warning light MERCEDES-BENZ B-CLASS 2012 Workshop Manual

Other vehicles changing lanes
DISTRONIC PLUS has not detected the
vehicle cutting in yet. The distance to this
vehicle will be too short.
Narrow vehicles
DISTRONIC PLUS has not yet detected the
vehicle in front on the edge of the road,
because of its narrow width. The distance to
the vehicle in front will be too short.
Obstructions and stationary vehicles
DISTRONIC PLUS does not brake for
obstacles or stationary vehicles. If, for example, the detected vehicle turns a corner
and reveals
an
obstacle or stationary vehicle,
DISTRONIC PLUS will not brake for these.
Crossing vehicles DISTRONIC PLUS may detect vehicles that
are crossing
your

lane by mistake. Activating
DISTRONIC PLUS at traffic lights with
crossing traffic, for example, could cause
your vehicle to pull away unintentionally. HOLD function
Important safety notes G
WARNING
When leaving the vehicle, it can still roll away
despite being braked

by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply.
R the HOLD function has been deactivated by
pressing the accelerator pedal or the brake
pedal, e.g. by a vehicle occupant.
R the electrical system in the engine
compartment, the battery or the fuses have
been tampered with.
R the battery is disconnected
There is a risk of an accident.
If you wish to exit the vehicle, always turn off
the HOLD function and secure the vehicle
against rolling away. Driving systems
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Driving and parking Z
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Top view
The sensors must be free from dirt, ice or
slush. They can otherwise not function
correctly. Clean
the
sensors regularly, taking
care not to scratch or damage them
(Y page 275).
Front sensors Center Approx. 40in (approx.
100cm)
Corners Approx. 24in (approx.
60cm)
Rear sensors
Center Approx. 48 in (approx.
120 cm)
Corners Approx. 32in (approx.
80cm)
Minimum distance
Center Approx. 8in (approx. 20cm)
Corners Approx. 8in (approx. 20cm)
If there is an obstacle within this range, the
relevant warning displays light up and a
warning tone sounds. If the distance falls
below the minimum, the distance may no
longer be shown.
Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located on the dashboard above the center air vents.
The warning display for the rear area is
located on the headliner in the rear
compartment.
Warning display for the front area
:
Segments on the left-hand side of the
vehicle
; Segments on the right-hand side of the
vehicle
= Segments showing operational readiness
The warning display for each side of the
vehicle is divided

into five yellow and two red
segments. PARKTRONIC is operational if
yellow segments showing operational
readiness = light up.
The selected transmission position and the
direction in which the vehicle is rolling
determine which warning display is active
when the engine is running. Transmission
position Warning display
D
Front area activated
R, N or the vehicle
is rolling
backwards Rear and front areas
activated
P
No areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.170
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From the:
R
sixth segment onwards, you will hear an
intermittent warning tone for
approximately two seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two
seconds. This indicates that you have now
reached the minimum distance.
Deactivating/activating PARKTRONIC :
Indicator lamp
; To deactivate/activate PARKTRONIC
If indicator lamp : lights
up, PARKTRONIC is
deactivated.
i PARKTRONIC is automatically activated
when you turn the SmartKey to position 2
in the ignition lock. Driving systems
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Problems with PARKTRONIC
Problem Possible causes/consequences and
M SolutionsOnly the red segments
in the PARKTRONIC
warning displays
are
lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is
deactivated after
approximately
20 seconds, and the
indicator lamp in the
PARKTRONIC button
lights up. PARKTRONIC has malfunctioned and has switched off.
X
If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. Only the red segments
in the PARKTRONIC
warning displays
are

lit.
PARKTRONIC is
deactivated after
approximately
20seconds. The PARKTRONIC sensors are dirty or there is interference.
X
Clean the PARKTRONIC sensors ( Y page 275).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves.
X
See if PARKTRONIC functions in a different location. Active Parking Assist
Important safety notes Active Parking Assist is merely an aid. It is not
a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking
and exiting a parking space. When
maneuvering, parking or pulling out of a
parking space, make sure that there are no
persons, animals or objects in the area in
which you are maneuvering.
G
WARNING
The vehicle swings out when parking and in
doing so could cross into the opposite lane.
This could result in a collision with another
road user. There is a risk of an accident.
Pay attention to other road users when
parking. Stop the vehicle if necessary or cancel the Active Parking Assist parking
procedure.
! If unavoidable, you should drive over
obstacles such as curbs slowly and not at
a sharp angle.

Otherwise, you may damage
the wheels or tires.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for
parking, for example:
R where parking or stopping is prohibited
R in front of driveways or entrances and exits
R on unsuitable surfaces
Parking tips:
R On narrow roads, drive as close to the
parking space as possible.
R Parking spaces that are littered, overgrown
or partially occupied by trailer drawbars
might be identified incorrectly or not at all.172
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If you back up after activation, the steering
wheel is moved to the straight-ahead
position.
X Drive forwards or back up the vehicle, being
ready to brake at all times.
X Stop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
X Drive forwards and reverse as prompted by
the PARKTRONIC warning
displays, several
times if necessary.
Once you have exited the parking space
completely, the steering wheel is moved to
the straight-ahead position. You hear a tone
and the Park Assist Finished message
appears in the

multifunction display. You will
then have to steer and merge into traffic on
your own. PARKTRONIC is still available.
Canceling Active Parking Assist You can cancel Active Parking Assist at any
time.
X
Stop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at
once. The Park Assist Canceled
message appears in the multifunction
display.
or
X Press the PARKTRONIC button on the
center console (
Y

page 171).
PARKTRONIC is switched off and Active
Parking Assist is immediately canceled.
The Park Assist Canceled message
appears in the multifunction display.
Active Parking Assist is canceled
automatically if:
R you engage the electric parking brake.
R parking using Active Parking Assist is no
longer possible.
R you are driving faster than 6 mph
(10 km/h).
R a wheel

spins, ESP®
intervenes or fails. The
÷ warning lamp lights up in the
instrument cluster. A warning tone sounds. The parking space
symbol disappears and the multifunction
display shows the
Park Assist Canceled
message.
If Active
Parking

Assist is canceled, you must
steer again yourself.
If a system malfunction occurs, the vehicle is
braked to a standstill. To drive on, depress the
accelerator again. Rear view camera
Important safety notes The rear view camera is only an aid. It is not
a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering and
parking.
When
maneuvering

or parking, make
sure that there are no persons, animals or
objects in the area in which you are
maneuvering.
Under the following circumstances, the rear
view camera will not function, or will function
in a limited manner:
R the tailgate is open
R in heavy rain, snow or fog
R at night or in very dark places
R if the camera is exposed to very bright light
R if the area is lit by fluorescent light or LED
lighting (the display may flicker)
R if there is a sudden change in temperature,
e.g. when driving into a heated garage in
winter
R if the camera lens is dirty or obstructed
R if the rear of your vehicle is damaged. In
this event, have the camera position and
setting checked at a qualified specialist
workshop.176
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Lanes
:
White guide line without turning the
steering wheel, vehicle width including
the exterior mirrors (static)
; Yellow lane marking tires at current
steering wheel angle,
vehicle width to the
outer side of the wheels (dynamic)
= Red guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic)
? Bumper Guide lines
?
Bumper
A Red guide line at a distance of
approximately 10 in (0.25 m
) from the
rear of the vehicle
B Yellow guide line at a distance of
approximately

13 ft (
4.0 m) from the rear
of the vehicle
C Vehicle center axle (marker assistance)
D Yellow guide line at a distance of
approximately 3 ft (1.0 m ) from the rear
of the vehicle The lanes and guide lines are only displayed
if you have engaged reverse gear.
The distance specifications only apply to
objects that are at ground level.
Additional displays on vehicles with PARKTRONIC
and COMAND
:
Front warning display
; Additional PARKTRONIC measurement
operational readiness indicator
= Rear warning display
Vehicles with PARKTRONIC and
COMAND: if PARKTRONIC is operational
(Y page 169), an additional operational
readiness indicator will appear in COMAND
display ;.If the PARKTRONIC warning
displays are active or light up, warning
displays : and
=


are also active or light up
correspondingly in the COMAND display.
Reverse parking function X
Make sure that the rear view camera is
activated and the "Reverse parking"
function is selected; see the separate
operating instructions for the audio
system/COMAND.
The lane and the guide lines are shown.178
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monitored area. If you then switch on the
corresponding turn signal to change lanes,
you will also receive a visual and audible
collision warning.
For
this purpose, Blind Spot
Assist uses sensors in the rear bumper.
For Blind Spot Assist to assist you when
driving, the radar sensor system must be:
R activated(Y page 199)
R operational
Monitoring range of the sensors
In particular, the detection of obstacles can
be impaired if:
R dirt on the sensors or anything else
covering the sensors
R there is poor visibility, e.g. due to fog, heavy
rain or snow
R a narrow vehicle traveling in front, e.g. a
motorbike or bicycle
R the road has very wide lanes
R the road has narrow lanes
R you are not driving in the middle of the lane
R there are barriers or similar lane borders
Vehicles in the monitoring range are then not
indicated. Blind Spot Assist monitors the area up to
10 ft (
3.0 m

) behind your vehicle and directly
next to your vehicle, as shown in the diagram. For this purpose, Blind Spot Assist uses radar
sensors in the rear bumper.
If the
lanes

are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may
be indicated, especially if the vehicles are not
driving in the middle of their lane. This may
be the case if the vehicles are driving on the
inner side of their lane.
Due to the nature of the system:
R warnings may be issued in error when
driving close to crash barriers or similar
solid lane borders.
R warnings may be interrupted when driving
alongside particularly long vehicles, e.g.
trucks, for a prolonged time.
The two sensors for Blind Spot Assist are
integrated into the sides of the rear bumper.
Make sure that the bumper is free of dirt, ice
or slush in the vicinity of the sensors. For
example, the radar sensors must not be
covered by bicycle racks or overhanging
loads. Following a severe impact or in the
event of damage to the bumpers, have the
function of the radar sensors checked at a
qualified specialist workshop. Blind Spot
Assist may otherwise not work properly.
Indicator and warning display
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated. :
Yellow indicator lamp/red warning lamp
When Blind Spot Assist is activated, indicator
lamp : in the exterior mirrors lights up
yellow at speeds

of up to 20 mph (30 km/h).182
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At speeds above 20 mph (30 km/h) the
indicator lamp
goes
out and Blind Spot Assist
is operational.
If a vehicle is detected within the monitoring
range of Blind Spot Assist at speeds above
20 mph (30 km/h), warning lamp : on the
corresponding side lights up red. This warning
is always emitted when a vehicle enters the
blind spot monitoring range from behind or
from the side. When you overtake a vehicle,
the warning only occurs if the difference in
speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Blind Spot
Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the
corresponding turn signal, a double warning
tone sounds. Red warning lamp : flashes. If
the turn signal remains on, vehicles detected
are indicated by the flashing of red warning
lamp :. There are no further warning tones.
Switching on Blind Spot Assist
X Make sure that the radar sensor system
(Y page 199) and Blind Spot Assist
(Y page 195)
are

activated in the on-board
computer.
X Turn the SmartKey to position 2 in the
ignition lock.
Warning lamps : in the exterior mirrors
light up red for approximately
1.5 seconds and then turn yellow.
Lane Keeping Assist General notes
Lane Keeping Assist monitors the area in
front of
your

vehicle by means of a camera at
the top of the windshield. Lane Keeping Assist
detects lane markings on the road and warns you before you leave your lane
unintentionally.
:
Lane Keeping Assist camera
If you select km on the on-board computer in
the Display Unit Speed-/Odometer:
function ( Y page 196), Lane Keeping Assist
is active starting

at a speed of 60 km/h. If the
miles display unit is selected, the assistance
range begins at 40 mph.
Important safety notes G
WARNING
Lane Keeping Assist may not always clearly
recognize lane markings.
In this case, Lane Keeping Assist may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and stay in lane, in particular if
warned by Lane Keeping Assist. G
WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There
is a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane
Keeping Assist.
If you fail to adapt your driving style, Lane
Keeping Assist can

neither reduce the risk of
an accident nor override the laws of physics.
Lane Keeping Assist cannot take into account
the road, traffic and weather conditions. Lane Driving systems
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Keeping Assist is merely an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
The Lane Keeping Assist does not keep the
vehicle in the lane.
The system may be impaired or may not
function if:
R
there is poor visibility, e.g. due to
insufficient illumination of
the road, or due
to snow, rain, fog or spray
R there is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
R the windshield is dirty, fogged up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R there are no, several or unclear lane
markings for a lane, e.g. in areas with road
construction work
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow
R the distance to the vehicle in front is too
small and the lane markings thus cannot be
detected
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge
R the road is narrow and winding
R there are strong shadows cast on the lane
A warning may be given if a front wheel
passes over a lane marking. It will warn you
by means of intermittent vibration in the
steering wheel for up to 1.5 seconds.
Switching on Lane Keeping Assist X
Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive (Y page 195).
Symbol : appears in the multifunction
display.
If you drive at speeds above 40 mph
(60 km/h
) and lane markings are detected,
symbol : is highlighted. Lane Keeping
Assist is ready for use.
When Standard is selected, no warning
vibration occurs if:
R you switch on

the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, such as
ABS, BAS or ESP ®
.
When Adaptive is selected, no warning
vibration occurs if:
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard.
R you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when
necessary and in good time if you cross the
lane marking, the system recognizes certain
conditions and warns you accordingly.
The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend.
R the road has very wide lanes, e.g. a
freeway.
R the system recognizes solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.184
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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note
that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 24).Important safety notes
G
WARNING
If you operate information systems and
communication equipment integrated in the
vehicle while driving, you will be distracted
from traffic conditions. You could also lose
control of the vehicle. There is a risk of an
accident.
Only operate the equipment when the traffic
situation permits. If

you are not sure that this
is possible, park the vehicle paying attention
to traffic conditions and operate the
equipment when the vehicle is stationary. G
WARNING
If the instrument cluster has failed or
malfunctioned, you may not recognize
function restrictions in systems relevant to
safety. The operating safety of your vehicle
may be impaired. There is a risk of an
accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop
immediately.
You must observe the legal requirements for
the country in

which you are currently driving
when operating the on-board computer.
The on-board computer only shows messages
or warnings from certain systems in the multifunction display. You should therefore
make sure your vehicle is operating safely at
all times. Otherwise, a vehicle that is not
operating safely may cause an accident.
For an overview, see the instrument panel
illustration (
Y page 29). Displays and operation
Instrument cluster lighting
The lighting in the instrument cluster, in the
displays and the controls in the vehicle
interior can be

adjusted using the brightness
control knob.
The brightness control knob is located on the
bottom left of the instrument cluster
(Y page 29).
X Turn the brightness control knob clockwise
or counter-clockwise.
If the light switch is set to Ã, T or
L, the brightness is dependent upon
the brightness of the ambient light.
i The light sensor

in the instrument cluster
automatically controls the brightness of
the multifunction display.
In daylight, the displays in the instrument
cluster are not illuminated. Coolant temperature display
G
WARNING
Driving when your engine is overheated can
cause some fluids

which may have leaked into
the engine compartment to catch fire. You
could be seriously burned.
Steam from an overheated engine can cause
serious burns which can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Stop the vehicle in a safe location away from
other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until
the engine has cooled down. 186
Displays and operation
On-board computer and displays
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