Therefore, malfunctions can be
detected in good time.
Triggering of Emergency Tensioning
Device and air bags During the first stage of a collision, the air bag
control unit evaluates important physical
data relating to vehicle deceleration or
acceleration, such as:
R
duration
R direction
R magnitude
Based on the evaluation of this data, the air
bag control unit pre-emptively triggers the
Emergency Tensioning Device in the first
stage.
If there is an even higher rate of vehicle
deceleration or acceleration in a longitudinal
direction, the front

air bags are also deployed.
Your vehicle has adaptive, two-stage front air
bags. The air bag control unit evaluates
vehicle deceleration or acceleration in the
event of a collision. In the first deployment
stage, the front air bag is filled with enough
propellant gas to reduce the risk of injuries.
The front air bag is fully deployed if a second
deployment threshold is reached within a few
milliseconds.
The Emergency Tensioning Device and air bag
triggering thresholds are variable and are
adapted to the detected rate of deceleration
or acceleration of the vehicle. This process is
pre-emptive in nature. The triggering process
must take place in good time at the start of
the collision.
The rate of vehicle deceleration or
acceleration and the direction of the force are
essentially determined by:
R the distribution of forces during the
collision
R the collision angle Occupant safety
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Belt warning for the driver and front
passenger
Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7 seat belt warning lamp
lights up
for
six seconds each time the engine
is started. It then goes out if the driver and
the front passenger have already fastened
their seat belts.
If the driver's seat belt is not fastened when
the engine is started, an additional warning
tone will sound. This warning tone stops after
a maximum of six seconds or once the
driver's seat belt is fastened.
If after six seconds the driver or front
passenger have not fastened their seat belts
and the doors are closed, the 7 seat belt
warning lamp lights up:
R until the driver's or front passenger's seat
belt is fastened
R if a vehicle speed of 15 mph (25 km/h) is
exceeded, a warning tone also sounds with
increasing intensity for a maximum of
60 seconds or until the driver or front-
passenger seat belt has been fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front-passenger seat belt has still not been
fastened after 60 seconds. The 7 seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed again exceeds 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open. i
For more information on the 7 seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" ( Y page 224).
Emergency Tensioning Devices, seat
belt force limiters G
WARNING
Pyrotechnic ETDs that were activated must be
replaced.
For your safety, when disposing of the
pyrotechnic ETDs always follow our safety
instructions. These are available at any
authorized Mercedes-Benz Center.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise,

the Emergency
Tensioning Device could be triggered in the
event of an accident.
The front seat belts and the outer seat belts
in the rear are equipped with Emergency
Tensioning Devices and seat belt force
limiters.
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
The ETDs do not correct incorrect seat
positions or incorrectly fastened seat belts.
The ETDs do not pull vehicle occupants back
towards the backrest.
The ETDs can only be activated when:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" 6(Y page 39).
R the belt tongue is engaged in the buckle on
each of the front seat belts.
The ETDs on the outside seats in the rear
compartment are triggered independently of
the lock status of the seat belts.
The ETDs are triggered depending on the type
and severity of an accident:
R if, in the event of a head-on or rear-end
collision, the vehicle decelerates or Occupant safety
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passenger front air bag is deactivated.
Should the 4 5 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check
the 4
5 indicator
lamp while driving to make sure the 4
5 indicator lamp is illuminated. If the
4 5 indicator lamp goes out or
remains out, do not transport a child on the
front passenger seat until the system has
been repaired.
A child in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates.
R If you have to place a child in a forward-
facing child restraint on the front passenger
seat, move the seat as far back as possible,
use the proper child restraint
recommended for the age, size and weight
of the child, and secure child restraint with
the vehicle's seat belt according to the
child seat manufacturer's instructions. G
WARNING
Infants and small children should never share
a seat belt

with another occupant. In the event
of an accident, they could be crushed
between the occupant and seat belt.
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.
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 lap/
shoulder belt fits properly without a booster
seat.
When the child restraint is not in use, remove
it from the vehicle or secure it with the seat
belt to prevent the child restraint from becoming a projectile in the event of an
accident.
G
WARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a

vehicle could result in an accident
and/or serious personal injury. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned on these
parts. G
WARNING
Do not carry heavy or hard objects in the
passenger compartment or

trunk unless they
are firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident Children in the vehicle
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Warning notice on the front-passenger sun visor
Warning symbol for a rearward-facing child
restraint system
Do not use a rearward-facing child restraint
system on a seat that is protected by an air
bag installed in front of it.
Air bag deactivation system on the
front-passenger seat
G
WARNING
If the 4 PASSENGER AIRBAG OFF
indicator lamp does not light up when the
child restraint system is installed, the front-
passenger air bag has not been disabled. If
the front-passenger air
bag deploys, the child
could be seriously or even fatally injured.
Proceed as follows:
R do not use a rearward-facing child restraint
system on the front-passenger seat.
R install a rearward-facing child restraint
system on a suitable rear seat.
or R
only use a forward-facing child restraint
system on the front-passenger seat and
move the front-passenger seat to the
rearmost position.
R have the air bag deactivation system
checked at a

qualified specialist workshop.
To ensure that the air bag deactivation system
on the front-passenger seat functions/
communicates correctly, never place objects,
e.g. a cushion, under the child restraint
system. The entire base of the child restraint
system must always rest on the seat cushion.
An incorrectly installed child restraint system
cannot perform its intended protective
function in the event of an accident, and could
lead to injuries. G
WARNING
Do not place electronic devices on the front-
passenger seat, e.g.:
R laptops, when switched on
R mobile phones
R cards with transponders,

e.g. ski passes or
access cards
Signals from electronic equipment can cause
interference in the sensor system of the air
bag deactivation system. This can lead to a
system malfunction. This may cause the
4 PASSENGER AIR BAG OFF indicator
lamp to light up even if no child seat with a
transponder for an air bag deactivation
system is installed. The front-passenger air
bag would not then deploy during an accident.
It is also possible that the 6 SRS warning
lamp lights up and/or the 4 PASSENGER
AIR BAG OFF indicator lamp does not light up
briefly when you turn the key in the ignition
lock to position 2. Children in the vehicle
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Safety Z
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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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