ignition MERCEDES-BENZ B-CLASS 2012 Repair Manual

!
A display message
is shown if the coolant
temperature is too high.
If the coolant temperature is over
248 ‡(120 †), do not continue driving. The
engine will otherwise be damaged.
The coolant temperature gage is in the
instrument cluster on the right-hand side.
Under normal operating conditions and with
the specified coolant level, the coolant
temperature may rise to 248 ‡ (120 †). Tachometer
! Do not drive in the overrevving range, as
this could damage the engine.
The red band

in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached. Outside temperature display
You should pay special attention to road
conditions when temperatures are around
freezing point.
The outside temperature display is in the
multifunction display.
Changes in the outside temperature are
displayed after a short delay. Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
R Cruise control activated ( Y page 157):
The segments light up from the stored
speed to the maximum speed.
R DISTRONIC PLUS activated (Y page 159):
One or two segments in the set speed
range light up.
R DISTRONIC PLUS detects

a vehicle in front:The segments between the speed of the
vehicle in front and the stored speed light
up. Operating the on-board computer
Overview :
Multifunction display
; Switches on the Voice Control System;
see the separate operating instructions
= Right control panel
? Left control panel
A Back button
X To activate the on-board computer: turn
the SmartKey to position 1 in the ignition
lock.
You

can control the multifunction display and
the settings in the on-board computer using
the buttons on the multifunction steering
wheel. Displays and operation
187
On-board computer and displays Z
ProCarManuals.com

The From Start trip computer is
automatically reset when:
R
the ignition has
been switched off for more
than four hours.
R 999 hours have been exceeded.
R 9,999 miles have been exceeded.
If the value exceeds 9,999 hours or
99,999 miles, the From Reset trip computer
is automatically reset.
ECO display Example: ECO display
X
Press the = or ; button on the
steering wheel to select the Trip menu.
X Press 9 or : to select ECO
DISPLAY.
If the ignition remains switched off for longer
than four hours, the ECO display will be
automatically reset.
Further information on the ECO display
(Y page 153).
Displaying the range and current fuel
consumption X
Press the = or ; button on the
steering wheel to select the Trip menu.
X Press the 9 or : button to select
current fuel consumption ; and
approximate range :. Approximate range : is calculated
according to
the
current driving style and the
amount of fuel in the tank. If there is only a
small amount of fuel left in the fuel tank, the
display shows a vehicle being refueled C
instead of range :.
Digital speedometer X
Press the = or ; button on the
steering wheel to select the Trip menu.
X Press the 9 or : button to select
digital speedometer :.
Resetting values Example: resetting the trip computer "From Start"
You can reset the values of the following
functions:
R
Trip odometer
R "From Start" trip computer
R "From Reset" trip computer
R ECO display
X Press the = or ; button on the
steering wheel to select the Trip menu.
X Press the 9 or :
button to select the
function that you wish to reset.
X Press the a button.
X Press the : button to select Yes and
press a to confirm. 190
Menus and submenus
On-board computer and displays
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X
Start the engine.
X Press the = or ; button on the
steering wheel to select the DriveAssist
menu.
X Press the 9 or : button to select
ESP.
X Press the a button.
X To deactivate: press a again.
The å warning lamp in the instrument
cluster lights up.
X To activate: press a again.
The å warning lamp in the instrument
cluster goes out.
Switching the distance warning
function on and off X
Press the = or ; button on the
steering wheel to select the DriveAssist
menu.
X Press 9 or : to select Distance
Warning.
X Press the a button.
The current selection is displayed.
X To activate/deactivate: press the a
button again.
When the distance warning function is
activated, the multifunction display shows
the Ä symbol if the HOLD function is not
activated (Y page 167).
Vehicles with Active Parking Assist: if
PARKTRONIC is activated
and you are driving
at a speed under 22 mph (35 km/h), the j
Active Parking Assist symbol is shown instead
of the Ä symbol ( Y page 172).
Further information on the distance warning
function ( Y page 60). Activating/deactivating ATTENTION
ASSIST X
Press the = or ; button on the
steering wheel to select the DriveAssist
menu.
X Press 9 or : to select Attention
Asst.
X Press the a button.
The current selection is displayed.
X To activate/deactivate: press the a
button again.
When ATTENTION ASSIST (Y page 180) is
activated, the À symbol appears in the
multifunction display when

the ignition is on.
Activating/deactivating Blind Spot
Assist X
Press the = or ; button on the
steering wheel to select the DriveAssist
menu.
X Press 9 or :
to select Blind Spot
Assist.
X Press the a button.
The current selection is displayed.
X To activate/deactivate: press the a
button again.
For further information about Blind Spot
Assist, see (Y page 181).
When the Blind Spot Assist: Sensors
Deactivated message is shown, the radar
sensors are deactivated.
X Switch on the radar sensor system
(Y page 199).
Activating/deactivating Lane Keeping
Assist X
Press the = or ; button on the
steering wheel to select the DriveAssist
menu.
X Press 9 or : on the steering wheel
to select Lane Keep. Asst. Menus and submenus
195
On-board computer and displays Z
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X
Press the a button.
The current selection is displayed.
X Press a to confirm.
X Press the : or 9 button to set Off,
Standard or Adaptive.
X Press the a button to save the setting.
If Lane Keeping Assist is activated
(Y page 183) and
the ignition is switched on,
the à symbol appears in the multifunction
display. Maintenance menu
In the
Serv menu, you have the following
options:
R Calling up display messages in message
memory ( Y page 200)
R Restarting the tire pressure loss warning
system (Y page 305)
R Calling up the service due date
(Y page 270) Settings menu
Introduction In the
Sett menu, you have the following
options:
R changing the instrument cluster settings
R changing the light settings
R changing the vehicle settings R
changing the convenience settings
R restoring the factory settings
Instrument cluster Selecting the unit of measurement for
distance
You can
determine

whether the multifunction
display shows some messages in miles or
kilometers.
X Press the = or ; button on the
steering wheel to select the Sett menu.
X Press the : or 9
button to select the
Inst. Cluster submenu.
X Press a to confirm.
X Press the :
or 9

button to select the
Display Unit Speed-/Odometer:
function.
You will see the selected setting km or
miles.
X Press the a button to save the setting.
The selected unit of measurement for
distance applies to:
R the digital speedometer in the Trip menu
R the odometer and the trip odometer
R the trip computer
R the current consumption and the range
R the navigation instructions in the Navi
menu
R cruise control
R DISTRONIC PLUS
R ASSYST PLUS service interval display
Switching the additional speedometer
on/off
Only vehicles
with

manual transmission have
this function.
X Press the = or ; button on the
steering wheel to select the Sett menu.
X Press the : or 9
button to select the
Inst. Cluster submenu.
X Press a to confirm.196
Menus and submenus
On-board computer and displays
ProCarManuals.com

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
ProCarManuals.com

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
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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
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