Page 201 of 376

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. Active Driving Assistance package
General notes The Active Driving Assistance package
consists of DISTRONIC PLUS
(Y page 167),
Active Blind Spot Assist (Y page 199) and
Active Lane Keeping Assist (Y page 203).
Active Blind Spot Assist Important safety notes
G
WARNING
Active Blind Spot Assist is only an aid, and
may detect vehicles/obstacles incorrectly or
not at all.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to snow,
rain, fog or spray.
R the rear and/or front sensors are dirty.
Active Blind Spot Assist may not detect
narrow vehicles, such as motorcycles or
bicycles, or may only detect them too late. It
cannot detect vehicles that are overtaken at
a
small distance and then enter the blind spot
area.
Active Blind Spot 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.
i USA only:
This device has been approved by the FCC
as a “Vehicular Radar System”. The radar
sensor is intended for use in an automotive
radar system only. Removal, tampering, or
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.
i Canada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the
device will void any warranties, and is not
permitted. Do not tamper with, alter, or use
the device in any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
General notes
Active Blind Spot Assist uses a radar sensor
system to monitor the side areas of your
vehicle which are in back of the driver. A
warning display in the exterior mirrors draws
your attention to vehicles detected in the
monitored area. If you then switch on the
corresponding turn signal to change lane, you
will also receive an optical and audible
warning. If a risk of lateral collision is
detected, corrective braking may help you Driving systems
199
Driving and parking Z
Page 202 of 376

avoid a collision. To support the course-
correcting brake application, Active Blind
Spot Assist uses the forward-facing radar
sensor
system. The free space in the direction
of travel is then evaluated.
Active Blind Spot Assist supports you from a
speed of approximately 20 mph (30 km/h).
For Active Blind Spot Assist to assist you
when driving, the radar sensor system must
be activated ( Y page 223) and operational.
Monitoring area G
WARNING
Active 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. No visual nor
audible warnings are emitted and the system
does not brake the vehicle to correct your
course.
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. Active Blind Spot Assist monitors the area up
to 10 ft (
3.0m) behind your vehicle and
directly next to your vehicle, as shown in the
diagram. For this purpose, Active 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 there are vehicles at the inner
edge of your 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, for example
lorries, for a prolonged time.
The Active Blind Spot Assist radar sensors are
integrated into the front and rear bumpers
and behind a cover in the radiator grill. Make
sure that the bumpers and the cover in the
radiator grill are free of dirt, ice or slush. The
rear sensors must not be covered, for
example by cycle racks or overhanging cargo.
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. Active Blind Spot Assist
may otherwise no longer work properly. 200
Driving systems
Driving and parking
Page 203 of 376

Indicator and warning display
G
WARNING
Active Blind Spot Assist is not active at speeds
below 20 mph (30km/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. :
Yellow indicator lamp/red warning lamp
When Active Blind Spot Assist is activated,
indicator
lamp : in the exterior mirrors lights
up yellow at speeds of up to
20 mph(30km/h). At speeds above 20 mph
(30km/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 (30km/h), warning lamp : on the
corresponding side lights up red. This warning
is always given 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 (12km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Active Blind
Spot Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light. Visual and audible collision warnings
If you switch on the turn signals to change
lanes and a vehicle is detected in the side
monitoring range, you receive a visual 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 G
WARNING
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 on 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 driving at appropriate
speeds, 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. Driving systems
201Driving and parking Z
Page 204 of 376

If Active Blind Spot Assist detects a risk of a
lateral collision in the monitoring range, a
course-correcting
brake application is carried
out. This is meant to assist you in avoiding a
collision.
If a course-correcting brake application
occurs, red warning lamp : flashes in the
exterior mirror and a dual warning tone
sounds. In addition, the message shown in
the illustration appears in the multifunction
display.
The course-correcting brake application is
available in the speed range between 20 mph
(30 km/h) and120 mph (200km/h).
Either no braking application, or a course-
correcting brake application adapted to the
driving situation occurs if:
R there are vehicles or obstacles, e.g. crash
barriers, located on both sides 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, e.g.
ESP ®
or PRE-SAFE ®
Brake. R
ESP ®
is switched off.
R a loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist
X Make sure that the radar sensor system
(Y page 223) and Active Blind Spot Assist
(Y page
219) are activated in the on-board
computer.
X Turn 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.
Active Lane Keeping Assist Important safety notes
G
WARNING
Active 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.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to
inadequate
illumination of the road surface,
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 as a result the lane markings
cannot be recognized.
R the lane markings on the road are unclear,
e.g. near roadworks.202
Driving systems
Driving and parking
Page 205 of 376

R
the lane markings change quickly, e.g.
branch off, cross or merge.
R the road is narrow and winding.
Active 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.
General 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 Keeping Assist detects lane markings on
the road and warns you before you leave your
lane unintentionally. If you do not react to the
warning, a lane-correcting application of the
brakes can bring the vehicle back into the
original lane.
If you have selected km as the display unit in
the Display Unit Speed-/
Odometer(Y page 220) function in the on-
board computer, Active Lane Keeping Assist
assists you at speeds above 60 km/h. If
miles is selected as the display unit, the
assistance range starts at 40 mph. Warning vibration in the steering wheel
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.
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.
Lane-correcting brake application G
WARNING
Active Lane Keeping Assist does not keep
your vehicle in its lane. It is only an aid
designed
to assist driving. It is not a substitute
for attentive driving. In some cases, the lane-
correcting brake application is not sufficient
to bring your vehicle back to the original lane.
In such cases, you must steer the vehicle
yourself to ensure that it does not leave the
lane.
Active Lane Keeping Assist does not detect
road and traffic conditions. Always make sure
that there is sufficient distance to the side for
other traffic or obstacles. In rare cases,
unclear markings or particular structures on
the roadway can be recognized as solid lane
markings. An inappropriate brake application,
e.g. after intentionally driving over a solid lane
marking, may be interrupted at any time by
steering slightly in the opposite direction.
Active Lane Keeping Assist cannot take
weather conditions into account.
You are responsible for the driving at
appropriate speeds, braking in good time, and
steering correctly. Always adapt your driving Driving systems
203
Driving and parking
Z
Page 206 of 376

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.
The message shown in the illustration
appears in the multifunction display when a
lane-correcting brake application occurs.
If you leave your lane under certain
circumstances the vehicle will brake briefly
on one side. This is meant to assist you in
bringing the vehicle back to the original lane.
This function is available in the range between
40 mph and 120 mph (60 km/h and
200 km/h).
A lane-correcting brake application can only
be made after driving over a solid,
recognizable lane marking. Before this, a
warning must be given by means of
intermittent vibration in the steering wheel.
In addition, a lane with lane markings on both
sides must be recognized. The brake
application also slightly reduces vehicle
speed.
i A further lane-correcting brake
application can only occur after your
vehicle has returned to the original lane.
No lane-correcting brake application occurs
if:
R you clearly and actively steer, brake or
accelerate.
R you cut the corner on a sharp bend.
R you have switched on the turn signals.
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R you have adopted a sporty driving style with
high cornering speeds or high rates of
acceleration.
R ESP ®
is switched off. R
the transmission is not in position D.
R a
loss of tire pressure or a defective tire has
been detected and displayed.
Active Lane Keeping Assist does not detect
traffic situations or road users. An
inappropriate brake application may be
interrupted at any time if you:
R steer slightly in the opposite direction.
R use a turn signal.
R clearly brake or accelerate.
A lane-correcting brake application is
interrupted automatically if:
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R lane markings can no longer be recognized.
Switching on Active Lane Keeping Assist X
Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive(Y page 219).
Symbol : appears in the multifunction
display.
If your speed exceeds
40 mph (60 km/h)
and lane markings are detected,
symbol : is highlighted in green. Active
Lane Keeping Assist is ready for use.
If Standard is selected, no warning
vibration occurs if:
R you have switched 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 ®
.
If Adaptive is selected, no warning
vibration occurs if: 204
Driving systems
Driving and parking
Page 207 of 376

R
you have switched 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 lane quickly.
R you cut the corner on a sharp bend.
X Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive(Y page 219).
Symbol : appears in the multifunction
display.
If your speed exceeds
40 mph (60 km/h)
and lane markings are detected,
symbol : is highlighted. Active Lane
Keeping Assist is ready for use.
If Standard is selected, no warning
vibration occurs if:
R you have switched 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 ®
.
If Adaptive is selected, no warning
vibration occurs if:
R you have switched 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 lane quickly.
R you cut the corner on a sharp bend. Driving systems
205
Driving and parking Z
Page 208 of 376