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Rif you have adopted a sporty driving style withhigh cornering speeds or high rates of accel-
eration
Rif you are predominantly driving at a speed
below 37 mph (60 km/h) or above 124 mph
(200 km/h)
Rif you are driving with the Steering Pilot of
Distance Pilot DISTRONIC activated
Rif the time has been set incorrectly
Rin active driving situations, such as when you
change lanes or change your speed
The ATTENTION ASSIST tiredness assessment
is deleted and restarted when continuing the
journey, if:
Ryou switch off the engine
Ryou take off your seat belt and open the driv-
er's door, e.g. for a change of drivers or to
take a break
Displaying the attention level
In the Assistance menu (Ypage 222) of the on-
board computer, you can call up the current sta-
tus information.
XSelect the Assistance display for ATTENTION
ASSIST using the on-board computer
(
Ypage 221).
The following information appears:
RThe length of the journey since the last break.
Rthe attention level determined by ATTENTION ASSIST (Attention Level), displayed in a
bar display in five levels from high to low.
Rif ATTENTION ASSIST is unable to calculate
the attention level and cannot issue a warn-
ing, the System Suspended
message
appears. The bar display then changes the
display, e.g. if you are driving at a speed below
37 mph (60 km/h) or above 124 mph
(200 km/h).
Activating ATTENTION ASSIST
XActivate ATTENTION ASSIST using the on-
board computer (Ypage 223).
The system determines the attention level of
the driver depending on the setting selected:
Selection Standard
: the sensitivity with which
the system determines the attention level is set
to normal.
Selection Sensitive
: the sensitivity is set
higher. The attention level detected by Attention
Assist is adapted accordingly and the driver is
warned earlier.
When ATTENTION ASSIST is deactivated, the
é symbol appears in the multifunction dis-
play in the assistance graphic display.
When ATTENTION ASSIST has been deactivated,
it is automatically reactivated after the engine
has been stopped. The sensitivity selected cor-
responds to the last selection activated (stand-
ard/sensitive).
Warning in the multifunction display
If fatigue or increasing lapses in concentration
are detected, a warning appears in the multi-
function display: ATTENTION ASSIST
Take aBreak!.
In addition to the message shown in the multi-
function display, you will then hear a warning
tone.
XIf necessary, take a break.
XConfirm the message by pressing the a
button on the steering wheel.
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 con-
tinues to detect increasing lapses in concentra-
tion, you will be warned again after 15 minutes
at the earliest. This will only happen if ATTEN-
TION ASSIST still detects typical indicators of
fatigue or increasing lapses in concentration.
Vehicles with COMAND multimedia system:
if a warning appears in the multifunction display, a service station search is performed in the mul-
timedia system. You can select a service station
and navigation to this service station will then
begin. This function can be activated and deac-
tivated in the COMAND multimedia system (see
the Digital Operator's Manual).
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Traffic Sign Assist
General notes
Traffic Sign Assist displays the maximum speed
permitted to the driver in the instrument cluster.
The data and general traffic regulations stored in
the navigation system are used to determine the
current speed limit.
Traffic Sign Assist is a map-based system, and
for this reason, traffic signs put up temporarily
(e.g. near roadworks) are not detected. There is also no display for changing traffic signs.
Traffic signs with a restriction indicated by an
additional sign (e.g. in wet conditions) are also
shown.
The sign indicating the end of a restriction only
appears with the restriction in the instrument
cluster when:
RThe regulation must be observed with the
restriction, or
RTraffic Sign Assist is unable to determine
whether the restriction applies
If Traffic Sign Assist is unable to determine a
maximum permitted speed from any of the avail-
able sources, no speed limit appears in the
instrument cluster either.
Traffic Sign Assist is not available in all coun-
tries. In this case, display :appears in the
assistance graphic (
Ypage 221).
Important safety notes
Traffic Sign Assist is only an aid and is not always
able to correctly display speed limits. Traffic
signs always have priority over the Traffic Sign
Assist display.
The system may be either functionally impaired
or temporarily unavailable if the information in
the digital street map of the navigation system is
incorrect or out of date.
Instrument cluster display
Displaying the assistance graphic
XCall up the assistance graphic display func-
tion using the on-board computer
(
Ypage 221).
Detected traffic signs appear in the instru-
ment cluster.
Speed limit with unknown restriction
:Maximum permitted speed
;Maximum permitted speed for vehicles for
which the restriction in the additional sign is relevant
=Additional sign for unknown restriction
A maximum permitted speed of 80 mph
(80 km/h) and a speed limit of 60 mph
(60 km/h) with an unknown restriction apply.
The unit for the speed limit (km/h or mph)
depends on the country in which you are driving. It is generally neither shown on the traffic sign
nor on the instrument cluster but must be taken
into account when observing the maximum per-
mitted speed.
Lane Tracking package
General notes
The Lane Tracking package consists of Blind
Spot Assist (Ypage 200) and Lane Keeping
Assist (Ypage 202).
Blind Spot Assist
General notes
Blind Spot Assist monitors the areas on either
side of the vehicle that are not visible to the
driver with two lateral, rear-facing radar sen-
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sors. A warning lamp lights up in the exterior
mirrors and 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.
Blind Spot Assist supports you from a speed of
approximately 20 mph (30 km/h).
Important safety notes
GWARNING
Blind Spot Assist does not react to:
Rvehicles overtaken too closely on the side,
placing them in the blind spot area
Rvehicles which approach with a large speed
differential and overtake your vehicle
As a result, Blind Spot Assist may not give
warnings in such situations. There is a risk of
an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
Blind Spot Assist is only an aid. It may fail to
detect some vehicles and is no substitute for
attentive driving. Always ensure that there is
sufficient distance to the side for other road
users and obstacles.
iUSA 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. Removing, tampering with, or
altering the device will void any warranties,
and is not permitted by the FCC. Do not tam-
per 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.
Radar sensors
The radar sensors for Blind Spot Assist are inte-
grated into the rear bumper. Make sure that the bumpers are free from dirt, ice or slush. The
sensors must not be covered, for example by
cycle 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 no longer work properly.
Monitoring area
In particular, the detection of obstacles can be
impaired if:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is poor visibility, e.g. due to fog, heavy
rain, snow or spray
Rthere are narrow vehicles, e.g. motorcycles or
bicycles
Rthe road has very wide lanes
Rthe road has narrow lanes
Ryou are not driving in the middle of the lane
Rthere are barriers or other road boundaries
Vehicles in the monitoring range are then not
indicated.
At a distance of around 1.6 ft (0.5 m) ;from the
vehicle, Blind Spot Assist monitors the area up
to 10 ft (3 m) next to =and behind :your
vehicle, as shown in the picture.
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 driv-
ing in the middle of their lane. This may be the
case if there are vehicles driving at the inner
edge of their lanes.
Due to the nature of the system:
Rwarnings may be issued in error when driving
close to crash barriers or similar solid lane
borders.
Rwarnings may be interrupted when driving
alongside long vehicles, e.g. trucks, for a pro-
longed time.
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Warning lamp
:Warning lamp
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp :on the correspond-
ing 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).
If you select the reverse gear, Blind Spot Assist is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
Collision warning
If a vehicle is detected in the monitoring range of
Blind Spot Assist and you switch on the corre-
sponding turn signal, a double warning tone
sounds. The red warning lamp flashes on the
relevant exterior mirror. If the turn signal
remains on, detected vehicles are indicated by
the flashing of the red warning lamp on the exte-
rior mirror. There are no further warning tones.
Switching on Blind Spot Assist
XMake sure that Blind Spot Assist is activated
in the on-board computer (Ypage 223).
XTurn the SmartKey to position 2in the igni-
tion lock.
The red warning lamps on the exterior mirrors
light up until the engine is started.
Display in the assistance graphic
When Blind Spot Assist is activated, gray radar
waves propagating backwards appear next to
the vehicle in the assistance display in the mul-
tifunction display (
Ypage 221). Above a speed
of 20 mph (30 km/h), the color of the radar
waves in the assistance graphic changes to
green :. Blind Spot Assist is then ready for use.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in front of
your vehicle by means of multifunction cam-
era:which is attached behind the top of the
windshield. Active Lane Keeping Assist detects
lane markings on the road and can warn you
before you leave your lane unintentionally.
This function is available in the range between
40 mph and 120 mph (60 km/h and 200 km/h).
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.
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Important safety notes
GWARNING
Lane Keepin g Assist cannot always clearly
detect lane markings.
In such cases, Lane Keepin g Assist can:
Rgive an unnecessary warning
Rnot give a warning
There isa risk of an acc ident.
Always pay particular attention to the traff ic
situation and keep within the lane, especial ly
if Lane Keepin g Assist alerts you.
GWARNING
The Lane Keepin g Assist warning does not
return the veh icleto the original lane. There is
a risk of an acc ident.
You should always steer, brake or accelerate
yourself, inparticular ifwarned byLane Keep-
ing Assist.
Lane Keepin g Assist can neither reduce the risk
of an acc identif you fail to adapt your driving
style nor overr idethe laws of physics. Lane
Keepin g Assist cannot take into account the
road, traff icand weather conditions. Lane Keep-
ing Assist ismerely an aid.You are responsible
for the distance to the veh icle infront, for veh i-
cle speed, for braking ingood time and for stay-
ing inyour lane.
The Lane Keepin g Assist does not keep the veh i-
cle inthe lane.
The system may beimpaired or may not function
if:
Rthere ispoor vis ibility, e.g. due to insuff icient
illumi nation of the road, or due to snow, rain,
fog or spray
Rthere isglare, e.g. from oncoming traffic, the
sun or reflection from other veh icles (e.g. if
the road surface iswet)
Rthe windshield is dirty, fogged up, damaged or
covered, for instance bya sticker, inthe vicin-
ity of the camera
Rthere are no, several or unclear lane markings
for a lane, e.g. inareas with road construction
work
Rthe lane markings are worn away, dark or cov-
ered up, e.g. by dirtor snow
Rthe distance to the vehicle infront is too small
and the lane markings thus cannot be detec-
ted
Rthe lane markings change quickly, e.g. lanes
branch off, cross one another or merge
Rthe road isnarrow and winding
Rthere are highly variable shade conditions on
the roadway
Activating/deactivating Lane Keeping
Assist
XTo activate: press button ;.
In dicator lamp :lights up. The Lane Keep‐
ingAssistOnmessage appears in the mul-
tifunction display. If all conditions have been
satisfied, there may be a warning.
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
the lines inthe assistance graphics display
(
Ypage 221) are shown in green. Lane Keep-
ing Assist is ready for use.
XTo deactivate: press button;.
Indicator lamp :goes out. Lane Keeping
Assist is deactivate d.The Lane Keeping
Assist Offmessage appears inthe multi-
function display.
Selecting Standard or Adaptive setting
XIn the DriveAssistmenu on the on-board
computer, select the LaneKeepingAssistfunction (Ypage 223).
XSelectStandardorAdaptive.
Standard
When Standard
is selected, no warning vibra-
tion occurs if:
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Ryou switch on thetur nsignals. In this event ,
th ewarnings are suppressed for acertain
period of time.
Ra drivin gsafet ysystem intervenes, e.g. ABS,
BA Sor ES P®.
Adaptive
Whe nAdaptive
is selected, no warnin gvibra-
tion occur sif:
Ryou switch on th etur nsignals. In this event ,
th ewarnings are suppressed for acertain
period of time.
Ra drivin gsafet ysystem intervenes, e.g. ABS,
BA Sor ES P®.
Ryou accelerate hard, e.g. kickdown .
Ryou brakehard.
Ryou steer actively, e.g. swerve to avoid an
obstacle or chang elanes quickly.
Ryou cut th ecorner on ashar pbend.
In order that you are warned only when neces-
sar yand in goo dtime if you cross th elan emark-
ing, th esystem recognizes certain condition s
and warn syou accordingly.
The warnin gvibration occur searlier if:
Ryou approac hth eouter lan emarking on a
bend.
Rth eroa dhas ver ywide lanes, e.g. afreeway.
Rth esystem detects soli dlan emarkings.
The warnin gvibration occur slater if:
Rth eroa dhas narrow lanes
Ryou cut th ecorner on aben d
Driving Assistance PLUS package
Gene ral notes
The Drivin gAssistance Plus packag econsist sof
Distanc ePilo tDISTRONI C (Ypage 171), Active
Blind Spot Assis t (Ypage 204) and Active Lan e
Keepin gAssis t (Ypage 207).
Active Blind Spot Assist
Generalnotes
Active Blind Spot Assis tuses arada rsensor
system, pointe dtoward th erear of th evehicle,
to monitor th earea to th eside sof th evehicl e
whic hth edriver is unable to see . Awarnin glamp
lights up in th eexterio rmirror sand draw syour
attention to vehicles detecte din th emonitore darea
.If you then switch on th ecorrespondin g
tur nsignal to chang elane, you will also receiv e
an optica land audibl ewarning. If aris kof lateral
collision is detected, corrective brakin gmay
help you avoid acollision .Befor e acourse-cor-
recting brak eapplication ,Active Blind Spot
Assis tevaluates th espac ein th edirection of
travel and at th eside sof th evehicle. Fo rthis,
Active Blind Spot Assis tuses th eforward-facing
rada rsensors.
Active Blind Spot Assis tsupport syou from a
speed of approximately 20 mph (30 km/h).
Important safety notes
Active Blind Spot Assist isonly an aid and is not
a substitute for attentive driving.
GWARNING
Active Blind Spot Assist does not react to:
Rvehicles overtaken too closely on the side,
placing them in the blind spot area
Rvehicles which approach with a large speed
differential and overtake your vehicle
As a result, Active Blind Spot Assist may ne i-
ther give warnings nor intervene insuch sit-
uations. There isa risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
iUSA only: This device has been approved by
the FCC as a "Vehicular Radar System". The
radar sensor is intended for use inan auto-
motive radar system only. Removal, tamper-
ing, or altering of the device willvoid any war-
ranties, and isnot permitted by the FCC. Do
not tamper with, alter, or use inany non-
approved way.
Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
iCanada 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 an
y warranties, and is not permitte
d.
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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.
Radar sensors
The Active Blind Spot Assist radar sensors are
integrated into the front and rear bumpers and
behind a cover in the radiator trim. 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.
Monitoring area
GWARNING
Active Blind Spot Assist does not detect all
traffic situations and road users. There is a
risk of an accident.
Always make sure that there is sufficient dis-
tance on the side for other traffic or obstacles.
At a distance of approximately 1.6 ft (0.5 m);
from the vehicle, Active Blind Spot Assist mon-
itors the area up to 10 ft (3 m) next to =and
behind :your vehicle, as shown in the picture. The detection of obstacles can be impaired in
the case of:
Rthere is dirt on the sensors or anything else
covering the sensors
Rpoor visibility, e.g. due to rain, snow or spray
Vehicles in the monitoring range are then not
indicated.
Active Blind Spot Assist may not detect narrow
vehicles, such as motorcycles or bicycles, or
may only detect them too late.
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 driv-
ing 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:
Rwarnings may be issued in error when driving
close to crash barriers or similar solid lane
borders.
Rwarnings may be interrupted when you are
driving alongside particularly long vehicles,
such as trucks, for a prolonged time.
Warning lamp
:Warning lamp
Active Blind Spot Assist is not operational at
speeds below approximately 20 mph (30 km/h).
Vehicles in the monitoring range are then not
indicated.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp :on the correspond-
ing 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).
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If you select the reverse gear, Active Blind Spot
Assist is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
When Active Blind Spot Assist is activated, gray
radar waves propagating backward appear next
to the vehicle in the assistance display in the
multifunction display. Above a speed of 20 mph
(30 km/h), the color of the radar waves in the
assistance display changes to green;. Active
Blind Spot Assist is then ready for use.
Visual and acoustic collision warning
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 will then hear a double warning
tone and red warning lamp :flashes. If the turn
signal remains on, detected vehicles are indica-
ted 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 a lat-
eral collision in the monitoring range, a course-
correcting brake application is carried out. This
is meant to assist you in avoiding a collision.
GWARNING
A course-correcting brake application cannot always prevent a collision. There is a risk of an
accident.
Always steer, brake or accelerate yourself,
especially if Active Blind Spot Assist warns
you or makes a course-correcting brake appli-
cation. Always maintain a safe distance at the
sides. If a course-correcting brake application occurs,
red warning lamp
:flashes in the exterior mir-
ror and a double warning tone sounds. In addi-
tion, a display underlining the danger of a side
collision appears in the multifunction display.
In very rare cases, the system may make an
inappropriate brake application. A course-cor-
recting brake application may be interrupted at
any time by countersteering slightly or acceler-
ating.
The course-correcting brake application is avail-
able in the speed range between 20 mph
(30 km/h) and 120 mph (200 km/h).
Either no braking application, or a course-cor-
recting brake application adapted to the driving situation occurs if:
Rthere are vehicles or obstacles, e.g. crash
barriers, located on both sides of your vehicle.
Ra vehicle approaches you too closely at the
side.
Ryou have adopted a sporty driving style with
high cornering speeds.
Ryou clearly brake or accelerate.
Ra driving safety system intervenes, e.g. ESP®
or PRE-SAFE®Brake.
RESP®is switched off.
Ra loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist
XMake sure that Active Blind Spot Assist is
activated in the on-board computer
(
Ypage 223).
XSwitch on the ignition.
Warning lamps :in the exterior mirrors light
up red for approximately 1.5 seconds.
Gray radar waves propagating backwards
appear next to the vehicle in the assistance
graphic in the multifunction display ;.
Above a speed of 20 mph (30 km/h), the color
of the radar waves in the assistance display
changes to green ;. Active Blind Spot Assist
is then ready for use.
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