2012 MERCEDES-BENZ B-CLASS engine

Jump-starting
For the jump-starting
procedure, use only the jump-starting connection point, consisting of a
positive terminal and an earth point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not inhale any battery gases. Do not lean over
the battery. Keep children away from batteries. Wash battery acid immediately with water and
seek medical attention. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk
of an explosion.
Particularly avoid fire, open flames, creating sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting. Do not lean over a battery. G
WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important

that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging

the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting. G
WARNING
Non-combusted fuel can collect in the exhaust system and ignite. There is a risk of fire. Avoid
repeated and lengthy starting attempts.
! Avoid repeated and

lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
If, at low temperatures, the indicator lamps/warning lamps in the instrument cluster do not
light up, it is highly likely that the discharged battery has frozen. In this case you may neither
jump-start the vehicle nor charge the battery. The service life of a thawed-out battery may be Jump-starting
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shorter. The starting characteristics can be impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified specialist workshop.
Do not
start
the vehicle using a rapid charging device. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a second battery using jumper
cables. Observe the following points:
R The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible,
jump-start the vehicle using a second battery or a jump-starting device.
R You may only jump-start the vehicle when the engine and exhaust system are cold.
R Do not start the engine if the battery is frozen. Let the battery thaw first.
R Jump-starting may only be performed from batteries with a nominal voltage of 12 V.
R Only use jumper cables which have a sufficient cross-section and insulated terminal clamps.
R If the battery is fully discharged, leave the battery that is being used to jump-start connected
for a few minutes before attempting to start. This charges the battery slightly.
R Make sure that the two vehicles do not touch.
Make sure that:
R the jumper cables are not damaged.
R bare parts of the terminal clamp do not come into contact with other metal parts while the
jumper cables are connected to the battery.
R the jumper cables cannot come into contact with parts which can move when the engine
is running, such as the V-belt pulley or the fan.
X Secure the vehicle by applying 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.
X Switch off all electrical consumers (e.g. radio, blower, etc.).
X Open the hood (Y page 266).290
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Position number
B identifies the charged battery of the other vehicle or an equivalent jump-
starting device.
X Press together cover : of positive clamp ; and slide it back.
X Connect positive terminal ; on your vehicle to positive terminal = of donor battery B
using the jumper cable, beginning with your own battery.
X Start the engine of the donor vehicle and run it at idling speed.
X Connect negative terminal ? of
donor
battery B to ground point A of your vehicle using
the jumper cable, connecting the jumper cable to donor battery B first.
X Start the engine.
X Before disconnecting the jumper cables, let the engine run for several minutes.
X First, remove the jumper cables from earth point A and negative terminal ?, then from
positive clamp ; and positive terminal =. Begin each time at the contacts on your own
vehicle first.
X Close cover : of positive terminal ; after removing the jumper cables.
X Have the battery checked at a qualified specialist workshop.
i Jump-starting is not considered to be a normal operating condition.
i Jumper cables and further information regarding jump-starting can be obtained at any
qualified specialist workshop. Towing and tow-starting
Important safety notes
G
WARNING
Functions relevant to safety are restricted or
no longer available if:
R the engine is not running.
R the brake system or the power steering is
malfunctioning.
R there is a

malfunction in the voltage supply
or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely. G
WARNING
If the weight of the vehicle to be towed or tow-
started is greater than the permissible gross
weight of your vehicle:
R the towing eye could detach itself
R the vehicle/trailer combination could
rollover.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the
permissible gross weight of your vehicle.
Information on your vehicle's gross vehicle
weight rating can be found on the vehicle
identification plate ( Y page 328). G
WARNING
The vehicle is braked if the HOLD function is
activated. Therefore, deactivate HOLD if the
vehicle is to be towed. Towing and tow-starting
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Towing the vehicle with the front axle
raised
! The ignition must be switched off if the
vehicle is being towed with the front axle
raised. Otherwise, ESP®

may intervene and
damage the brake system.
X Turn the SmartKey to position 2 in the
ignition lock.
X When the vehicle is stationary, depress the
brake pedal and keep it depressed.
X Shift the automatic transmission to
position P.
X Release the brake pedal.
X Release the electric parking brake.
X Deactivate automatic locking
(Y page 198).
X Switch on the hazard warning lamps
(Y page 101).
X Turn the SmartKey to position 0 in the
ignition lock and

leave the SmartKey in the
ignition lock.
When towing your vehicle with the front axle
raised, it is important that you observe the
safety instructions ( Y page 291).Towing a vehicle with both axles on
the ground
G
WARNING
The power assistance for the steering and the
brake force booster do not work when the
engine is not running. You will then need
much more effort to brake and steer the
vehicle. Adapt your style of driving
accordingly.
i In order to signal a change of direction
when towing with

the hazard warning lamps
switched on, use the combination switch as
usual. In this case, only the turn signals for
the desired direction flash. When you reset
the combination switch, the hazard
warning lamps start flashing again. The automatic transmission automatically
shifts
to position P

when you open the driver's
or front-passenger door or when you remove
the SmartKey from the ignition lock. In order
to ensure that the automatic transmission
stays in position N when towing the vehicle,
you must observe the following points:
X Make sure that the vehicle is stationary.
X Turn the SmartKey to position 2 in the
ignition lock.
X Depress and hold the brake pedal.
X Shift the automatic transmission to
position N.
X Leave the SmartKey in position 2 in the
ignition lock.
X Release the brake pedal.
X Release the electric parking brake.
X Switch on the hazard warning lamps
(Y page 101).
It is important that you observe the safety
instructions when towing away your vehicle
(Y page 291). Transporting the vehicle
! Only lash the

vehicle down by the wheels
or wheel rims, not by parts of the vehicle
such as axle or steering components.
Otherwise, the vehicle could be damaged.
X Turn the SmartKey to position 2 in the
ignition lock.
X Shift the transmission to position N.
As soon as the vehicle is loaded:
X Prevent the vehicle from rolling away by
applying 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.
X Secure the vehicle.
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transporting
purposes. Towing and tow-starting
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Tow-starting (emergency engine
starting)
! Vehicles with automatic transmission
must not be tow-started. You could
otherwise damage the automatic
transmission.
When tow-starting, it is important that you
observe the safety
instructions (Y page 291).Fuses
Important safety notes
G
WARNING
If you manipulate or bridge a faulty fuse or if
you replace it with a fuse with a higher
amperage, the electric cables could be
overloaded. This could result in a fire. There
is a risk of an accident and injury.
Always replace faulty

fuses with the specified
new fuses having the correct amperage.
! Only use fuses that have been approved
for Mercedes-Benz vehicles and which
have the correct fuse rating for the system
concerned. Only use fuses marked with an
"S". Otherwise, components or systems
could be damaged.
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the
components on the circuit and their functions
stop operating.
Blown fuses must be replaced with fuses of
the same rating, which you can recognize by
the color and value. The fuse ratings are listed
in the fuse allocation chart.
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center. Before changing a fuse
X Secure the vehicle against rolling away
(Y page 149).
X Switch off all electrical consumers.
X Turn the SmartKey to position 0 in the
ignition lock and remove it (Y page 135).
All indicator lamps

in the instrument cluster
must be off.
The fuses are located in various fuse boxes:
R Fuse box in

the engine compartment on the
left-hand side of the vehicle, when viewed
in the direction of travel
R Fuse box in the front-passenger footwell
The fuse allocation chart is on the fuse box in
the front-passenger footwell ( Y page 295). Fuse box in the engine compartment
G
WARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured
by the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
! Make sure that

no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture
seeping in or dirt could otherwise impair
the operation of the fuses. 294
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X
Switch off the engine.
X Remove the SmartKey from the ignition
lock.
X If included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle.
X Secure the vehicle to prevent it from rolling
away.
Securing the vehicle to prevent it from
rolling away If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(Y page 280).
The folding wheel chock is an additional
safety measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
X
Fold both plates upwards :.
X Fold out lower plate ;.
X Guide the lugs on the lower plate fully into
the openings in base plate =.Securing the vehicle on level ground X
On level ground: place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change. Securing the vehicle on slight downhill gradients
X
On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate
jacking point of the vehicle. The base of the
jack must be positioned vertically, directly
under the jacking point of the vehicle.
The following must be observed when
raising the vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used
incorrectly, the jack
could tip over with the
vehicle raised.
R the jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for
performing maintenance work under the
vehicle.
R avoid changing the wheel on uphill and
downhill slopes.320
Changing a wheel
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R
before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Never
disengage the parking brake while the
vehicle is raised.
R the jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, load-bearing underlay
must be used.
On a slippery surface, a non-slip underlay
must be used, e.g. rubber mats.
R do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R make sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 inches (3 cm).
R never place your hands and feet under the
raised vehicle.
R never lie under the raised vehicle.
R never start the engine when the vehicle is
raised.
R never open or close a door or the trunk lid
when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised.
! The jack is designed exclusively for
jacking up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged. X
Using lug wrench :, loosen the bolts on
the wheel you

wish to change by about one
full turn. Do not unscrew the bolts
completely. The jacking points are located just behind the
wheel housings of the front wheels and just
in front of the wheel housings of the rear
wheels (arrows).
X
Take the ratchet wrench out of the tire-
changing tool kit and place it on the
hexagon nut of the jack so that the letters
AUF are visible. X
Position jack = at jacking point ;. X
Make sure the foot of the jack is directly
beneath the jacking point. Changing a wheel
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applicable to your vehicle on the vehicle
identification plate.
VIN
X
Slide the right-hand front seat to its
rearmost position.
X Fold up floor covering : in front of the
right-hand front seat.
You will see VIN ;.
The VIN can also be found in the following
locations:
R on the lower edge of the windshield
(Y page 329)
R on the vehicle identification plate
(Y page 328) Engine number
:
Emissions control information plate
; Engine number (stamped into the
crankcase)
= VIN (on the lower edge of the windshield) Service products and filling
capacities
Important safety notes
G
WARNING
Service products may be poisonous and
hazardous to health. There is a risk of injury.
Comply with instructions on the use, storage
and disposal of
service products on the labels
of the respective original containers. Always
store service products sealed in their original
containers. Always keep service products out
of the reach of children. H
Environmental note
Dispose of service products in an
environmentally responsible manner.
Service products include the following:
R Fuels
R Lubricants (e.g. engine

oil, transmission oil)
R Coolant
R Brake fluid
R Windshield washer fluid
R Climate control system refrigerant
Components and service products must be
matched. You should therefore only use
products that have been tested and approved
by Mercedes-Benz.
Information about tested and approved
products can be obtained from an authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
You can recognize service products approved
by Mercedes-Benz by the following
inscription on the containers:
R MB-Freigabe (e.g. MB-Freigabe 229.51)
R MB Approval (e.g. MB Approval 229.51)
Other designations or recommendations
indicate a level of quality or a specification in
accordance with an MB Sheet number (e.g.
MB 229.5). They have not necessarily been
approved by Mercedes-Benz. Service products and filling capacities
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