warning light MERCEDES-BENZ E-Class WAGON 2012 W212 Repair Manual

Range of the sensors
General notes
The sensors must be free of dirt, ice and
slush; otherwise they may not function
correctly. Clean the sensors regularly, taking
care not to scratch or damage them
( Y page 317).
Side view, Sedan (example)
Top view, Sedan (example)
Front sensors
CenterApproximately 40 in
(approximately 100 cm)CornersApproximately 24 in
(approximately 60 cm)
Rear sensors
CenterApproximately 48 in
(approximately 120 cm)CornersApproximately 32 in
(approximately 80 cm)! When parking, pay particular attention to
objects above or below the sensors, such
as flower pots or trailer drawbars.
PARKTRONIC does not detect such objects
when they are in the immediate vicinity of
the vehicle. You could damage the vehicle
or the objects.
The sensors may not detect snow and other
objects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic
car wash, the compressed-air brakes on a
truck or a pneumatic drill could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
Minimum distanceCenterApproximately 8 in
(approximately 20 cm)CornersApproximately 6 in
(approximately 15 cm)
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.
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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
determines which warning display is active
when the engine is running.
Transmission
positionWarning displayDFront area activatedR or NRear and front areas
activatedPNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
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:To deactivate/activate PARKTRONIC;Indicator lamp
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.
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Problems with PARKTRONICProblemPossible 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.XIf 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 20
seconds.The PARKTRONIC sensors are dirty or there is interference.XClean the PARKTRONIC sensors ( Y page 317).XSwitch the ignition back on.The problem may be caused by an external source of radio or
ultrasound waves.XSee if PARKTRONIC functions in a different location.Parking Guidance
Important safety notes
Parking Guidance is an electronic parking aid
with ultrasound. Ultrasound is used to
measure the road on both sides of the vehicle.
A suitable parking space is indicated by the
parking symbol. You receive steering
instructions when parking. You may also use
PARKTRONIC ( Y page 192).
GWARNING
Parking Guidance is merely an aid and may
display parking spaces that are not suitable
for parking, for example:
R no-parking areas
R parking spaces with unsuitable surfaces
(road surface)
R driveways
R entrances and exits
Parking Guidance detects and measures
potential parking spaces while driving past.
Changes to the parking space after this point
are not taken into account, for example if the
vehicle in front of or behind the parking space
changes position or objects in the parking
space are moved.
Even when using Parking Guidance, you are
still responsible for driving carefully. If you
rely on Parking Guidance alone, you could
cause an accident and injure yourself and
others.
Safety always remains your responsibility and
you must continue paying careful attention to
your immediate surroundings when parking
and maneuvering.Driving systems195Driving and parkingZ

Rthe trunk lid/the tailgate is open
R it is raining or snowing strongly or if it is
foggy
R it is night or if you are parking/
maneuvering your vehicle in a very dark
area
R a very bright white light is affecting the
camera
R the immediate vicinity is illuminated with
fluorescent light (the display of the
COMAND system can flicker)
R temperature changes abruptly, for example
if you drive out of the cold into a heated
garage (condensation on the lens)
R the camera lens is dirty or covered
R the rear of your vehicle is damaged
In this case, have the position and the
setting of the camera checked at a
specialist workshop. Mercedes-Benz
recommends that you consult a Mercedes-
Benz Center for this purpose.
Do not use the rear view camera in these
situations. You could otherwise injure
yourself and other people and/or cause
damage - including damage to your vehicle -
while parking/maneuvering.
Activating the rear view cameraXMake sure that the SmartKey is in position
2 in the ignition lock.XMake sure that the "rear view camera"
function is selected in COMAND (see the
separate operating instructions for
COMAND).XEngage reverse gear.
The area behind the vehicle is shown in the
COMAND display.
ATTENTION ASSIST
Important safety notes
ATTENTION ASSIST helps you during long,
monotonous journeys such as on freeways
and interstate highways. It is active in the
range between 50 mph (80 km/h) and
112 mph (180 km/h).
If ATTENTION ASSIST detects typical
indicators of fatigue or increasing lapses in
concentration on the part of the driver, it
suggests you take a break.GWARNING
ATTENTION ASSIST is only an aid and may
detect your tiredness or lapses in
concentration too late or not at all. It is not a
substitute for a well-rested and attentive
driver.
Fatigue may cause you to recognize
hazardous situations too late, misjudge a
situation or react more slowly. For this
reason, make sure you feel rested before you
begin driving and during your journey. Make
sure that you take regular breaks in time,
particularly on long journeys. Otherwise, you
may fail to recognize dangers in time, cause
an accident and injure yourself and others.
ATTENTION ASSIST assesses your level of
fatigue or lapses in concentration by taking
the following criteria into account:
R your personal driving style, e.g. steering
characteristics
R driving conditions, e.g. time, driving time
The functionality of ATTENTION ASSIST is
restricted and warnings may be delayed or
not occur at all:
R if the road condition is poor, e.g. if the
surface is uneven or if there are potholes
R if there is a strong side wind
R if you have adopted a sporty driving style
with high cornering speeds or high rates of
acceleration
R if you predominantly drive at speeds under
50 mph (80 km/h) or over 112 mph
(180 km/h)
R if you are currently using COMAND or
making a telephone call with it
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Rif the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
Warning and display messages in the
multifunction displayXActivate ATTENTION ASSIST using the on-
board computer ( Y page 225).
Symbol : appears in the multifunction
display.
If ATTENTION ASSIST is active, you will be
warned no sooner than 20 minutes after your
journey has begun. You will then hear an
intermittent warning tone twice, and the
Attention Assist: Time for a rest?
message appears in the multifunction
display.
XIf necessary, take a break.XPress a to confirm the message.
On long journeys, take regular breaks in good
time to allow yourself to rest properly. If you
do not take a break and ATTENTION ASSIST
still detects typical indicators of fatigue or
increasing lapses in concentration, you will be
warned again after 15 minutes at the earliest.
ATTENTION ASSIST is reset when you
continue your journey and starts assessing
your tiredness again if:
R you switch off the engine.
R you take off your seat belt and open the
driver's door, e.g. for a change of drivers or
to take a break.
Night View Assist Plus
Important safety notes
In addition to the illumination provided by the
normal headlamps, Night View Assist Plus
uses infrared light to illuminate the road. The
Night View Assist Plus camera picks up the
infrared light and displays a grayscale image
in the COMAND display. The image displayed
in COMAND corresponds to a road lit up by
high-beam headlamps. This enables you to
see the road's course and any obstacles in
good time. If pedestrian recognition is
activated, pedestrians recognized by the
system are highlighted in the Night View
Assist Plus display.
GWARNING
Night View Assist Plus is only an aid designed
to assist driving. It is not a substitute for
attentive driving. Do not rely solely on the
Night View Assist Plus display. Continue to
look through the windshield. You are
responsible for safety and must drive in
accordance with traffic conditions. You could
otherwise put yourself and others in danger.
The system may be impaired or unavailable if:
R there is poor visibility, e.g. due to snow,
rain, fog or heavy spray.
R the windshield is dirty, fogged up or
covered, for instance by a sticker, in the
vicinity of the camera.
R you are driving on bends, uphill gradients
or downhill gradients.
Light from the headlamps of oncoming
vehicles does not affect the Night View Assist
Plus display in the multifunction display. This
is also the case if you cannot switch on the
high-beam headlamps due to oncoming
traffic.
GWARNING
The Night View Assist Plus cannot record
objects immediately in front of or next to the
vehicle. When maneuvering, continue to look
through the windshield. Make sure no
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persons or animals are in the area in which
you are maneuvering. You could otherwise
injure them.
i Infrared light is not visible to the human
eye and therefore does not glare. Night
View Assist Plus can therefore remain
switched on even if there is oncoming
traffic.:Night View Assist Plus camera
Switching on Night View Assist Plus
Depending on your vehicle's date of
manufacture, the c or à symbol for
the "Automatic driving lights/daytime
running lamps" position is located on the light
switch.
You can only activate Night View Assist Plus
if:
R the SmartKey is in position 2 in the ignition
lock.
R it is dark.
Rthe light switch is set to either c,
à or L .
R reverse gear has not been engaged.XMake sure that COMAND is switched on.XPress button :.
The Night View Assist Plus display appears
in the COMAND display.:Night View Assist Plus display;Pedestrian recognized=Framing?Symbol for active pedestrian recognition
You can read about how to adjust the
brightness of the COMAND display in the
COMAND operating instructions.
i The infrared lamps switch on
automatically from a speed of about 6 mph
( 10 km/h). This means that you do not have
the full visual range while the vehicle is
stationary and cannot check whether Night
View Assist Plus is working.
Pedestrian recognition
GWARNING
Pedestrian recognition may be impaired or
inoperative if:
R pedestrians are partially or entirely
obscured by objects, e.g. parked vehicles.
R the silhouette of the pedestrian in the Night
View Assist Plus display is incomplete or
interrupted, e.g. by powerful light
reflections.
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Rpedestrians do not contrast with the
surroundings.
R pedestrians are not standing upright, for
example, if they are sitting, crouching or
lying down.
i Animals are not recognized by pedestrian
recognition.
Night View Assist Plus is able to recognize
pedestrians by typical characteristics, e.g. a
silhouette in the shape of a person.
Pedestrian recognition is then switched on
automatically if:
R Night View Assist Plus is activated.
R you are driving faster than 6 mph
(10 km/h).
R the surroundings are dark, e.g. when
driving outside built-up areas without
street lighting.
If pedestrian recognition is active,
symbol ? appears. If pedestrians are
recognized, they are framed = and thereby
highlighted. If the pedestrian recognition
system has brought a pedestrian to your
attention, look through the windshield to
evaluate the situation. The actual distance to
objects and pedestrians cannot be gauged
accurately by looking at a screen.
It may be the case that objects are highlighted
as well as pedestrians.
Fogged up or dirty windshield
If the windshield in front of the camera is
fogged up or dirty on the inside or outside, the
Night View Assist Plus display is affected.
GWARNING
Please do not forget that your primary
responsibility is to drive the vehicle. A driver's
attention to the road must always be his/her
primary focus when driving. For your safety
and the safety of others, stop before trying to
remove window fogging or cleaning the
windshield in front of the Night View Assist
Plus camera.
Bear in mind that at a speed of just 30 mph
(approximately 50 km/h), your vehicle is
covering a distance of 44 feet
(approximately 14 m) every second.XTo defrost: check the automatic air
conditioning settings (Y page 138) and fold
down the camera cover ( Y page 318).XTo defrost the inside of the windshield:
fold down the camera cover ( Y page 318)
and clean the windshield ( Y page 317).202Driving systemsDriving and parking

altering of the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
For Blind Spot Assist to assist you when
driving, the radar sensor system must be
activated ( Y page 229) and operational.
Monitoring range of the sensors
Blind Spot Assist monitors the area shown in
the figure up to 10 ft (3 m) behind and
immediately adjacent to your vehicle.
Example: Sedan
GWARNING
Blind Spot Assist monitors certain areas in the
immediate vicinity of your vehicle. Vehicles
that approach and drive past at high speeds
are not detected. There is no display and no
warning.
If the lanes are very wide, it may not be
possible to monitor the complete width of the
neighboring lane. For this reason, vehicles in
the next lane may not be detected, especially
if they are driving in a staggered formation.
This may be the case if vehicles are driving at
that edge of their lane which is furthest away
from your vehicle.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
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 long vehicles, such as 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 from dirt,
ice or slush around the sensors. The rear
sensors must not be covered, for example 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, e.g. an authorized Mercedes-Benz
Center. Blind Spot Assist may otherwise not
work properly.
Indicator and warning display:Yellow indicator lamp/red warning lamp
When Blind Spot Assist is activated, indicator
lamp : lights up yellow in the exterior
mirrors up to a vehicle speed of 20 mph
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(30 km/h). When the vehicle speed exceeds
20 mph (30 km/h), the indicator lamp goes
out and Blind Spot Assist is ready for use.
When your speed exceeds approximately
20 mph (30 km/h), warning lamp : lights up
red on the corresponding side whenever a
vehicle is detected in the blind spot
monitoring range. This warning is always
given when a vehicle enters the blind spot
monitoring range from behind or from the
side. When you are passing another vehicle,
the warning is emitted only 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.GWARNING
Blind Spot Assist is not active at speeds under
approximately 20 mph (30 km/h). The
indicator lamps in the exterior mirrors are
yellow. Vehicles in the monitoring range are
then not indicated.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the turn
signal, a double warning tone sounds. Red
warning lamp : flashes. If the turn signal
remains on, detected vehicles are indicated
by the flashing of red warning lamp :. There
are no further warning tones.
Switching on Blind Spot Assist
XMake sure that the radar sensor system
( Y page 229) and Blind Spot Assist(Y page 225) are activated in the on-board
computer.XTurn the SmartKey to position 2 in the
ignition lock.
Warning lamps : light up red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.
Lane Keeping Assist
Important safety 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 have chosen the Display Unit
Speed-/Odometer (Y page 226) function in
the on-board computer and select km as the
unit of measurement, Active Lane Keeping
Assist is active from speeds of 60 km/h. If
the miles display unit is selected, the
assistance range begins at 40 mph.
GWARNING
Lane Keeping Assist does not keep your
vehicle in its lane. It is only an aid and may
detect the lane markings on the road
incorrectly or not at all.
Driving systems205Driving and parkingZ

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 reflection from other vehicles.
R the windshield is dirty, fogged up or
covered, for instance by a sticker, in the
vicinity of the camera.
R several or no lane markings for a single lane
are present.
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 on the road are unclear,
e.g. near roadworks.
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge.
R the road is narrow and winding.
Lane Keeping Assist cannot detect road and
traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, braking in good time, and
steering correctly. Always adapt your driving
style to suit the prevailing road and weather
conditions. Always pay attention to traffic
conditions and your surroundings. Otherwise,
you may fail to recognize dangers in time,
cause an accident and injure yourself and
others.
A warning can be given when 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.
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.
No warning vibration occurs if:
R you clearly and actively steer, brake or
accelerate.
R you cut the corner on a sharp bend.
R a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Switching on Lane Keeping AssistXActivate Lane Keeping Assist using the on-
board computer ( Y page 225).
Symbol : appears in the multifunction
display.
If your speed exceeds 40 mph (60 km/h)
and lane markings are detected,
symbol : is highlighted. Lane Keeping
Assist is ready for use.
Active Driving Assistance package
General notes
The Active Driving Assistance package
consists of DISTRONIC PLUS ( Y page 177),
Active Blind Spot Assist ( Y page 207) and
Active Lane Keeping Assist ( Y page 210).
206Driving systemsDriving and parking