2012 MERCEDES-BENZ B-CLASS ignition

Activating/deactivating surround
lighting and exterior lighting delayed
switch-off
If you have activated the
Locator
Lighting: function
and
the light switch is set
to Ã, the following functions are activated
when it is dark:
R surround lighting: the exterior lighting
remains lit for 40 seconds after unlocking
with the SmartKey. If you start the engine,
the surround lighting is switched off and
automatic headlamp mode is activated
(Y page 99).
R exterior lighting delayed switch-off: the
exterior lighting remains lit for
60 seconds after the engine is switched off.
If you close all the doors and the trunk lid,
the exterior lighting goes off after
15 seconds.
X Press the = or ; button on the
steering wheel to select the Sett. menu.
X Press the :
or 9
button to select the
Lights submenu.
X Press a to confirm.
X Press the : or 9
button to select the
Locator Lighting function.
You will see the selected setting: Enabled
or Disabled.
X Press the a button to save the setting.
Deactivating delayed switch-off of the
exterior lighting temporarily:
X Before leaving the vehicle, turn the
SmartKey to position 0

in the ignition lock.
X Turn the SmartKey to position 2 in the
ignition lock.
The exterior lighting delayed switch-off is
deactivated.
Delayed switch-off of the exterior lighting is
reactivated the next time you start the
engine.
i Depending on your vehicle's equipment,
when the surround lighting and delayed
switch-off exterior lighting are on, the
following light up: R
Parking lamps
R Front fog lamps
R Low-beam headlamps
R Daytime running lamps
R Side marker lamps
R Surround lighting in the exterior mirrors
Activating/deactivating the interior
lighting delayed switch-off
If you activate the Interior Lighting
Delay function, the interior lighting remains
on for 20seconds after you remove the
SmartKey from the ignition lock.
X Press the = or ; button on the
steering wheel to select the Sett. menu.
X Press the : or 9
button to select the
Lights submenu.
X Press a to confirm.
X Press the :
or 9

button to select the
Interior Lighting Delay function.
You will see the selected setting: Enabled
or Disabled.
X Press the a button to save the setting.
Vehicle Activating/deactivating the automatic
door locking mechanism
X
Press the = or ; button on the
steering wheel to select the Sett menu.
X Press the :
or 9
button to select the
Vehicle submenu.
X Press a to confirm.
X Press the :
or 9

button to select the
Automatic Door Lock function.
You will see the selected setting: Enabled
or Disabled.
X Press the a button to save the setting.
If you select the Automatic Door Lock
function, the
vehicle

is centrally locked above
a speed of around 9 mph (15 km/h).
i For further information on the automatic
locking feature, see ( Y page 74).198
Menus and submenus
On-board computer and displays
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Display messages
General notes
Display messages appear in the multifunction display.
Display messages with graphic displays may be shown in simplified form in the Operator's
Manual and may differ from the messages shown in the multifunction display.
Please respond in accordance with the display messages and follow the additional notes in
this Operator's Manual.
Certain display messages
are accompanied by an audible warning tone or a continuous tone.
When the ignition is switched off, all display messages are deleted, apart from some high-
priority display messages. Once the causes of the high-priority display messages have been
rectified, the corresponding display messages are also deleted.
When you stop and park the vehicle, please observe the notes on the HOLD function
(Y page 167) and parking ( Y page 149).Hiding display messages
X Press the a or % button on the steering wheel to hide the display message.
The display message is cleared.
The multifunction display shows high-priority display messages in red. Some high-priority
display messages cannot be hidden.
The multifunction display shows these messages continuously until the causes for the
messages have been remedied. Message memory
The on-board computer saves certain display messages in the message memory. You can
call up the display messages:
X Press = or ; on the steering wheel to select the Serv menu.
If there are display messages, the multifunction display shows, for example, 2 Messages.
X Press the 9 or : button to select the entry, e.g. 2 Messages.
X Press a to confirm.
X Press the 9 or : button to scroll through the display messages.200
Display messages
On-board computer and displays
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Display messages Possible causes/consequences and
M SolutionsPlease Release
Parking Brake
The red
F (USA only)/! (Canada only) indicator lamp
flashes and a warning tone sounds.
You are using the electric parking brake for emergency braking
(Y page 150). F(USA
only)!(Canada
only)
Parking Brake See
Operator's Manual The yellow
! warning lamp lights up.
The electric parking brake is malfunctioning.
To apply:
X Switch the ignition off.
X Press the electric parking brake handle for at least ten seconds.
X Shift the transmission to P.
X Consult a qualified specialist workshop. The yellow
! warning lamp and the red F (USA
only)/! (Canada only) indicator lamp light up.
The electric parking brake is malfunctioning.
To release:
X Switch off the ignition and turn it back on.
X Release the electric parking brake manually.
or
X Release the electric parking brake automatically ( Y page 150).
If the electric parking brake still cannot be released:
X Do not drive on.
X Consult a qualified specialist workshop.204
Display messagesOn-board computer and displays
ProCarManuals.com

Display messages Possible causes/consequences and
M SolutionsThe red
F (USA only)/! (Canada only) indicator lamp
flashes and the yellow ! warning lamp lights up.
The electric parking brake is malfunctioning.
To release:
X Switch off the ignition and turn it back on.
X Release the electric parking brake manually.
To apply:
X Switch off the ignition and turn it back on.
X Apply the electric parking brake manually.
If the red F (USA only)/! (Canada only) indicator lamp
continues to flash:
X Do not drive on.
X Secure the vehicle against rolling away ( Y page 320).
X Shift the transmission to P.
X Turn the front wheels towards the curb.
X Consult a qualified specialist workshop. The yellow
! warning lamp lights up. The red F (USA
only)/! (Canada only) indicator lamp flashes for about ten
seconds after the electric parking brake has been applied or
released. It then goes out or remains lit.
The electric parking brake is malfunctioning.
X Switch off the ignition and turn it back on.
X Apply the electric parking brake.
If it is not possible to engage the electric parking brake:
X Shift the transmission to P.
X Visit a qualified specialist workshop.
If it is not possible to release the electric parking brake:
X Release the electric parking brake automatically ( Y page 150).
If the electric parking brake still cannot be released:
X Consult a qualified specialist workshop. Display messages
205On-board computer and displays Z
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Display messages Possible causes/consequences and
M SolutionsThe yellow
! warning lamp lights up. If you manually apply or
release the electric parking brake, the red F (USA
only)/! (Canada only) indicator lamp flashes.
The electric parking brake is malfunctioning. It is not possible to
apply the electric parking brake manually.
X Shift the transmission to P.
X Visit a qualified specialist workshop. F(USA
only)!(Canada
only)
Parking Brake
Inoperative The yellow
! warning lamp lights up. The red F (USA
only)/! (Canada only) indicator lamp flashes for about ten
seconds after the electric parking brake has been applied or
released. It then goes out or remains lit.
The electric parking brake is malfunctioning, e.g. because of
overvoltage or undervoltage.
X Remove the cause for the overvoltage or undervoltage, e.g. by
charging the battery or restarting the engine.
X Engage or release the electric parking brake.
If it remains impossible to apply or release the electric parking
brake:
X Switch off the ignition and turn it back on.
X Engage or release the electric parking brake.
If the electric parking brake still cannot be released:
X Consult a qualified specialist workshop. The display message is only shown while the vehicle is in motion.
The yellow
! warning lamp lights up and the red F (USA
only)/ ! (Canada only) indicator lamp flashes.
It is not possible to apply the electric parking brake manually.
X Shift the transmission to P.
X Visit a qualified specialist workshop. F(USA
only)!(Canada
only)
Turn On the
Ignition to
Release the
Parking Brake The red
F (USA
only)/ ! (Canada only) indicator lamp lights
up.
You attempted to release the electric parking brake while the
ignition was switched off.
X Turn the SmartKey to position 1 in the ignition lock.206
Display messages
On-board computer and displays
ProCarManuals.com

Display messages Possible causes/consequences and
M Solutions¥
Check Washer Fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
i
If you do
not mix antifreeze with the washer fluid in the winter
months, then the washer fluid could freeze in the washer fluid
reservoir. In this case the Check Washer Fluid display
message could also be shown in the multifunction display.
X Add washer fluid ( Y page 269).Wiper
Malfunctioning The windshield wipers are malfunctioning.
X
Visit a qualified specialist workshop. Hazard Warning
Flashers
Malfunctioning The hazard warning lamps are faulty.
X
Visit a qualified specialist workshop. SmartKey
Display messages Possible causes/consequences and
M Solutions+
Key Does Not
Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X
Use the correct SmartKey. +
Take Your
Key

from
Ignition The SmartKey is in the ignition lock.
X
Remove the SmartKey. +
Obtain a New Key The SmartKey needs to be replaced.
X
Visit a qualified specialist workshop. Display messages
223
On-board computer and displays Z
ProCarManuals.com

Engine
Problem Possible causes/consequences and
M Solutions;
The yellow Check
Engine warning lamp
lights up while the
engine is running.
There may be a malfunction, for example:
R
in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified
specialist workshop as
soon as the yellow Check Engine warning
lamp lights up. This depends on the locally applicable legal
requirements. If in doubt, check whether such legal regulations
apply in the state in which you are currently driving. æ
The yellow reserve fuel
warning lamp lights up
while the engine is
running.
The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station. æ
The yellow reserve fuel
warning lamp flashes
while the engine is
running.
The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X
Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed:
close the

fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist
workshop. ?
The red coolant
warning lamp lights up
while the engine is
running and
the

coolant
temperature gage is at
the start of the scale. The temperature sensor for the coolant temperature gage is
defective.
The coolant
temperature
is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to

road and traffic conditions. Do not continue
driving under any circumstances.
X Secure the vehicle against rolling away ( Y page 149).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
231
On-board computer and displays Z
ProCarManuals.com

i
If you remove the ashtray insert, you can
use the resulting compartment for
stowage.
Rear-compartment ashtray X
To open: pull cover = out by its top edge.
X To remove: pull insert ; by recess : in
the direction of arrow ? until it audibly
releases.
X Lift insert ; up and out.
X To install the insert: place
insert ;
from
above into the holder and press down until
it engages. Cigarette lighter
G
WARNING
You can burn yourself if you touch the hot
heating element or

the socket of the cigarette
lighter.
In addition, flammable materials can ignite if:
R the hot cigarette lighter falls
R a child holds the hot cigarette lighter to
objects, for example
There is a risk of fire and injury.
Always hold the cigarette lighter by the knob.
Always make sure that the cigarette lighter is
out of reach of children. Never leave children
unsupervised in the vehicle.
Your attention must always be focused on the
traffic conditions. Only use the cigarette lighter when road and traffic conditions
permit.
Example: vehicles with a cover over the stowage
compartment
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To open: push the lower section of
cover :.
The stowage compartment opens.
X Press in cigarette lighter ;.
Cigarette lighter ; will pop out
automatically when the heating element is
red-hot. 12 V sockets
Points to observe before use X
Turn the SmartKey to position 1 in the
ignition lock (Y page 135).
The sockets can be used for accessories with
a maximum draw of 180 W (15 A).
Accessories include such items as lamps or
chargers for mobile phones.
If you use the sockets for long periods when
the engine is switched off, the battery may
discharge.
i An emergency cut-out ensures that the
on-board voltage does not drop too low. If
the on-board voltage is too low, the power
to the sockets is automatically cut. This
ensures that there is sufficient power to
start the engine. 250
Features
Stowage and features
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