ECU MERCEDES-BENZ B-CLASS HATCHBACK 2015 Repair Manual

Tyres
Problem
Possible causes/consequences and
M
MSolutions h
The yellow tyre pressure
monitor warning lamp
(pressure loss/malfunc-
tion) is lit.
The tyre pressure monitor has detected a loss of pressure in at least
one of the tyres.
G WARNING
Underinflated tyres pose the following risks:
R the tyres may burst, especially as the load and vehicle speed
increase
R the tyres may wear excessively and/or unevenly, which may greatly
impair tyre traction
R the driving characteristics, as well as steering and braking, may be
greatly impaired
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 145).
X Observe the additional display messages in the multifunction dis-
play.
X Check the tyres and, if necessary, follow the instructions for a flat
tyre (Y page 249).
X Check the tyre pressure (Y page 270).
X If necessary, correct the tyre pressure. h
The yellow tyre pressure
monitor warning lamp
(pressure loss/malfunc-
tion) flashes for approx-
imately one minute and
then remains lit.
The tyre pressure monitor is faulty.
G WARNING
The system is possibly unable to detect or register low tyre pressure.
There is a risk of an accident.
X Observe the additional display messages in the multifunction dis-
play.
X Consult a qualified specialist workshop immediately. Warning and indicator lamps in the instrument cluster
223On-board computer and displays Z

Useful information
i This Owner's Manual describes all models,
series and optional equipment for your vehi-
cle that were available at the time of going to
press. National variations are possible. Note
that your vehicle may not be equipped with all
of the functions described. This is also the
case for systems and functions relevant to
safety.
i Read the information on qualified specialist
workshops: (Y page 23). Loading guidelines
G
WARNING
If objects, luggage or loads are not secured or not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, especially when braking or abruptly changing directions.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
The handling characteristics of a laden vehicle
are dependent on the distribution of the load
within the vehicle. For this reason, you should
observe the following notes when transporting a load:
R never exceed the maximum permissible gross
vehicle weight or the permissible axle loads
for the vehicle (including occupants).
R the luggage compartment is the preferred
place to carry objects.
R position heavy loads as far forwards as pos-
sible and as low down in the load compart-
ment as possible.
R the load must not protrude above the upper
edge of the seat backrests.
R always place the load against the rear or front
seat backrests. Make sure that the seat
backrests are securely locked into place.
R always place the load behind unoccupied
seats if possible.
R use the lashing eyelets and the luggage nets
to transport loads and luggage. R
only use lashing eyelets and fastening com-
ponents that are suitable for the weight and
size of the load.
R hook in the safety net when loading.
R the maximum load capacity of the stowage
well under the luggage compartment floor is
25 kg.
R secure the load with sufficiently strong and
wear-resistant lashing material. pad sharp
edges for protection.
! Do not position the load on one part of the
folding luggage compartment floor only. The
maximum load capacity of the folding luggage compartment floor is 100 kg. Spread the
weight evenly to avoid damaging the luggage
compartment floor. Place a solid board under the load if necessary. Please note that the
load on the luggage compartment floor will be increased when the load is lashed down. Stowage areas
Stowage compartments
Important safety notes G
WARNING
If objects in the passenger compartment are
stowed incorrectly, they can slide or be
thrown around and hit vehicle occupants.
There is a risk of injury, particularly in the
event of sudden braking or a sudden change
in direction.
R Always stow objects so that they cannot be
thrown around in such situations.
R Always make sure that objects do not pro-
trude from stowage spaces, parcel nets or
stowage nets.
R Close the lockable stowage spaces before
starting a journey.
R Stow and secure objects that are heavy,
hard, pointed, sharp-edged, fragile or too
large in the luggage compartment.
Observe the loading guidelines (Y page 224).224
Stowage areasStowing and features

Stowage compartment/telephone com-
partment under the armrest X
To open: on vehicles with moveable armr-
ests, make sure that the armrest is in the
rearmost position.
X Press button :and fold the armrest up.
Depending on the vehicle equipment, the arm-
rest can be moved backwards or forwards in a
longitudinal direction.
Depending on the vehicle's equipment, the fol-
lowing may be in the stowage space:
R a multimedia connector unit with an SD card
slot and 2 USB ports, e.g. for use with an
iPod ®
, iPhone ®
or MP3 player; see the sepa-
rate operating instructions
R a mobile phone bracket (Y page 236)
Stowage compartment under the driver's and front-passenger seat G
WARNING
If you exceed the maximum permitted load of the stowage compartment, the cover is
unable to restrain the objects. Objects may be
thrown out of the stowage compartment and
hit vehicle occupants as a result. There is a
risk of injury, particularly in the event of sud-
den braking or a sudden change in direction.
Always observe the maximum load of the
stowage compartment. Stow and secure
heavy objects in the luggage compartment.
The maximum permissible load of the stowage
compartment is 1.2 kg. X
To open: pull handle :up and fold cover ;
forwards.
On vehicles with a fire extinguisher instead of a
stowage compartment, the fire extinguisher is
installed under the driver's seat.
Rear stowage compartments Stowage compartment in the rear centre
console
X
To open: pull down the top of stowage com-
partment :by the edge of the handle.
i Depending on the vehicle's equipment,
there may be an open stowage space above
the stowage compartment.
Folding table G
WARNING
If the folding table is folded out while the vehi- cle is in motion, vehicle occupants may collide with the table, particularly in the event of an
accident, heavy braking or sudden changes in
direction. There is a risk of injury.
Fold up the folding table before every journey. 226
Stowage areasStowing and features

X
Move the driver's or front-passenger seat
forward if necessary.
X Fold seat backrest :back until it engages.
Red lock status indicator ;is no longer visi-
ble.
X Adjust the head restraints if necessary
(Y page 89).
X Move the driver's or front-passenger seat
back if necessary. Securing a load
Lashing eyelets General notes
Observe the following notes on securing loads:
R observe the loading guidelines (Y page 224).
R secure the load using the lashing eyelets.
R distribute the load on the lashing eyelets
evenly.
R do not use elastic straps or nets to secure a
load. These are only intended as an anti-slip
protection for light loads.
R do not route lashing materials across sharp
edges or corners.
R pad sharp edges for protection.
Luggage compartment :
Lashing eyelets
Bag hook G
WARNING
The bag hooks cannot restrain heavy objects
or items of luggage. Objects or items of lug-
gage could be flung around and thereby hit vehicle occupants when braking or abruptly
changing directions. There is a risk of injury.
Only hang light objects on the bag hooks.
Never hang hard, sharp-edged or fragile
objects on the bag hooks.
! The bag hook can bear a maximum load of
3 kg. Do not use it to secure a load. :
Bag hook Luggage compartment cover
Important safety notes G
WARNING
On its own, the luggage compartment cover
cannot secure or restrain heavy objects,
items of luggage and heavy loads. You could
be hit by an unsecured load during sudden
changes in direction, braking or in the event of an accident. There is an increased risk of
injury or even fatal injury.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping over, e.g. by
using lashing material, even if you are using
the luggage compartment cover.
! When loading the vehicle, make sure that
you do not stack the load in the luggage com- partment higher than the lower edge of the
side windows. Do not place heavy objects ontop of the luggage compartment cover.
! When removing and replacing the luggage
compartment cover, ensure that its end caps do not scrape the light-coloured parts of the
vehicle. Stowage areas
229Stowing and features Z

The luggage compartment cover is located
behind the rear bench seat backrest.
Extending and retracting the luggage
compartment cover X
To extend: pull the luggage compartment
cover back by grab handle :and clip it into
retainers ;on the left and right.
X To retract: unhook the luggage compartment
cover from retainers ;on the left and right
and guide it forwards by grab handle :until
it is fully retracted.
Fitting/removing the luggage compart-
ment cover X
To remove: make sure that the luggage com-
partment cover is rolled up.
X Push in the end cap of luggage compartment
cover :in the direction of the arrow on the
right or left-hand side using grip =on the
lower edge.
X Push luggage compartment cover :into
opposite anchorage ;.
X Remove luggage compartment cover :
upwards. X
To fit: place luggage compartment cover :
into anchorage ;on the right or left-hand
side.
X Push in the opposite end cap of luggage com-
partment cover :and insert luggage com-
partment cover :into opposite anchor-
age ;. Safety net
Important safety notes G
WARNING
On its own, the safety net cannot secure or
restrain heavy objects, items of luggage and
heavy loads. You could be hit by an unsecured load during sudden changes in direction,
braking or in the event of an accident. There isan increased risk of injury or even fatal injury.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping over, e.g. by
using lashing material, even if you are using
the safety net.
It is important to use a safety net if you load the
vehicle with small objects above the seat backr-
ests. For safety reasons, always use a safety net when transporting a load.
Damaged safety nets can no longer fulfil their
protective function and must be replaced. Visit a qualified specialist workshop.
Attaching and tightening the safety net You have two options for hooking in the safety
net:
R with luggage compartment enlargement: the
brackets are behind the B‑pillar and the lash-
ing eyelets to tension the net are on the sides
of the rear-compartment footwell.
R without luggage compartment enlargement:
the brackets are behind the C-pillar and the
lashing eyelets to tension the net are in the
luggage compartment (Y page 229).
The safety net is located in the stowage space
under the luggage compartment floor
(Y page 231). 230
Stowage areasStowing and features

X
Attach hook =to the luggage compart-
ment's upper seal ?.
X To close: detach hook =from upper seal ?.
X Fasten hook =to the bracket on the under-
side of the luggage compartment floor.
X Fold the luggage compartment floor down.
X Press the luggage compartment floor down
until it engages.
Setting the height of the luggage com-
partment floor The stowage well under the luggage compart-
ment floor can be increased or decreased in size
as necessary. To do this, you can lock the floor
at two different heights. The upper catch gives a
flat load surface when the rear bench seat is
folded forward. X
To raise: using handle :, lift up luggage
compartment floor ;in the direction of
arrow =and pull it upwards.
X Lower luggage compartment floor ;again.
To do this, push the luggage compartment
floor away so that it engages in the guide on
the upper level.
Luggage compartment floor ;engages in
the upper position. i
Carry out this step using both hands.
X To lower: raise luggage compartment
floor ;slightly using handle :and pull it
towards you.
X Lower luggage compartment floor ;again
slowly. Whilst doing so, press the luggage
compartment floor into the lower level.
Luggage compartment floor ;engages in
the lower position. Roof carrier
Important safety notes G
WARNING
When a load is transported on the roof, the
vehicle's centre of gravity rises and the han-
dling changes. If you exceed the maximum
roof load, the handling as well as steering and braking characteristics are severely affected.
There is a risk of an accident.
Always observe the maximum roof load and
adapt your driving style.
You will find information on the maximum roof
load in the "Technical data" section
(Y page 284).
An incorrectly secured roof carrier or roof load
may become detached from the vehicle. You
must therefore ensure that you observe the roof
carrier manufacturer's installation instructions.
Attaching the roof carrier X
Open covers :carefully in the direction of
the arrow.
X Fold covers :upwards. 232
Stowage areasSto
wing an d features

X
Only secure the roof carrier to the anchorage
points under covers :.
X Observe the manufacturer's installation
instructions. Features
Cup holders
Important safety notes G
WARNING
The cup holder cannot secure a drinks con-
tainer in place during a journey. If you use a
cup holder during a journey, the drinks con-
tainer could be flung around and liquid could
be spilt. Vehicle occupants could come into
contact with the liquid and, in particular, be
scalded by hot liquid. You could be distracted
from the traffic situation and lose control of
the vehicle. There is a risk of an accident and
injury.
Only use the cup holder when the vehicle is
stationary. Only place containers of a suitable size in the cup holder. Seal the container, in
particular when it contains hot liquid. G
WARNING
If objects in the passenger compartment are
stowed incorrectly, they can slide or be
thrown around and hit vehicle occupants.
There is a risk of injury, particularly in the
event of sudden braking or a sudden change
in direction.
R Always stow objects so that they cannot be
thrown around in such situations.
R Always make sure that objects do not pro-
trude from stowage spaces, parcel nets or
stowage nets.
R Close the lockable stowage spaces before
starting a journey.
R Stow and secure objects that are heavy,
hard, pointed, sharp-edged, fragile or too
large in the luggage compartment. !
Only use the cup holders for containers of
the right size and which have lids. The drinks
could otherwise spill.
Observe the loading guidelines (Y page 224).
The stowage compartments in the doors provide
space for bottles:
R front: capacity up to 1.5 l
R rear: capacity up to 0.5 l
Cup holders in the front centre console The cup holder and the rubber mat underneath
can be removed for cleaning. Clean them with
clean, lukewarm water only.
X To remove: carefully pull in upper sections of
cup holder :on the driver's and front-
passenger sides until they release.
X Lift the cup holder up ;until it can be
removed. X
To fit: insert cup holder into lateral curved
sections ;in the stowage compartment.
Insert the cup holder so that the wedge of the upper section of cup holder :faces for-
wards.
X Press the cup holder downwards until it
engages on the right and left-hand sides. Features
233Stowing and features Z

Mobile phone bracket in the stowage
compartment You can fold the pre-installed bracket up to
improve access to the stowage space beneath
it.
Further information about the stowage com-
partment (Y page 226).
X To fold the bracket up: press button:.
X To fold the bracket down: press the bracket
down and allow it to engage. Floormats
G
WARNING
Objects in the driver's footwell may restrict
the clearance around the pedals or block a
depressed pedal. This jeopardises the oper-
ating and road safety of the vehicle. There is a risk of an accident.
Stow all objects securely in the vehicle so that
they do not get into the driver's footwell.
Always fit the floormats securely and as pre-
scribed in order to ensure that there is always sufficient room for the pedals. Do not use
loose floormats and do not place several floor- mats on top of one another. X
Slide the seat backwards.
X To fit: lay the floormat in the footwell.
X Press safety catch knobs :onto retain-
ers ;.
X To remove: pull the floormat away from
retainers ;.
X Remove the floormats. Retrofitted anti-glare film
Retrofitted anti-glare film on the inside of the
windows can interfere with radio/mobile tele-
phone reception. This is particularly the case for conductive or metallic-coated films. You can
obtain information about anti-glare film from a
qualified specialist workshop. 238
FeaturesStowing and features

Always switch off the windscreen wipers and
the ignition before cleaning the windscreen or wiper blades.
! Only fold the windscreen wipers away from
the windscreen when vertical. Otherwise, you
will damage the bonnet.
! Do not use dry cloths, abrasive products,
solvents or cleaning agents containing sol-
vents to clean the inside of the windows. Do
not touch the insides of the windows with
hard objects, e.g. an ice scraper or ring. There is otherwise a risk of damaging the windows.
! Clean the water drainage channels of the
windscreen and the rear window at regular
intervals. Deposits such as leaves, petals and pollen may under certain circumstances pre-
vent water from draining away. This can lead
to corrosion damage and damage to elec-
tronic components.
X Clean the inside and outside of the windows
with a damp cloth and a cleaning agent that is
recommended and approved by Mercedes-
Benz.
Cleaning the wiper blades G
WARNING
If the windscreen wipers are set in motion
when cleaning the windscreen or wiper
blades, you could become trapped. There is a danger of injury.
Always switch off the windscreen wipers and
the ignition before cleaning the windscreen or wiper blades.
! Only fold the windscreen wipers away from
the windscreen when vertical. Otherwise, you
will damage the bonnet.
! Do not pull on the wiper blade. Otherwise,
the wiper blade could be damaged.
! Do not clean wiper blades too often and do
not rub them too hard. Otherwise, the graph- ite coating could be damaged. This could
cause wiper noise.
! Hold the wiper arm securely when folding
back. The windscreen could be damaged if
the wiper arm hits against it suddenly. X
Fold the wiper arms away from the wind-
screen.
X Clean the wiper blades carefully using a damp
cloth.
X Fold the windscreen wipers back again before
switching on the ignition.
Cleaning the exterior lighting !
Only use cleaning agents or cleaning cloths
that are suitable for plastic lenses. Unsuitable
cleaning agents or cleaning cloths could
scratch or damage the plastic lenses of the
exterior lighting.
X Clean the plastic lenses of the exterior light-
ing using a wet sponge and a mild cleaning
agent, e.g. Mercedes-Benz car shampoo or
cleaning cloths.
Cleaning the mirror turn signal !
Only use cleaning agents or cleaning cloths
that are suitable for plastic lenses. Unsuitable
cleaning agents or cleaning cloths could
scratch or damage the plastic lenses of the
mirror turn signals.
X Clean the plastic lenses of the mirror turn sig-
nals in the exterior mirror housing using a wet sponge and mild cleaning agent, e.g.
Mercedes-Benz car shampoo or cleaning
cloths.
Cleaning the sensors !
If you clean the sensors with a high-pressure
cleaner, make sure that you keep a distance
of at least 30 cm between the vehicle and the high-pressure cleaner nozzle. Information
about the correct distance is available from
the equipment manufacturer. Care
245Maintenance and care Z

Useful information
i This Owner's Manual describes all models,
series and optional equipment for your vehi-
cle that were available at the time of going to
press. National variations are possible. Note
that your vehicle may not be equipped with all
of the functions described. This is also the
case for systems and functions relevant to
safety.
i Read the information on qualified specialist
workshops: (Y page 23). Where will I find...?
Warning triangle
Removing/replacing the warning trian-
gle X
To remove: open the tailgate.
X Lift the luggage compartment floor upwards
(Y page 231).
X To release warning triangle :, push back the
retainers on the bracket.
X Remove warning triangle :from the bracket.
X To replace: place warning triangle :back
into the bracket and push down to secure.
X Fold down the luggage compartment floor.
X Close the tailgate. Setting up the warning triangle X
Fold feet =out to the side.
X Fold side reflectors ;upwards to form a tri-
angle and lock them at the top using press
stud :. First-aid kit
X
Open the tailgate.
X To open the stowage compartment: turn
rotary knob :clockwise and fold down
cover ;. X
Remove first-aid kit =.248
Where will I find...?Breakdown assistance