
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 194).
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
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Rat night, or if you are parking/maneuvering
your vehicle in a very dark area
R if very bright white light is shining on the
camera
R if the surrounding area is lit by fluorescent
light (the COMAND system display may
flicker)
R if the temperature changes suddenly, for
example if you drive into a heated garage
after being in the cold (condensation on the
lens)
R if the camera lens is dirty or covered
R if the rear of your vehicle is damaged
In this case, have the camera position and
setting checked at a qualified specialist
workshop. Mercedes-Benz recommends
that you use an authorized Mercedes-Benz
Center for this purpose.
Do not use the rear view camera in these
types of situation. Otherwise, you could injure
yourself and others and/or cause damage,
even to your own vehicle, when 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 highways
and arterial roads. It is active at speeds
between 50 mph (80 km/h) and 112 mph
(180 km/h).
If ATTENTION ASSIST detects fatigue or
increasing lapses in concentration on the part
of the driver, it suggests taking a break.GWarning!
The ATTENTION ASSIST is only an aid to the
driver. It might not recognize fatigue or
increasing inattentiveness in time or fail to
recognize them at all. The system cannot
substitute a rested and attentive driver.
Fatigue can cause you to recognize dangers
too late, to misjudge potential dangers, or to
react slower. Therefore, make sure to be
rested before and during your trip. Take rests
early enough and regularly, especially during
long trips. Failure to do so could cause you to
recognize dangers too late which could result
in an accident and serious injury to you and/
or 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 journey details, e.g. time of day and length
of journey
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
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
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Warning and display messages in the
multifunction display
Example
XActivate ATTENTION ASSIST using the on-
board computer ( Y page 228).
Symbol : appears in the multifunction
display.
If ATTENTION ASSIST is active, it will not warn
you until at least 20 minutes after your
journey has begun. You 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 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; it reassesses your
tiredness 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. A
camera at the top of the windshield picks up
the infrared light and displays a black-and-
white 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 because of 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
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
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pedestrians cannot be gauged accurately by
looking at a screen.
It may be the case that objects are highlighted
as well as pedestrians.GWarning!
The pedestrian detection may be impaired or
unavailable when
R pedestrians are obstructed fully or in part
by other objects such as parking vehicles
R the silhouette in the Night View Assist Plus
image is displayed incomplete or
interrupted, e.g. by significant light
reflection
R a pedestrian's silhouette is not rich enough
in contrast compared to the background
R pedestrians are not in erected position but,
for example, sit, crouch down, or lie
i Animals are not recognized by pedestrian
recognition.
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 142) 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 316).204Driving systemsDriving and parking
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If Blind Spot Assist is switched on, indicator
lamp : in the exterior mirrors lights up in
yellow up to a speed of 20 mph (30 km/h). 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 in 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.
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 232) and Blind Spot Assist
(Y page 228) are activated in the on-board
computer.
XTurn the SmartKey to position 2 in the
ignition lock.
Warning lamps : light up in 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 select km on the on-board computer in
the Display Unit Speed-/Odometer:
function (Y page 229), Lane Keeping Assist
is activated starting at a speed 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.
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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, such as
ABS, BAS or ESP ®
.
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Activating Lane Keeping AssistXActivate Lane Keeping Assist using the on-
board computer ( Y page 229).
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.
Active Driving Assistance package
General information
The Active Driving Assistance package
consists of DISTRONIC PLUS ( Y page 179),
Active Blind Spot Assist ( Y page 209) and
Active Lane Keeping Assist ( Y page 211).
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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
the edge of their lane that 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, the system may be
unable to distinguish the neighboring lane
from the one beyond it. For this reason, the
system may indicate vehicles in the farther
lane, especially if the vehicles are driving in a
staggered formation in different lanes. In
particular, this may be the case if the vehicles
are driving at that edge of their lane which is
nearest your vehicle. Due to the nature of the
system, warnings may be issued
unnecessarily when driving close to crash
barriers or similar solid lane borders.
Two Active Blind Spot Assist sensors are
integrated into the front and rear bumpers
respectively. An additional sensor is located
behind the cover in the radiator grill. Make
sure that the bumpers are free of dirt, ice or
slush around the sensors. The rear radar
sensors must not be covered, for example by
bicycle racks or overhanging loads. In the
event of a severe impact or damage to the
bumpers, have the function of the radar
sensors checked at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center. Active Blind Spot Assist may
otherwise fail to work correctly.
Indicator and warning display:Yellow indicator lamp/red warning lamp
If Active Blind Spot Assist is switched on,
indicator lamp : in the exterior mirrors lights
up in yellow up to a speed of 20 mph
(30 km/h). At speeds above 20 mph
(30 km/h), the indicator lamp goes out and
Active 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 in 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. Active Blind Spot Assist is
then no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.
GWarning
Active Blind Spot Assist is not active at speeds
lower than 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.
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Optical and acoustic collision warning
When you switch on the appropriate turn
signals to change lanes and a vehicle is
detected in the side monitoring range of
Active Blind Spot Assist, you receive an
optical and acoustic collision warning. You
then hear a double warning tone and 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.
Course-correcting brake application
If Active Blind Spot Assist detects a risk of
collision in the monitoring range, under
certain circumstances, it will brake the
vehicle briefly on one side. This is designed to
help you avoid a collision.
This function is available at speeds between
20 mph and 120 mph (30 km/h and
200 km/h).
When a course-correcting brake application
occurs, red warning lamp : flashes in the
exterior mirror and the following is shown in
the multifunction display, for example:GWarning
Active Blind Spot Assist is only an aid
designed to assist driving. It is not a substitute
for attentive driving. In some cases, the
course-correcting brake application is not
sufficient to avoid a collision. In such a case,
you must steer, brake or accelerate.
In very rare cases, the system may
erroneously detect a danger of collision in the
area of crash barriers or similar lane borders
and apply the brakes. Active Blind Spot Assist
does not detect all traffic situations and road
users. Always make sure that there is
sufficient distance to the side for other traffic
or obstacles. An inappropriate brake
application may be interrupted at any time if
you steer slightly in the opposite direction or
accelerate.
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.
Either a very slight, course-correcting brake
application, or none at all, may occur if:
R other vehicles and/or objects, such as
crash barriers, are detected in the
immediate vicinity of your vehicle.
R a vehicle approaches you too closely at the
side.
R you have adopted a sporty driving style with
high cornering speeds.
R you clearly brake or accelerate.
R a driving safety system intervenes, such as
ESP ®
or PRE-SAFE ®
Brake.
R ESP ®
is deactivated.
R a loss of tire pressure or a defective tire has
been detected and shown in the display.
Activating Active Blind Spot AssistXMake sure that the radar sensor system
( Y page 232) and Active Blind Spot Assist
( Y page 228) are activated in the on-board
computer.XTurn the SmartKey to position 2 in the
ignition lock.
Warning lamps : light up in red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.
Active Lane Keeping Assist
Important safety notes
Active Lane Keeping Assist monitors the area
in front of your vehicle by means of a camera
at the top of the windshield. Active Lane
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