key MERCEDES-BENZ B-CLASS HATCHBACK 2014 Repair Manual

THERMOTRONIC automatic climate con-
trol
X Activate the ¿"Cooling with air dehu-
midification" function.
X Activate automatic mode Ã.
X If the windows continue to mist up, activate
the ¬ "Windscreen demisting" function.
i You should only select this setting until
the windscreen is clear again.
Windows misted up on the outside X
Activate the windscreen wipers.
X Set the air distribution to PorO.
i You should only select this setting until
the windscreen is clear again. Rear window heating
General notes The rear window heating has a high current
draw. You should therefore switch it off as
soon as the window is clear. It otherwise
switches off automatically after several
minutes.
If the battery voltage is too low, the rear win-
dow heating may switch off.
Switching on/off X
Turn the key to position 2in the ignition
lock (Y page 159).
X Press the ¤button.
The indicator lamp in the ¤button lights
up or goes out. Operating the climate control system
147Climate control

Problems with the rear window heating
Problem
Possible causes/consequences and
M
MSolutions The rear window heat-
ing has switched off
prematurely or cannot
be activated. The battery has not been sufficiently charged.
X Switch off any consumers that are not required, e.g. reading
lamps, interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window heat- ing can be activated again. Activating/deactivating air-recircula-
tion mode
General notes You can deactivate the flow of fresh air if
unpleasant odours are entering the vehicle
from outside. The air already inside the vehi-
cle will then be recirculated.
If you activate air-recirculation mode, the win-
dows can mist up more quickly, in particular
at low temperatures. Only use air-recircula-
tion mode briefly to prevent the windows
misting up.
The operation of air-recirculation mode is the same for all control panels.
Switching on/off X
Turn the key to position 2in the ignition
lock (Y page 159).
X To activate: press theebutton.
The indicator lamp in the ebutton lights
up.
Air-recirculation mode is activated automati-
cally:
R at high outside temperatures
R at high levels of pollution
When air-recirculation mode is activated
automatically, the indicator lamp in the e
button is not lit. Outside air is added after
about 30 minutes.
X To deactivate: press theebutton.
The indicator lamp in the ebutton goes
out. i
Air-recirculation mode is deactivated
automatically:
R after approximately five minutes at out-
side temperatures below approximately
7 †
R after approximately five minutes if the
"Cooling with air dehumidification" func-
tion is deactivated
R after approximately 30 minutes at out-
side temperatures above approximately
7 † if the cooling with air dehumidifica-
tion function is activated Convenience opening/closing using
the air-recirculation button
G
WARNING
When the convenience closing feature is oper- ating, parts of the body could become trapped
in the closing area of the side window and the
sliding sunroof. There is a risk of injury.
Observe the complete closing procedure
when the convenience closing feature is oper-
ating. When closing make sure that no parts of the body are in the closing area. G
WARNING
During convenience opening parts of the body could be drawn in or become trapped
between the side window and window frame.
There is a risk of injury.
When opening, make sure that nobody is
touching the side window. If someone
becomes trapped, press the Wswitch 148
Operating the climate control systemClimate control

Switching on/off
X
Turn the key to position 0in the ignition
lock or remove it (Y page 159).
X To activate: press theÃŒbutton.
The indicator lamp in the ÃŒbutton lights
up.
X To deactivate: press theÃŒbutton.
The indicator lamp in the ÃŒbutton goes
out.
i Residual heat is deactivated automati-
cally:
R after approximately 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R when the auxiliary heating is switched on Auxiliary heating
Important safety notes G
DANGER
If the exhaust pipe is blocked or sufficient
ventilation is not possible, toxic exhaust
fumes can enter the vehicle, especially car-
bon monoxide. This is the case, e.g. in
enclosed spaces, or if the vehicle is stuck in
snow. There is a risk of fatal injuries.
You should switch off the auxiliary heating in
enclosed spaces which do not have an extrac- tion system, e.g. a garage. If the vehicle is
stuck in snow and you must leave the auxiliary
heating running, keep the exhaust pipe and
the area around the vehicle clear of snow. To guarantee a sufficient supply of fresh air, open
a window on the side of the vehicle away from the wind. G
WARNING
When the auxiliary heating is switched on,
parts of the vehicle can become very hot. Flammable materials such as leaves, grass or
twigs may ignite if they come into contact
with:
R hot parts of the exhaust system
R the exhaust gas itself
There is a risk of fire.
When the auxiliary heating is switched on,
make sure that:
R no flammable materials come into contact
with hot vehicle components
R the exhaust gas can escape from the
exhaust pipe unhindered
R the exhaust gas does not come into contact
with flammable materials.
The auxiliary heating and the exhaust gas out-
let are situated in front of the right-hand front
wheel.
! Operating the auxiliary heating/ventila-
tion draws on the vehicle battery. After you
have heated or ventilated the vehicle a
maximum of two times, drive for a longer
distance.
Switch the auxiliary heating on regularly once
a month for about ten minutes.
The auxiliary heating heats the air in the vehi- cle interior to the set temperature. This
occurs without using the heat of the running
engine. The auxiliary heating is operated
directly using the vehicle's fuel. For this rea-
son, the fuel tank must be at least Õfull to
ensure that the auxiliary heating functions.
The auxiliary heating/ventilation automati-
cally adjusts to changes in temperature and
weather conditions. For this reason, the aux-
iliary heating could switch from ventilation
mode to heating mode or from heating mode to ventilation mode.
The auxiliary heating switches off when the
engine is switched off. The auxiliary ventila-
tion switches off when you turn the key to key
position 2(Y page 159).
The auxiliary heating switches off automati-
cally after 30 minutes. 150
Operating the climate control systemClimate control

You cannot use the auxiliary ventilation to
cool the vehicle interior to a temperature
lower than the outside temperature.
Before switching on X
Turn the key to position 2in the ignition
lock (Y page 159).
X Set the desired temperature.
Auxiliary heating or ventilation can also be
switched on if the manually set climate con-
trol is activated. Optimum comfort is attained by setting the system to automatic mode. Set
the temperature to 22 †.
The auxiliary heating/ventilation can be acti- vated or deactivated using the remote control or the button on the centre console.
The on-board computer can be used to spec-
ify up to three departure times, one of which
may be preselected (Y page 248).
Switching the auxiliary heating/venti-
lation on/off using the centre console
button General notes
The colours of the indicator lamps in but-
ton :mean the following:
R Blue: auxiliary ventilation is switched on
R Red: auxiliary heating is activated
R Yellow: departure time is preselected
(Y page 248) Switching on the auxiliary heating/venti-
lation
X Press button :.
The red or blue indicator lamp in button :
lights up.
Switching off the auxiliary heating/venti- lation
X Press button :.
The red or blue indicator lamp in button :
goes out.
Switching the auxiliary heating/venti-
lation on/off using the remote control General notes
Your vehicle comes with one remote control.
You may use two additional remote controls
for your vehicle. For more information, please contact a qualified specialist workshop.
Store the remote control for the auxiliary
heating so that the auxiliary heating cannot
be switched on unintentionally. In particular,
ensure that the remote control for the auxili-
ary heating is kept out of the reach of chil-
dren.
The remote control has a range of approx-
imately 300 metres. This range is reduced by:
R sources of radio interference
R solid objects between the remote control
and the vehicle
R the remote control being in an unfavoura-
ble position in relation to the vehicle
R transmitting from an enclosed space
If the remote control battery is low, the bat-
tery symbol on the left of the display is shown as empty. Replace the remote control battery and observe the important safety notes when
doing so (Y page 153). Operating the climate control system
151Climate control Z

boosting effect. You will require considerably
more effort to steer and brake. There is a riskof an accident.
Do not switch off the ignition while driving. G
WARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine when the vehi-
cle is stationary. Drive off immediately.
Avoid high engine speeds and driving at full throttle until the engine has reached its
operating temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train. Key positions
Key g
To remove the key
1 Power supply for some consumers, such
as the windscreen wipers 2
Ignition (power supply for all consumers)
and drive position
3 To start the vehicle
Vehicles with manual transmission: the
steering is locked when the key is taken out of the ignition lock.
i If the key does not belong to the vehicle, it
can still be turned in the ignition lock. How- ever, the ignition will not be switched on.
The engine cannot be started.
Start/Stop button General notes
Vehicles with KEYLESS-GO are equipped with
keys featuring an integrated KEYLESS-GO
function and a detachable Start/Stop button.
A check which periodically establishes a radio connection between the vehicle and the key
determines whether a valid key is in the vehi-
cle. This occurs, for example, when starting
the engine.
When you insert the Start/Stop button into
the ignition lock, the system needs approx-
imately two seconds recognition time. You
can then use the Start/Stop button.
Pressing the Start/Stop button several times
in succession corresponds to the different
key positions in the ignition lock. Pre-requi-
site for this is that:
R you do not depress the brake pedal (vehi-
cles with automatic transmission)
R you do not depress the clutch pedal (vehi-
cles with manual transmission)
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi- ately (vehicles with automatic transmission).
If you depress the clutch pedal and press theStart/Stop button, the engine starts immedi-
ately (vehicles with manual transmission). Driving
159Driving and parking Z

To start the vehicle without actively using the
key:
R the Start/Stop button must be inserted in
the ignition lock
R the key must be in the vehicle
R the vehicle must not be locked with the key
or KEYLESS-GO (Y page 87)
Do not keep the KEYLESS-GO key:
R with electronic devices, e.g. a mobile
phone or another key
R with metallic objects, e.g. coins or metal
film
R inside metallic objects, e.g. a metal case
This can affect the functionality of KEYLESS-
GO.
If you lock the vehicle with the key's remote
control or with KEYLESS-GO, after a short
time:
R you will not be able to switch on the ignition
with the Start/Stop button
R you will not be able to start the engine with
the Start/Stop button until the vehicle is
unlocked again
If you lock the vehicle centrally using the but-
ton on the front door (Y page 94), you can
continue to start the engine with the Start/
Stop button.
The engine can be switched off while the vehi-
cle is in motion by pressing and holding the
Start/Stop button for three seconds. This
function operates independently of the ECO
start/stop automatic engine switch-off func-
tion. Key positions with the Start/Stop button :
Start/Stop button
; Ignition lock
When you switch on the ignition, all of the
indicator lamps in the instrument cluster light up. Further information on situations where
an indicator lamp either fails to go out after
starting the engine or lights up while driving
(Y page 286).
If Start/Stop button :has not yet been
pressed, this corresponds to the key being
removed from the ignition.
X To switch on the power supply: press
Start/Stop button :once.
The power supply is switched on. You can
now activate the windscreen wipers, for
example.
The power supply is switched off again if:
R the driver's door is opened and
R you press Start/Stop button :twice when
in this position
X To switch on the ignition: press Start/
Stop button :twice.
The ignition is switched on.
The ignition is switched off if:
R the driver's door is opened and
R you press Start/Stop button :twice when
in this position
Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the key. 160
DrivingDriving and parking

You can only switch between Start/Stop but-
ton mode and key operation when the vehicle is stationary.
You must also engage park position P(vehi-
cles with automatic transmission).
X Remove Start/Stop button :from ignition
lock ;.
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take the key with you when leaving the vehicle. As long as the key is in the vehicle:
R the vehicle can be started using the Start/
Stop button
R the electrically powered equipment can be
operated Starting the vehicle
Important safety notes G
WARNING
If children are left unsupervised in the vehicle, they could:
R open doors, thereby endangering other per-
sons or road users
R get out and be struck by oncoming traffic
R operate vehicle equipment and become
trapped, for example
In addition, the children could also set the
vehicle in motion, for example, if they:
R release the parking brake
R shift the automatic transmission out of park
position P or shift manual transmission into
neutral
R start the engine
There is a risk of an accident and injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children and animals unattended in the vehi-
cle. Keep the keys out of the reach of children. G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation. G
WARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
! Do not depress the accelerator when
starting the engine.
General notes Vehicles with a petrol engine:
the engine
runs at a higher engine speed during the cold
start procedure so that the catalytic con-
verter can reach operating temperature more quickly. The sound of the engine may change
as a result.
Manual transmission You can only start the engine when the clutch
pedal is fully depressed.
X Depress the brake pedal and keep it
depressed.
X Depress the clutch pedal fully.
X Shift to neutral N.
Automatic transmission X
Shift the transmission to position P
(Y page 170).
The transmission position indicator in the
multifunction display shows P
(Y page 170). Driving
161Driving and parking Z

When the transmission is in position
N, you
can also start the engine with the brake pedal
depressed.
Starting procedure with the key To start the engine using the key instead of
the Start/Stop button, pull the Start/Stop
button out of the ignition lock.
X To start a petrol engine: turn the key to
position 3in the ignition lock (Y page 159)
and release it as soon as the engine is run-
ning.
X To start a diesel engine: turn the key to
position 2in the ignition lock (Y page 159).
The % preglow indicator lamp in the
instrument cluster lights up.
X When the %preglow indicator lamp
goes out, turn the key to position 3
(Y page 159) and release it as soon as the
engine is running.
You can start the engine without preglow if
the engine is warm.
Starting procedure using the Start/
Stop button The Start/Stop button can be used to start
the vehicle manually without inserting the key into the ignition lock. The key must be in the
vehicle and the Start/Stop button must be
inserted in the ignition lock. This mode for
starting the engine operates independently of
the ECO start/stop automatic engine start
function.
You can start the engine if a valid key is in the vehicle. Switch off the engine and always take
the key with you when leaving the vehicle,
even if you only leave it for a short time. Pay
attention to the important safety notes.
X Vehicles with automatic transmission:
depress the brake pedal and keep it
depressed.
X Vehicles with manual transmission:
depress the clutch pedal and keep it
depressed. X
To start a petrol engine: press the Start/
Stop button once (Y page 159).
The engine starts.
X To start a diesel engine: press the Start/
Stop button once (Y page 159).
Preglow is activated and the engine starts. Pulling away
Manual transmission !
Change gear in good time and avoid spin-
ning the wheels. Otherwise, you could dam- age the vehicle.
Depress the accelerator carefully when pull-
ing away.
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 lockingfeature (Y page 247).
Automatic transmission G
WARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
Depress the accelerator carefully when pull-
ing away.
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 247). 162
DrivingDriving and parking

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 :
ECO start/stop display (example: colour
multifunction display)
The ECO start/stop function automatically
switches the engine off when the vehicle
stops moving if:
R the è ECO symbol appears in the mul-
tifunction display in vehicles with black and white multifunction display.
R the è ECO symbol appears in green in
the multifunction display in vehicles with a
colour multifunction display.
The stop/start function is automatically acti-
vated each time you start the engine with the ignition key.
If the ECO start/stop function has been man- ually deactivated (Y page 166) or a malfunc-
tion has caused the system to be deactivated, the è ECO symbol is not displayed. Automatic engine switch-off General notes
The ECO stop/start function is operational
and shows the following in the multifunction
display:
R the è ECO symbol in vehicles with a
black-and-white multifunction display
R a green èECO symbol in vehicles with a
colour multifunction display
This is the case if, among other things:
R the indicator lamp in the ECO button is lit
green
R the outside temperature is within the range
that is suitable for the system
R the engine is at normal operating temper-
ature
R the set temperature for the vehicle interior
has been reached
R the battery is sufficiently charged
R the system detects that the windscreen is
not misted up when the air-conditioning
system is switched on
R the bonnet is closed
R the driver's door is closed and the driver's
seat belt is fastened
If not all conditions for an automatic engine
switch-off are met:
R the è ECO symbol does not appear in
vehicles with a black-and-white multifunc-
tion display.
R a yellow èECO symbol appears in vehi-
cles with a colour multifunction display.
All of the vehicle's systems remain active
when the engine is switched off automati-
cally.
The engine can be switched off automatically
a maximum of four times (initial stop, then
three subsequent stops) in succession.
On vehicles with a black-and-white multifunc- tion display, the automatic engine switch-off
is then available again after the ECO symbol
appears in the multifunction display. 164
DrivingDriving and pa
rking

Problems with the engine
Problem
Possible causes/consequences and
M
MSolutions The engine does not
start. The HOLD function or DISTRONIC PLUS is activated.
X Deactivate the HOLD function (Y page 201) or DISTRONIC
PLUS (Y page 193).
X Try to start the engine again. The engine does not
start. The starter motor
can be heard. R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
Before attempting to start the engine again:
X Turn the key to position 0in the ignition lock.
or
X Press the Start/Stop button repeatedly until all indicator lamps
in the instrument cluster go out.
X Try to start the engine again (Y page 161). Avoid excessively
long and frequent attempts to start the engine, as this will drain the battery.
If the engine does not start after several attempts: X Consult a qualified specialist workshop. The engine does not
start. The starter motor
can be heard. The
reserve fuel warning
lamp is lit and the fuel
gauge display shows 0. The fuel tank is empty.
X Refuel the vehicle. The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak or
discharged.
X Jump-start the vehicle (Y page 342).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to a thermal load that was too high.
X Allow the starter motor to cool down for approximately two
minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop, e.g. a Mercedes-Benz
Service Centre. Driving
167Driving and parking Z