ECU MERCEDES-BENZ B-CLASS 2012 User Guide
[x] Cancel search | Manufacturer: MERCEDES-BENZ, Model Year: 2012, Model line: B-CLASS, Model: MERCEDES-BENZ B-CLASS 2012Pages: 340, PDF Size: 3.09 MB
Page 59 of 340

Problems with the air bag deactivation system
Problem Possible causes/consequences and
M SolutionsThe 45
indicator lamp on the
center console is lit. A special Mercedes-Benz child restraint system with a
transponder for
air
bag deactivation system has been installed to
the front-passenger seat. The front-passenger front air bag has
therefore been disabled as desired. G
WARNING
There is no child restraint system installed on the front-passenger
seat. The air bag deactivation system is malfunctioning.
It is also
possible that the 6 SRS warning lamp lights up and/
or the 45 indicator lamp does not light up briefly when you
switch the ignition on.
There is a risk of injury.
X Remove electronic equipment from the front-passenger seat,
for example:
R
Laptop
R Mobile phone
R Cards with transponders,
such as ski passes or access cards
If the 45 indicator lamp remains lit:
X Visit a qualified specialist workshop. Child-proof locks
Important safety notes G
WARNING
Activate the child-proof locks for the rear
doors and the override switch for the rear
windows when children are travelling in the
vehicle. Otherwise, the children could open
doors or side windows while the vehicle is in
motion and injure themselves or others. 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, Children in the vehicle
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Safety
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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.
Child-proof locks for the rear doors G
WARNING
Children could open a rear door from inside
the vehicle. This could result in serious
injuries or an accident. Therefore, when
children ride in
the rear always secure the rear
doors with the child-proof locks. You can secure each door individually with
the child-proof
locks
on the rear doors. A door
secured with a child-proof lock cannot be
opened from inside the vehicle. When the
vehicle is unlocked, the door can be opened
from the outside.
X To activate: press the child-proof lock
lever up in the direction of arrow :.
X Make sure that the child-proof locks are
working properly.
X To deactivate: press the child-proof lock
lever down in the direction of arrow ;. Override feature for the rear side
windows G
WARNING
When children ride on the vehicle's rear seats,
activate the override switch. Otherwise, the
children could be injured, e.g. by trapping
themselves in the rear side window. X
To activate/deactivate: press button :.
If
indicator lamp is lit, operation of the rear
side windows is disabled. Operation is only
possible using the switches in the driver's
door. If the indicator lamp is off, operation
is possible using the switches in the rear
compartment. Driving safety systems
Overview of driving safety systems
In this section,
you will find information about
the following driving safety systems:
R ABS ( Anti-lock Braking System)
(Y page 64)
R BAS ( Brake Assist System) ( Y page 59)
R COLLISION PREVENTION ASSIST (adaptive
Brake Assist and distance warning signal)
(Y page 60)
R Adaptive brake lights ( Y page 62)
R ESP ®
(Electronic Stability Program)
(Y page 62)
R EBD ( Electronic Brake force Distribution)
(Y page 64) 58
Driving safety systems
Safety
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X
To open a front door: pull door
handle ;.
X To unlock a rear door: pull up locking
knob :.
The door is unlocked and can be opened.
X To open a rear door: pull door handle ;.
You can open a door from inside the vehicle
even if it has been locked. You can open the
rear doors from
inside the vehicle unless they
are secured by the child-proof lock
(Y page 58).
If the vehicle has previously been locked with
the SmartKey, opening a door from the inside
will trigger the anti-theft alarm system.
Switch off the alarm (Y page 65). Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside.
This can be useful if you wish
to lock the vehicle before pulling away, for
example. X
To unlock: press button :.
X To lock: press button ;.
The vehicle locks when all the doors and
the tailgate are closed.
Meanwhile, the fuel filler flap will not be
locked or unlocked.
You cannot unlock the vehicle centrally from
the inside if
the vehicle has been locked with
the SmartKey. You can open a door from inside the vehicle
even if it has been locked. You can open the
rear doors
from
inside the vehicle unless they
are secured by the child-proof lock
(Y page 58).
If the vehicle has previously been locked with
the SmartKey, opening a door from the inside
will trigger the anti-theft alarm system.
Switch off the alarm (Y page 65).
If the vehicle has been locked using the
locking button for the central locking, or has
been locked automatically, and a door is
opened from the inside:
R the vehicle will be fully unlocked if it had
previously been fully unlocked
R only the door which has been opened form
the inside is unlocked if only the driver's
door had been previously unlocked Automatic locking feature
X
To deactivate: press and hold button :
for about five
seconds until a tone sounds.
X To activate: press and hold button ; for
about five seconds until a tone sounds.
i If you press one of the two buttons and
do not
hear
a tone, the relevant setting has
already been selected.
The vehicle is locked automatically when the
ignition is switched on and the wheels are
turning. 74
Doors
Opening and closing
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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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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).Notes on breaking-in a new vehicle
Important safety notes
New and replaced brake pads and discs only
reach their optimum braking effect after
several hundred kilometers of driving.
Compensate for this
by applying greater force
to the brake pedal. The first 1,000miles (1,500 km)
The more you
look after the engine when it is
new, the more satisfied you will be with its
performance in the future.
R You should therefore drive at varying
vehicle and engine speeds for the first
1,000 miles (1,500 km).
R Avoid heavy loads, e.g. driving at full
throttle, during this period.
R Change gear in good time, before the
tachometer needle is Ô of the way to the
red area of the tachometer.
R Do not manually shift to a lower gear to
brake the vehicle.
R If possible, do not depress the accelerator
pedal past the point of resistance
(kickdown).
R Ideally, for the first 1,000 miles (1,500 km),
drive in program E. After 1,000 miles (1,500km), you can
increase the
engine
speed gradually and bring
the vehicle up to full speed.
i You should also observe these notes on
breaking-in if the engine or parts of the
drive train on your vehicle have been
replaced.
i Always observe the respective speed
limits. Driving
Important safety notes
G
WARNING
Objects in the driver's footwell can restrict the
pedal travel or obstruct a depressed pedal.
The operating and road safety of the vehicle
is jeopardized. There is a risk of an accident.
Make sure that all objects in the vehicle are
stowed correctly, and that they cannot enter
the driver's footwell. Install the floormats
securely and as specified in order to ensure
sufficient clearance for
the pedals. Do not use
loose floormats. G
WARNING
Unsuitable footwear can hinder correct usage
of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. 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. 134
Driving
Driving and parking
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Pulling away
Automatic transmission i
It is only
possible to shift the transmission
from position P to the desired position if
you depress the brake pedal. Only then can
the parking lock be deactivated. If you do
not depress the brake pedal, the DIRECT
SELECT lever can still be moved but the
parking lock remains engaged.
i If the transmission oil temperature is
below Ò4 ‡ (Ò20 † ), you can only shift from
position P when the engine is running.
X Depress the brake pedal and keep it
depressed.
X Shift the transmission to position D or R.
X Release the brake pedal.
X Carefully depress the accelerator pedal.
The electric parking brake (Y page 150) is
automatically released.
The red ! indicator lamp in the
instrument cluster goes out.
i The vehicle locks
centrally once you have
pulled away. The locking knobs in the doors
drop down.
You can open the doors from the inside at
any time.
You can also deactivate the automatic
locking feature (Y page 198).
i Upshifts take place at higher engine
speeds after a cold start. This helps the
catalytic converter to reach its operating
temperature more quickly.
Hill start assist G
WARNING
After a short time, hill start assist will no
longer brake your vehicle and it could roll
away. There is
a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never
leave the vehicle when it is held by hill start
assist. Hill start assist helps you when pulling away
forwards or in reverse on an uphill gradient.
It holds the vehicle for a short time after you
have removed
your
foot from the brake pedal.
This gives you enough time to move your foot
from the brake pedal to the accelerator pedal
and to depress it before the vehicle begins to
roll.
X Remove your foot from the brake pedal.
The vehicle is
then held for about a second.
X Pull away.
Hill start assist will not function if:
R you are pulling away on a level road or on
a downhill gradient.
R the transmission is in position N.
R the electric parking brake is applied.
R ESP ®
is malfunctioning.
Further information on holding the vehicle
stationary on uphill gradients ( Y page 143). ECO start/stop function
Important safety notes G
WARNING
If the engine is switched off automatically and
you exit the vehicle, the engine is restarted
automatically. The vehicle
may begin moving.
There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes If the
¤ symbol is shown in the
multifunction display, the ECO start/stop
function switches the engine off
automatically when the vehicle stops.
The engine starts automatically when the
driver wants to pull away again. The ECO
start/stop function thereby helps you to
reduce the fuel consumption and emissions
of your vehicle. 136
Driving
Driving and parking
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Remaining in neutral N
If the automatic transmission is to remain in
neutral N, e.g. for washing the vehicle in car
washes with
a
towing device, please observe
the following instructions: G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shift the automatic transmission out of
parking position P.
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you
and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
R Make sure that the ignition is switched on.
R When the vehicle is stationary, depress the
brake pedal and keep it depressed.
R Shift to neutral N.
R Release the brake pedal.
R If the electric parking brake is engaged,
release it.
R Switch off the ignition and leave the
SmartKey in the ignition lock.
Engaging drive position D X
When the vehicle is stationary, depress the
brake pedal.
X Push the DIRECT SELECT lever down past
the first point of resistance. Transmission positions
B
Park position
Do not shift the transmission into
position P unless the vehicle is
stationary (
Y page 149). The
parking lock should
not be used as
a brake when parking. Always
apply the electronic parking brake
in addition to the parking lock in
order to secure the vehicle.
If the vehicle electronics are
malfunctioning, the transmission
may be locked in position P.
Have the vehicle electronics
checked immediately at a qualified
specialist workshop. C
Reverse gear
Only shift the transmission to
R
when the vehicle is stationary. A
Neutral
No power is transmitted from the
engine to the drive wheels.
Releasing the
brakes
will allow you
to move the vehicle freely, e.g. to
push it or tow it.
If ESP ®
is deactivated or faulty:
only shift the transmission to
position N if the vehicle is in danger
of skidding, e.g. on icy roads.
When you switch off the engine, the
automatic transmission
automatically shifts into neutral N. 7
Drive
The automatic transmission
changes gear automatically. All
forward gears are available.142
Automatic transmission
Driving and parking
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Problems with fuel and the fuel tank
Problem Possible causes/consequences and
M SolutionsFuel is leaking from the
vehicle. The fuel line or the fuel tank is faulty.
G WARNING
Risk of explosion or fire.
X Turn the SmartKey to position 0
in the
ignition lock immediately
and remove it (Y page 135).
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The fuel filler flap
cannot be opened. The fuel filler flap is not unlocked.
or
The SmartKey battery is discharged.
X
Unlock the vehicle (Y page 68).
or
X Unlock the vehicle using the mechanical key ( Y page 69).The fuel filler flap is unlocked, but the opening mechanism is
jammed.
X
Consult a qualified specialist workshop. Parking
Important safety notes
G
WARNING
If flammable materials such as leaves, grass
or twigs are
exposed to prolonged contact to
parts of the exhaust system that heat up, they
could ignite. There is a risk of fire.
Park the vehicle so that no flammable
materials come into contact with parts of the
vehicle which are hot. Take particular care not
to park on dry grassland or harvested grain
fields. G
WARNING
If you leave children unsupervised in the
vehicle, they could set it in motion by, for
example:
R releasing the parking brake
R shifting the automatic transmission out of
the parking position P
R starting the engine.
They could also operate the vehicle's
equipment. There is
a risk of an accident and
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
! Always secure the vehicle correctly
against rolling away. Otherwise, the vehicle
or its drivetrain could be damaged. Parking
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Driving and parking Z
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To ensure that the vehicle is secured against
rolling away unintentionally:
R
the electric parking
brake must be applied.
R the transmission must be in position P and
the transmission position display must
show P.
R the SmartKey must be removed from the
ignition lock.
R on uphill or downhill gradients, the front
wheels must be turned towards the curb. Switching off the engine
Important safety notes G
WARNING
The automatic transmission switches to
neutral position N when you switch off the
engine. The vehicle may roll away. There is a
risk of an accident.
After switching off the engine, always switch
to parking position P. Prevent the parked
vehicle from rolling away by applying the
parking brake.
Vehicles with automatic transmission X
Apply the electric parking brake.
X Shift the transmission to position P.
X Turn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.
i If you switch the engine off with the
transmission in position R or D, the
automatic transmission shifts to N
automatically.
If you then open one of the front doors or
remove the SmartKey
from the ignition, the
automatic transmission shifts to P.
If you shift the automatic transmission to
N before switching off the engine, the
automatic transmission remains in N even
if a door is opened. i
The automatic transmission shifts to P
automatically if you:
R switch off the
engine using the SmartKey
and remove the SmartKey from the
ignition lock or
R switch off the engine using the SmartKey
and open a front door.
If you attempt to turn off the engine when the
selector lever is not in position P:
R a message appears in the multifunction
display
R a warning signal sounds Electric parking brake
General notes G
WARNING
If you leave children unsupervised in the
vehicle, they could set it in motion by, for
example:
R releasing the parking brake
R shifting the automatic transmission out of
the parking position P
R starting the engine.
They could also operate the vehicle's
equipment. There is
a risk of an accident and
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle. i
The electric parking brake performs a
function test at regular intervals while the 150
Parking
Driving and parking
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Front wheel
Rear wheel
X
Bring the vehicle and wheels into a suitable
position so that you can attach test gauge
A.
X Secure the vehicle against rolling away
(Y page 149).
X Move the selector lever to position P.
X Switch off the engine.
X Place test gauge A between the wheel's
spokes on brake pad/lining =. X
Hold test gauge A vertically on brake
disc : and slide measuring pin ; onto
brake disc :.
X Check which color field ? the arrow on
measuring pin ; is pointing to.
Green: the brake pad/lining thickness is
sufficient.
Red: the brake pad/lining thickness is not
sufficient. Have the brake pads/lining
checked at
a
qualified specialist workshop.
i To avoid an inaccurate measurement:
R make sure you position the wheels
suitably
R do not
put
the measuring pin on a recess
in the brake disc Driving on wet roads
Hydroplaning If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if:
R
you drive at low speeds.
R the tires have adequate tread depth.
For this reason, in the event of heavy rain or
in conditions in which hydroplaning may
occur, you must drive in the following
manner:
R lower your speed.
R avoid ruts.
R brake carefully.
Driving on flooded roads !
Do not drive through flooded areas.
Check the depth
of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic
components in the engine or the automatic
transmission. Water can also be drawn in
by the engine's air suction nozzles and this
can cause engine damage. 156
Driving tips
Driving and parking
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