ECU MERCEDES-BENZ B-CLASS HATCHBACK 2015 Manual PDF

fore recommended that you additionally equip
your vehicle with a TIREFIT kit if you fit tyres that do not feature run-flat characteristics, e.g. win-
ter tyres. A TIREFIT kit can be obtained from a
qualified specialist workshop.
Information on changing and fitting a wheel
(Y page 273).
X Stop the vehicle as far away as possible from
traffic on solid, non-slippery and level ground.
X Switch on the hazard warning lamps.
X Secure the vehicle against rolling away
(Y page 145).
X If possible, bring the front wheels into the
straight-ahead position.
X Switch off the drive system.
X Vehicles without KEYLESS-GO: remove the
key from the ignition lock.
X Vehicles with KEYLESS-GO start-function
or KEYLESS-GO: open the driver's door.
The on-board electronics now have status 0.
This is the same as the key having been
removed.
X Vehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (Y page 126).
X Make sure that the passengers are not endan-
gered as they do so. Make sure that no one is
near the danger area while a wheel is being
changed. Anyone who is not directly assisting
in the wheel change should, for example,
stand behind the barrier.
X Get out of the vehicle. Pay attention to traffic
conditions when doing so.
X Close the driver's door.
X Place the warning triangle at a suitable dis-
tance (Y page 248). Observe legal require-
ments. MOExtended tyres (tyres with run-flat
characteristics)
General notes With MOExtended tyres (tyres with run-flat char-
acteristics), you can continue to drive your vehi- cle even if there is a total loss of pressure in one
or more tyres. The affected tyre must not show
any clearly visible damage.
You can recognise MOExtended tyres by the
MOExtended marking which appears on the tyre wall. You will find this marking next to the tyre size designation, the load-bearing capacity and
the speed index.
MOExtended tyres may only be used in conjunc-
tion with an activated tyre pressure monitor.
If a pressure loss warning message appears
in the multifunction display:
R observe the instructions in the display mes-
sages (Y page 209)
R check the tyre for damage
R if driving on, observe the following notes
The driving distance possible in run-flat mode is approximately 80 km when the vehicle is parti-
ally laden and approximately 30 km when the
vehicle is fully laden.
In addition to the vehicle load, the driving dis-
tance possible depends upon:
R vehicle speed
R road condition
R outside temperature
The driving distance possible in run-flat mode
may be reduced by extreme driving conditions/ manoeuvres, or it can be increased through a
moderate style of driving.
The driving distance possible in run-flat mode is
counted from the moment the tyre pressure loss warning appears in the multifunction display.
You must not exceed a maximum speed of
80 km/h.
When replacing one or all tyres, observe the fol-
lowing specifications for your vehicle's tyres:
R size
R type and
R the "MOExtended" mark.
If a tyre has gone flat and cannot be replaced
with an MOExtended tyre, a standard tyre may
be used as a temporary measure. Make sure
that you use the proper size and type (summer
or winter tyre).
Vehicles with MOExtended tyres are not equip-
ped with a TIREFIT kit at the factory. It is there-
fore recommended that you additionally equip
your vehicle with a TIREFIT kit if you fit tyres that do not feature run-flat characteristics, e.g. win-
ter tyres. A TIREFIT kit can be obtained from a
qualified specialist workshop. 250
Flat tyreBreakdown assistance

Charging the 12‑
volt batteryG
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not breathe in any battery gases. Do not
lean over the battery. Keep the batteries out
of the reach of children. Immediately rinse off
battery acid thoroughly with plenty of clean
water and seek medical attention at once. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing 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.
! Only use battery chargers with a maximum
charging voltage of 14.8 V.
! Only charge the battery using the jump-start
connection point.
The jump-starting connection point is in the
engine compartment (Y page 258).
X Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order as
when connecting the donor battery in the
jump-starting procedure (Y page 258).
If the indicator/warning lamps do not light up at
low temperatures, it is very likely that the dis-
charged battery has frozen. In this case you may neither jump-start the vehicle nor charge the
battery. The service life of a battery that has
been thawed may be reduced. The starting char-
acteristics may be impaired, especially at low temperatures. Have the thawed battery
checked at a qualified specialist workshop.
Only charge the installed battery with a battery
charger which has been tested and approved by
Mercedes-Benz. A battery charger unit specially
adapted for Mercedes-Benz vehicles and tested
and approved by Mercedes-Benz is available as an accessory. This device permits charging of
the battery in position. Contact a Mercedes-
Benz Service Centre for information and availa-
bility. Read the battery charger's operating
instructions before charging the battery. High-voltage battery - important
safety notes
G
DANGER
The vehicle's high voltage electrical system is under high voltage. If you modify components
in the vehicle's high-voltage electrical system or touch damaged components, you may be
electrocuted. The components in the vehi-
cle's high-voltage electrical system may be
damaged in an accident, although the damage
is not visible. There is a risk of fatal injury.
Do not touch any high-voltage components
after an accident and never modify the vehi-
cle's high-voltage electrical system. Have the vehicle towed away after an accident and the vehicle's high-voltage electrical system
checked by a qualified specialist workshop. G
WARNING
In the event of a vehicle fire, the internal pres- sure of the high-voltage battery could exceeda critical value. In this case, flammable gas
escapes through a vent valve in the vehicle's
underbody. The gas can ignite. There is a risk
of injury.
Leave the danger area immediately. Secure
the danger area at a suitable distance, whilst
observing legal requirements. 256
BatteriesBreakdown assistance

Recovery
Important safety notes
G
WARNING
Safety relevant functions are restricted or no
longer available if:
R the ignition is switched off
R the brake system or power steering is mal-
functioning
R there is a malfunction in the voltage supply
or the vehicle's electrical system.
When your vehicle is towed, you may require
considerably more effort to steer and brake.
There is a risk of an accident.
In such cases use a rigid towing bar. Before
towing away, make sure the steering moves
freely. G
WARNING
If the steering wheel lock is engaged, the vehi- cle can no longer be steered. There is a risk of
an accident.
Always switch on the ignition when towing
with a tow rope or a towing bar. G
WARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible gross weight of your vehicle, the:
R towing eye may be torn off
R car/trailer combination may swerve or
even overturn
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per- missible gross weight of your vehicle.
Details on the permissible gross vehicle weight
of your vehicle can be found on the vehicle iden-
tification plate (Y page 281). !
When COLLISION PREVENTION ASSIST
PLUS or the HOLD function is activated, the
vehicle brakes automatically in certain situa-
tions. To avoid damage to the vehicle, deac-
tivate these systems in the following or simi-
lar situations:
R when towing away
R in a car wash
! Make sure that the electric parking brake is
released. If the electric parking brake is faulty, visit a qualified specialist workshop.
Mercedes-Benz recommends that you use a
Mercedes-Benz Service Centre for this pur-
pose.
! Only secure the tow rope or towing bar to
the towing eyes. The vehicle may otherwise
be damaged.
! Observe the following points when towing
with a tow rope:
R secure the tow rope on the same side on
both vehicles.
R make sure that the tow rope is not longer
than legally permitted. Mark the tow rope in
the middle, e.g. with a white cloth
(30 x 30 cm). This makes other road users
aware that a vehicle is being towed.
R only secure the tow rope to the towing eye.
R observe the brake lamps of the towing vehi-
cle while driving. Always maintain a dis-
tance so that the tow rope does not sag.
R do not use steel cables or chains to tow
your vehicle. You could otherwise damage
the vehicle.
! Do not use the towing eyes for recovery pur-
poses as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! When towing, pull away slowly and
smoothly. If the tractive power is too high, the
vehicles could be damaged.
! You may tow the vehicle for a maximum of
50km. A towing speed of 50 km/h must not
be exceeded.
For towing distances over 50 km, the front
axle or the entire vehicle must be raised and
transported.
! When towing vehicles with KEYLESS-GO,
use the key instead of the Start/Stop button. The transmission may otherwise shift to posi- tion Pwhen you open the driver's or front- 260
RecoveryBreakdown assistance

The transmission automatically shifts to posi-
tion Pwhen you open the driver's or front-
passenger door or when you remove the key
from the ignition lock. In order to ensure that the
transmission stays in position Nwhen towing
the vehicle, you must observe the following
points:
X On vehicles with KEYLESS-GO or the KEY-
LESS-GO start function: you must use the
key instead of the Start/Stop button
(Y page 127).
X Make sure that the vehicle is stationary.
X Turn the key to position 2in the ignition lock.
X Depress the brake pedal and keep it
depressed.
X Shift the transmission to position N.
X Release the brake pedal.
X Apply the electric parking brake.
X Deactivate tow-away protection (Y page 68).
X Deactivate automatic locking (Y page 187).
X Move the front wheels to the straight-ahead
position.
X Switch on the hazard warning lamps
(Y page 100).
X Turn the key in the ignition lock to position 0
and leave the key in the ignition lock. Transporting the vehicle
All vehicles !
You may only secure the vehicle by the
wheels, not by parts of the vehicle such as
axle or steering components. Otherwise, the
vehicle could be damaged.
X Turn the key to position 2in the ignition lock
(Y page 126).
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 key to position 0in 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 transportation. Electrical fuses
Important safety notes
G
WARNING
If you manipulate, bridge or replace a faulty
fuse with a fuse of a higher amperage, the
electric cables could be overloaded. This may result in a fire. There is a risk of an accident
and injury.
Always replace faulty fuses with specified newfuses of the correct amperage.
Blown fuses must be replaced with fuses of the same rating, which you can recognise by the
colour and fuse rating. The fuse ratings are listed
in the fuse allocation chart.
If the newly inserted fuse also blows, have the
cause traced and rectified at a qualified special- ist workshop, e.g. a Mercedes-Benz Service
Centre.
! 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". Compo-
nents or systems could otherwise be dam-
aged.
The fuses in your vehicle disconnect faulty cir-
cuits. If a fuse blows, all the components on the circuit and their functions will fail. Before replacing a fuse
X Safeguard the vehicle against rolling away
(Y page 145).
X Switch off all electrical consumers.
X Vehicles without KEYLESS-GO: remove the
key from the ignition lock.
X Vehicles with KEYLESS-GO start-function
or KEYLESS-GO: open the driver's door.
The on-board electronics now have status 0.
This is the same as the key having been
removed.
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 Electrical fuses
263Breakdown assistance Z

Storing wheels
Store wheels in a cool, dry and preferably dark
place if they are not being used. Protect the
tyres against oil and grease. Fitting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the electric parking brake manually.
X Move the front wheels to the straight-ahead
position.
X Shift the transmission to position P.
X Switch off the drive system.
X Vehicles without KEYLESS-GO: remove the
key from the ignition lock.
X Vehicles with KEYLESS-GO start-function
or KEYLESS-GO: open the driver's door.
The on-board electronics now have status 0.
This is the same as the key having been
removed.
X Vehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (Y page 126).
X If included in the vehicle equipment, remove
the tyre-change tool kit from the vehicle.
X Safeguard the vehicle against rolling away
(Y page 145).
i Apart from some country-specific variants,
vehicles are not equipped with tyre-changing
tools. Some tools for changing a wheel are
specific to the vehicle. For more information
on which tools are required to perform a
wheel change on your vehicle, consult a quali- fied specialist workshop.
Necessary tyre-changing tools may include,
for example:
R Jack
R Wheel chock
R Wheel wrench Securing the vehicle against rolling
away
If your vehicle is equipped with a wheel chock, it
can be found in the tyre-change tool kit
(Y page 249).
The folding wheel chock is an additional secur-
ing measure to safeguard the vehicle from roll-
ing 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 =. X
Place chocks or other suitable items under
the front and rear of the wheel that is diago-
nally opposite the wheel you wish to change.
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 jack-
ing point of the vehicle. The base of the jack 274
Changing a wheelWheels and tyres