2014 MERCEDES-BENZ B-CLASS HATCHBACK battery

Problem
Possible causes/consequences and
M
MSolutions There is a fault with KEYLESS-GO.
X Lock/unlock the vehicle using the remote control function of
the key.
X Have the vehicle and key checked at a qualified specialist work-
shop.
If the vehicle can also not be locked/unlocked using the remote
control function:
X Unlock (Y page 95) or lock (Y page 96) the vehicle using the
emergency key element.
X Have the vehicle and key checked at a qualified specialist work-
shop. The engine cannot be
started using the key. The on-board voltage is too low
X Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 341).
or
X Jump-start the vehicle (Y page 342).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The key is
in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The key battery is discharged or nearly discharged.
X Check the key battery (Y page 90) and replace if necessary
(Y page 90).
If this does not work: X Start your vehicle with the key in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the key in the ignition lock. 92
KeyOpening and closing

The system automatically switches from level
3 to level 2after approximately eight
minutes.
The system automatically switches from level 2 to level 1after approximately ten minutes.
The system automatically switches off
approximately 20 minutes after it is set to
level 1.
X Turn the key to position 1or 2in the ignition
lock (Y page 159).
X To switch on: press button:repeatedly
until the desired heating level is set.
X To switch off: press button:repeatedly
until all the indicator lamps go out.
i If the battery voltage is too low, the seat
heating may switch off. Seats
113Seats, steering wheel and mirrors Z

Problems with the seat heating
Problem
Possible causes/consequences and
M
MSolutions The seat heating has
switched off prema-
turely or cannot be
switched on. The on-board voltage is too low because too many electrical con-
sumers are switched on.
X Switch off electrical consumers that you do not need, such as
the rear window heating or interior lighting.
Once the battery is sufficiently charged, the seat heating will
switch back on automatically. Steering wheel
Important safety notes
G
WARNING
You could lose control of the vehicle while
driving if you:
R adjust the driver's seat, steering wheel or
mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirrors and fasten your seat
belt before starting the engine. G
WARNING
Children could become trapped by the steer-
ing wheel if they adjust it. There is a risk of
injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children unattended in the vehicle. Adjusting the steering wheel
G
WARNING
The steering wheel may move unexpectedly if you adjust it while driving. This could cause
you to lose control of the vehicle. There is a
risk of an accident.
Make sure that the steering wheel is locked
before driving off. Never unlock the steering
wheel when the vehicle is in motion. :
Release lever
; To adjust the steering wheel height
= To adjust the steering wheel position
(fore-and-aft adjustment)
X Push release lever :down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired
position.
X Push release lever :up completely.
The steering column is locked.
X Check if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction. 114
Steering wheelSeats, steering wheel and mirrors

Folding the exterior mirrors in/out elec-
trically X
Turn the key to position 1or 2in the ignition
lock (Y page 159).
X Briefly press button :.
Both exterior mirrors fold in or out.
i Make sure that the exterior mirrors are
always folded out fully while driving. They
could otherwise vibrate.
i If you are driving faster than 47 km/h, you
can no longer fold in the exterior mirrors.
Resetting the exterior mirrors If the battery has been disconnected or com-
pletely discharged, the exterior mirrors must
be reset. The exterior mirrors will otherwise
not fold in when you select the "Fold in mir-
rors when locking" function in the on-board
computer (Y page 249).
X Turn the key to position 1in the ignition
lock (Y page 159).
X Briefly press button :.
Folding the exterior mirrors in/out
automatically If the "Fold in mirrors when locking" function
is activated in the on-board computer
(Y page 249): R
the exterior mirrors fold in automatically as
soon as you lock the vehicle from the out-
side
R the exterior mirrors fold out again automat-
ically as soon as you unlock the vehicle and
then open the driver's or front-passenger
door
i If the exterior mirrors have been folded in
manually, they do not fold out.
Exterior mirror pushed out of position If an exterior mirror has been pushed out of
position (forwards or backwards), proceed as
follows:
X Vehicles without electrically folding
exterior mirrors: manually move the exte-
rior mirror into the correct position.
X Vehicles with electrically folding exte-
rior mirrors: press and hold mirror-folding
button (Y page 116) until you hear a click
and the mirror engages in position audibly.
The mirror housing is engaged again and
you can adjust the exterior mirrors as usual
(Y page 115). Automatic anti-dazzle mirrors
G
WARNING
Electrolyte may escape if the glass of an auto- matic anti-dazzle mirror breaks. Electrolyte is
harmful and causes irritation. It must not
come into contact with your skin, eyes, res-
piratory organs or clothing or be swallowed.
There is a risk of injury.
If you come into contact with electrolyte,
observe the following:
R immediately rinse off electrolyte from your
skin with water.
R immediately and thoroughly rinse electro-
lyte out of eyes using clean water.
R if electrolyte is swallowed, immediately
rinse out your mouth thoroughly. Do not
induce vomiting. 116
MirrorsSeats, steering wheel and
mirrors

X
Press the Rbutton.
The yellow Rindicator lamp in the
instrument cluster lights up.
X To switch off the rear foglamp: press the
R button.
The yellow Rindicator lamp in the
instrument cluster goes out.
Side lamps ! If the battery has been excessively dis-
charged, the side lamps or parking lamps
are automatically switched off to enable
the next engine start. Always park your
vehicle safely and sufficiently lit according
to legal standards. Avoid the continuous
use of the Tside lamps for several
hours. If possible, switch on the Xright
or the Wleft parking lamp.
X To switch on: turn the light switch to T.
The green Tindicator lamp in the instru-
ment cluster lights up.
Parking lamps
Switching on the parking lamps ensures that
the corresponding side of the vehicle is illu-
minated.
X To switch on the parking lamps: the key
is not in the ignition lock or it is in posi-
tion 0.
X Turn the light switch to W(left-hand side
of the vehicle) or X(right-hand side of
the vehicle). Adjusting the headlamp range (halogen
headlamps) g
Driver's seat and front-passenger seat
occupied
1 Driver's seat, front-passenger seat and
rear seats occupied
2 Driver's seat, front-passenger seat and
rear seats occupied, luggage compart-
ment laden
3 Driver's and front-passenger seats occu-
pied and maximum permissible rear axle
load utilised, e.g. when towing a trailer
The headlamp range control allows you to
adjust the cone of light from the headlamps to suit the vehicle load.
X Start the engine.
X Turn the headlamp range control to the
position which corresponds to the load in
your vehicle. 124
Exterior lightingLights and windscreen wipers

indicator lamp in the multifunction display
remains lit.
X To deactivate: move the combination
switch back to its normal position.
The _ indicator lamp in the multifunc-
tion display goes out. Headlamps misted up on the inside
Certain climatic and physical conditions may
cause moisture to form in the headlamp. This
moisture does not affect the functionality of
the headlamp. Interior lighting
Overview of interior lighting
Front overhead control panel :
p Switches the left-hand front reading
lamp on/off
; c Switches the front interior lighting
on
= v Switches the rear interior lighting
on/off
? | Switches the front interior lighting/
automatic interior lighting control off
A p Switches the right-hand front read-
ing lamp on/off
B Switches the automatic interior lighting
control on Control panel in the grab handle in the
rear compartment
:
Switches the reading lamp on/off Interior lighting control
General notes In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time,
unless the key is in position 2in the ignition
lock.
The colour and brightness for the ambient
lighting may be set using COMAND Online or
Audio 20 (see the separate operating instruc-
tions).
Automatic interior lighting control X
To switch on: set the switch to centre
position B.
X To switch off: set the switch to the |
position.
The interior lighting automatically switches
on if you:
R unlock the vehicle
R open a door
R remove the key from the ignition lock
The interior lighting is activated for a short
time when the key is removed from the igni-
tion lock. This delayed switch-off can be
adjusted using COMAND Online or Audio 20
(see the separate operating instructions). Interior lighting
127Lights and windscreen wipers Z

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