battery MERCEDES-BENZ B-CLASS HATCHBACK 2014 Service Manual

After washing the vehicle, brake carefully
while paying attention to the traffic conditions in order to restore full braking efficiency.
! When DISTRONIC PLUS or the HOLD
function is activated, the vehicle brakes
automatically in certain situations.
To avoid damage to the vehicle, deactivate DISTRONIC PLUS and the HOLD function in the following or similar situations:
R when towing away
R in a car wash
! Make sure that the automatic transmis-
sion is in position Nwhen washing your
vehicle in a tow-through car wash. The vehi-
cle could be damaged if the transmission is
in another position.
! Make sure that:
R the side windows and sliding sunroof are
closed completely.
R the blower for the ventilation/heating is
switched off (OFF button is depressed/
airflow control is turned to position 0).
R the windscreen wiper switch is at posi-
tion 0.
The vehicle could otherwise be damaged.
You can wash the vehicle in an automatic car wash from the very start.
Wash off excess dirt before cleaning the vehi-
cle in an automatic car wash.
After using an automatic car wash, wipe off
wax from the windscreen and the wiper
blades. This will prevent smears and reduce
wiping noises caused by residue on the wind- screen.
Washing by hand In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements for each indi-
vidual country. X
Do not use hot water and do not wash the
vehicle in direct sunlight.
X Use a soft sponge to clean.
X Use a mild cleaning agent, such as a car
shampoo approved by Mercedes-Benz.
X Thoroughly hose down the vehicle with a
gentle jet of water.
X Do not point the water jet directly towards
the air inlet.
X Use plenty of water and rinse out the
sponge frequently.
X Rinse the vehicle with clean water and dry
thoroughly with a chamois.
X Do not let the cleaning agent dry on the
paintwork.
When using the vehicle in winter, remove all
traces of road salt deposits carefully and as
soon as possible.
High-pressure cleaning equipment G
WARNING
The water jet of circular-jet nozzles (dirt grind- ers) can cause damage not visible from the
outside to tyres or chassis components. Com-
ponents damaged in this way can unexpect-
edly fail. There is a risk of an accident.
Do not use high-pressure cleaners with circu-
lar-jet nozzles to clean the vehicle. Have dam- aged tyres or chassis components replaced
immediately.
! Always maintain 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.
Move the high-pressure cleaner nozzle
around when cleaning your vehicle.
Do not aim directly at any of the following:
R tyres
R door gaps, roof gaps, joints etc.
R electrical components
R battery
R connectors Care
325Maintenance and care Z

Useful information
............................332
Where will I find...? ...........................332
Flat tyre ............................................. 334
Battery (vehicle) ................................ 338
Jump-starting .................................... 342
Towing away and tow-starting ........344
Electrical fuses ................................. 349 331Breakdown assistance

X
Stow the tyre sealant bottle, the tyre infla-
tion compressor and the warning triangle.
X Pull away immediately.
X Stop after driving for approximately ten
minutes and check the tyre pressure with
the tyre inflation compressor.
The tyre pressure must now be at least
130 kPa (1.3 bar/19 psi). G
WARNING
If the required tyre pressure is not reached
after driving for a short period, the tyre is too badly damaged. The tyre sealant cannot
repair the tyre in this instance. Damaged tyres and a tyre pressure that is too low can signif-
icantly impair the vehicle's braking and driv-
ing characteristics. There is a risk of accident.
Do not continue driving. Contact a qualified
specialist workshop.
i In your vehicle, you will find a sticker with
the Mercedes-Benz Service24h telephone
number, e.g. on the B-pillar on the driver's
side.
X Correct the tyre pressure if it is still at least
130 kPa (1.3 bar/19 psi). See the fuel filler
flap for values.
X To increase the tyre pressure: switch on
the tyre inflation compressor. X
To reduce the tyre pressure: depress
pressure release button :next to pres-
sure gauge ;.
X When the tyre pressure is correct, unscrew
the filler hose from the valve of the sealed
tyre.
X Screw the valve cap onto the tyre valve of
the sealed tyre. X
To remove the tyre sealant bottle from the
tyre inflation compressor, press together
the locking tabs on the yellow cap.
X Pull the tyre sealant bottle out of the tyre
inflation compressor.
The filler hose stays on the tyre sealant
bottle.
X Drive to the nearest qualified specialist
workshop and have the tyre changed there.
X Have the tyre sealant bottle and the filler
hose replaced as soon as possible at a
qualified specialist workshop.
X Have the tyre sealant bottle replaced every
four years at a qualified specialist work-
shop. Battery (vehicle)
Important safety notes
Work on the battery, e.g. removing or fitting,
requires specialist knowledge and the use of
special tools. Therefore, always have work on the battery carried out at a qualified specialist
workshop. 338
Battery (vehicle)Breakdown assistance

G
WARNING
Work carried out incorrectly on the battery
can lead, for example, to a short circuit and
thus damage the vehicle electronics. This can lead to function restrictions applying to
safety-relevant systems, e.g the lighting sys-
tem, the ABS (anti-lock braking system) or the
ESP ®
(Electronic Stability Program). The oper-
ating safety of your vehicle may be restricted.
You could lose control of the vehicle, for
example:
R when braking
R in the event of abrupt steering manoeuvres
and/or when the vehicle's speed is not
adapted to the road conditions
There is a risk of an accident.
In the event of a short circuit or a similar inci- dent, contact a qualified specialist workshop
immediately. Do not drive any further. Always have work on the battery carried out at a
qualified specialist workshop.
Further information about ABS (Y page 73)
and ESP ®
(Y page 77). G
WARNING
Electrostatic build-up can lead to the creation of sparks, which could ignite the highly explo-
sive gases of a battery. There is a risk of an
explosion.
Before handling the battery, touch the vehicle body to remove any existing electrostatic
build-up.
The highly flammable gas mixture is created
while the battery is charging and when jump-
starting.
Always make sure that neither you nor the
battery is electrostatically charged. Electro-
static charge is created, for example:
R by wearing synthetic fibre clothing
R due to friction between clothing and the
seat R
when you pull or push the battery across
carpet or other synthetic materials
R when you rub the battery with a cloth G
WARNING
During the charging process, a battery produ- ces 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 con-
tact with vehicle parts.
R Never place metal objects or tools on a bat-
tery.
R It is important that you observe the descri-
bed 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 dis-
connecting the jump leads.
R Never connect or disconnect the battery
terminals while the engine is running. 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. H
Environmental note Batteries contain pollutants.
It is illegal to dispose of them
with the household rubbish.
They must be collected sep-
arately and disposed of in anenvironmentally responsible
recycling system. Dispose of batteries in an
environmentally responsible Battery (vehicle)
339Breakdown assistance
Z

manner. Take discharged
batteries to a qualified spe-
cialist workshop or to a col-
lection point for used batter-
ies.
! Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Service
Booklet or contact a qualified specialist
workshop for more information.
! You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery yourself, make sure that:
R you switch off the engine and remove the
key. On vehicles with KEYLESS-GO,
ensure that the ignition is switched off.
Check that all the indicator lamps in the
instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
R in vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be fitted securely dur- ing operation.
Comply with safety precautions and take pro-
tective measures when handling batteries. WARNING
Fire, naked flames and smoking
are prohibited when handling the
battery. Avoid creating sparks. Battery acid is caustic. Avoid con-
tact with the skin, eyes or clothing.
Wear suitable protective clothing,
in particular gloves, an apron and a
face mask.
Immediately rinse acid splashes
off with clean water. Consult a doc-
tor if necessary. Wear eye protection.
Keep children away.
Observe this Owner's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehi-
cle occupants from suffering acid burns
should the battery be damaged in the event of
an accident.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the
vehicle. In such cases, have the battery dis-
connected at a qualified specialist workshop. You can also charge the battery with a
charger recommended by Mercedes-Benz.
For more information, please contact a quali-
fied specialist workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked up for a long period of time.
i When you park the vehicle, remove the
key if you do not require any electrical con- 340
Battery (vehicle)Breakdown assistance

sumers. The vehicle will then use very little
energy, thus conserving battery power.
i If the power supply has been interrupted,
e.g. if the battery was discharged, you will
have to:
R set the clock via Audio 20 or COMAND
Online; see the separate operating
instructions
R reset the function for folding the exterior
mirrors in/out automatically, by folding
the mirrors out once (Y page 116).Charging the battery
G
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 maxi-
mum 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 342).
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 342).
If the indicator/warning lamps do not light up at low temperatures, it is very 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 bat-
tery that has been thawed may be reduced.
The starting characteristics may be impaired,
especially at low temperatures. Have the
thawed battery checked at a qualified spe-
cialist workshop.
Only charge the installed battery with a bat-
tery 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 availability. Read
the battery charger's operating instructions
before charging the battery. Battery (vehicle)
341Breakdown assistance Z

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 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
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
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 jump leads.
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.
! Vehicles with a petrol engine:
avoid repeated and lengthy starting attempts. Otherwise,
the non-combusted fuel may damage the catalytic converter.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the
discharged battery has frozen. In this case you may neither jump-start the vehicle nor charge
the battery. Let the battery thaw first. The service life of a battery that has been thawed may
be reduced. The starting characteristics may be impaired, especially at low temperatures.
Have the thawed battery checked at a qualified specialist workshop. 342
Jump-startingBreakdown assistance

Do not use a rapid charging device to start the vehicle. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a second battery using jump
leads. 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 Vehicles with a petrol engine: 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 using batteries with a nominal voltage of 12 V.
R Only use jump leads that are not damaged and have a sufficient cross-section and insulated
terminal clamps.
R Make sure that the two vehicles do not touch.
Make sure that:
R the jump leads are not damaged.
R non-insulated parts of the terminal clamps do not come into contact with other metal parts
while the jump leads are connected to the battery.
R the jump leads 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 Manual transmission: depress the clutch pedal fully and shift to neutral.
X Automatic transmission: shift the transmission to position P.
X Turn the key to position 0in the ignition lock and remove it.
X Switch off all electrical consumers, e.g. rear window heating, lighting etc.
X Open the bonnet. Jump-starting
343Breakdown assistance Z

Position number
Bidentifies 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 jump lead, 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 Bto earth point Aof your vehicle using the
jump lead, connecting the jump lead to donor battery Bfirst.
X 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 empty battery a little.
X Start the engine.
X Before disconnecting the jump leads, let the engines run for several minutes.
X First, remove the jump leads from earth point Aand negative terminal ?, then from pos-
itive clamp ;and positive terminal =. Begin each time at the contacts on your own vehicle
first.
X Close cover :of positive clamp ;after removing the jump leads.
X Close the bonnet.
X Have the battery checked at a qualified specialist workshop.
i Jump-starting is not considered to be a normal operating condition.
i Jump-starting cables and further information regarding jump starting can be obtained at
any qualified specialist workshop. Towing away and tow-starting
Important safety notes
G
WARNING
Safety relevant functions are restricted or no
longer available if:
R the engine is not running
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 away or towed
started, 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
being towed away or tow started, 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. 344
Towing away and tow-startingBreakdown assistance

Details on the permissible gross vehicle
weight of your vehicle can be found on the
vehicle identification plate (Y page 386).
! When COLLISION PREVENTION ASSIST
PLUS, DISTRONIC PLUS or the HOLD func- tion is activated, the vehicle brakes auto-
matically in certain situations. To avoid
damage to the vehicle, deactivate these
systems in the following or similar situa-
tions:
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.
! Only secure the tow cable or tow bar to
the towing eyes or, if available, to the trailer
tow hitch. You could otherwise damage the
vehicle.
! 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 will make other road
users aware that a vehicle is being
towed.
R Only secure the tow cable to the towing
eyes or, if available, to the trailer tow
hitch.
R Observe the brake lamps of the towing
vehicle while driving. Always maintain a
distance a distance so that the tow rope does not sag.
R Do not use steel cables or chains to tow
your vehicle. You could otherwise dam-
age the vehicle.
! Do not use the towing eyes for recovery
purposes as this could damage the vehicle.
If in doubt, recover the vehicle with a crane. !
Pull away smoothly when towing away or
tow-starting a vehicle. 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 frontaxle or the entire vehicle must be raised
and transported.
! To tow vehicles with KEYLESS-GO, use
the key instead of the Start/Stop button.
The automatic transmission may otherwise switch to position Pwhen you open the
driver's or front-passenger door which
could damage the transmission.
! Vehicles with automatic transmission
must not be tow-started. The transmission
may otherwise be damaged.
Observe the legal requirements for the rele-
vant countries when towing and tow-starting.
It is better to have the vehicle transported
than to have it towed.
If the vehicle can no longer be driven because
of an accident or breakdown, you have the
following options:
R Transporting the vehicle.
As a rule, you should have the vehicle trans-
ported.
R Towing the vehicle with a tow rope or tow
bar.
Only tow the vehicle in exceptional cases.
Vehicles with automatic transmission:
when towing a vehicle, the transmission must be in position N.
The battery must be connected and charged.
Otherwise, you:
R cannot turn the key to position 2in the
ignition lock
R cannot release the electric parking brake
R cannot shift the transmission to position N
on vehicles with automatic transmis-
sion Towing away and tow-starting
345Breakdown assistance Z