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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.
Activating Blind Spot Assist
XMake sure that Blind Spot Assist is activated
in the on-board computer (Ypage 232).
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 231). 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.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection.
This can be accomplished by checking the trailer
lighting. In this event, Blind Spot Assist is deac-
tivated. The Blind
SpotAssistNotAvail‐able When Towing a Trailer See Opera‐tor's Manualmessage appears in the multi-
function display.
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.
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This function is available in the range between
40 mph and 120 mph (60 km/hand 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.
Important safety notes
GWARNING
Lane Keeping Assist cannot always clearly
detect lane markings.
In such cases, Lane Keeping Assist can:
Rgive an unnecessary warning
Rnot give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Lane Keeping Assist alerts you.
GWARNING
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 Keep-
ing Assist.
Lane Keeping Assist can neither reduce the risk of an accident if you fail to adapt your driving
style nor override the laws of physics. Lane
Keeping Assist cannot take into account the
road, traffic and weather conditions. Lane Keep-
ing Assist is merely an aid. You are responsible
for the distance to the vehicle in front, for vehi-
cle speed, for braking in good time and for stay-
ing in your lane.
The Lane Keeping Assist does not keep the vehi-
cle in the lane.
The system may be impaired or may not function
if:
Rthere is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,
fog or spray
Rthere is glare, e.g. from oncoming traffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet)
Rthe windshield is dirty, fogged up, damaged or
covered, for instance by a sticker, in the vicin-
ity of the camera
Rthere are no, several or unclear lane markings
for a lane, e.g. in areas with road construction
work
Rthe lane markings are worn away, dark or cov-
ered up, e.g. by dirt or snow
Rthe distance to the vehicle in front 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 is narrow and winding
Rthere are highly variable shade conditions on the roadway
Activating/deactivating Lane Keeping
Assist
XTo activate: press button ;.
Indicator 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 in the assistance graphics display
(
Ypage 231) are shown in green. Lane Keep-
ing Assist is ready for use.
XTo deactivate: press button;.
Indicator lamp :goes out. Lane Keeping
Assist is deactivated. The Lane Keeping
Assist Offmessage appears in the multi-
function display.
Selecting Standard or Adaptive setting
XIn the DriveAssistmenu on the on-board
computer, select the LaneKeepingAssistfunction (Ypage 233).
XSelectStandardorAdaptive.
Standard
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WhenStandardis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Ra driving safety system intervenes, e.g. ABS,
BAS or ESP®.
Adaptive
When Adaptive
is selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Ra driving safety system intervenes, e.g. ABS,
BAS or ESP®.
Ryou accelerate hard, e.g. kickdown.
Ryou brake hard.
Ryou steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
Ryou cut the corner on a sharp bend.
In order that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, the system recognizes certain conditions
and warns you accordingly.
The warning vibration occurs earlier if:
Ryou approach the outer lane marking on a
bend.
Rthe road has very wide lanes, e.g. a freeway.
Rthe system detects solid lane markings.
The warning vibration occurs later if:
Rthe road has narrow lanes
Ryou cut the corner on a bend
Driving Assistance Plus package
General notes
The Driving Assistance Plus package consists of
Distance Pilot DISTRONIC (Ypage 170), Active
Blind Spot Assist (Ypage 209) and Active Lane
Keeping Assist (Ypage 212).
Active Blind Spot Assist
General notes
Active Blind Spot Assist uses a radar sensor
system, pointed toward the rear of the vehicle,
to monitor the area to the sides of the vehicle
which the driver is unable to see. 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. If a risk of lateral
collision is detected, corrective braking may
help you avoid a collision. Before a course-cor-
recting brake application, Active Blind Spot
Assist evaluates the space in the direction of
travel and at the sides of the vehicle. For this,
Active Blind Spot Assist uses the forward-facing
radar sensors.
Active Blind Spot Assist supports you from a
speed of approximately 20 mph (30 km/
h).
Important safety notes
Active Blind Spot Assist is only 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 is a 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 will void any war-
ranties, and is not permitted by the FCC. Do
not tamper with, alter, or use inany non-
appr oved 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
rec eived, including interference that may
cause undesired operation of the device.
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Removal, tampering,or altering of th edevice
will voi dany warranties, and is no tpermitted.
Do no ttamper with, alter, or use in any non-
approve dway.
An yunauthorized modification to this device
could voi dth euser's authority to operate th e
equipment.
Rada rsensors
The Active Blind Spot Assist radar sensor sare
integrate dint oth efron tand rear bumpers and
behind acover in th eradiato rtrim. Mak esur e
that th ebumpers and th ecover in th eradiato r
grill are free of dirt ,ice or slush. The rear sensor s
mus tno tbe covered, for exampl eby cycle racks
or overhanging cargo. Followin g asevere impact
or in th eevent of damag eto th ebumpers ,hav e
th efunction of th eradar sensor schecke dat a
qualified specialist workshop. Active Blind Spot
Assist may otherwise no longer wor kproperly.
Monitoring area
GWARNIN G
Active Blind Spot Assist does no tdetec tall
traffic situation sand road users. There is a
ris kof an accident.
Always mak esur ethat there is sufficien tdis-
tance on th eside for other traffic or obstacles.
At adistanc eof approximately 1. 6ft (0. 5m) ;
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 232).
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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Active Lane Keeping Assist
Generalnotes
Active Lan eKeepin gAssis tmonitors th earea in
fron tof your vehicl eby mean sof multifunction
camera :at th eto pof th ewindshield. Various
differen tareas to th efront, rear and side of your
vehicl eare also monitore dwit hth eaid of th e
radar sensor system. Active Lan eKeepin g
Assis tdetects lan emarking son th eroad and
can warn you before you leav eyour lan eunin-
tentionally. If you do no treac tto th ewarning , a
lane-correcting application of th ebrakes can
bring th evehicl ebac kint oth eoriginal lane.
This function is available in th erange between
40 mph and 12 0mph (60 km/h and 20 0km/h).
Important safety notes
If you fail to adapt your drivin gstyle, Active Lan e
Keepin gAssis tcan neither reduce th eris kof an
acciden tno roverride th elaws of physics .Active
Lan eKeepin gAssis tcanno ttak eaccoun tof
road and weather conditions. It may no trecog-
niz etraffic situations. Active Lan eKeepin g
Assis tis only an aid. You are responsibl efor th e
distanc eto th evehicl ein front, for vehicl e
speed, for braking in goo dtime and for stayin gin
your lane.
Active Lan eKeepin gAssis tcanno tcontinuously
keep your vehicl ein it slane.
GWARNIN G
Active Lan eKeepin gAssis tcanno talways
clearly detec tlan emarkings.
In suc hcases, Active Lan eKeepin gAssis t
can :
Rgivean unnecessary warning and then
mak e acourse-correcting brak eapplication
to th evehicl e
Rnotgiv e a warning or interven e
There is aris kof an accident.
Always pay particular attention to th etraffic
situation and keep within th elane, especially
if Active Lan eKeepin gAssis talerts you. Ter -
minate th eintervention in anon-critical driv-
ing situation .
The system may be impaire dor may no tfunction
if:
Rthere is poor visibility, e.g. due to insufficien t
illumination of th eroad ,or due to snow, rain ,
fog or heav yspray
Rthere is glare, e.g. from oncomin gtraffic, th e
sun or reflection from other vehicles (e.g. if
th eroad surfac eis wet )
Rthewindshield is dirty, fogged up, damaged or
covered, for instance by asticker, in th evicin-
it y of th ecamera
Rth eradar sensor sin th efron tor rear bumpers
or th eradiato rtrim are dirty, e.g. obscured by
snow
Rthere are no or several unclear lan emarking s
for on elane, e.g. roadworks
Rth elan emarking sare wor naway, dark or cov-
ere dup, e.g. by dir tor snow
Rth edistanc eto th evehicl ein fron tis to oshort
and thus thelan emarking scanno tbe detec -
te d
Rth elan emarking schang equickly, e.g. lanes
branch off ,cross on eanother or merge
Rth eroad is narrow and windin g
Rthere are highly variable shad econdition son
th eroadway
If no vehicl eis detecte din th eadjacent lan eand
broke nlan emarking sare detected, no lane-cor-
recting brak eapplication is made .
Warning vibration in th esteering wheel
A warning may be given if afron twhee lpasses
ove r alan emarking .It will warn you by mean sof
intermittent vibration in th esteering whee lfor
up to 1. 5seconds.
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Lane-correcting brake application
If you leave your lane, under certain circumstan-
ces the vehicle will brake briefly on one side.
This is meant to assist you in bringing the vehicle
back to the original lane.
GWARNING
A lane-correcting brake application cannot
always bring the vehicle back into the original lane. There is a risk of an accident.
Always steer, brake or accelerate yourself,
especially if Active Lane Keeping Assist warns
you or makes a lane-correcting brake appli-
cation.
If a lane-correcting brake application occurs,
display :appears in the multifunction display.
The brake application also slightly reduces vehi-
cle speed.
A lane-correcting brake application can be made
after driving over a lane marking recognized as
being solid or broken. 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 have been
detected.
In the case of a broken lane marking being
detected, a lane-correcting brake application
can only be made if a vehicle has been detected
in the adjacent lane. Oncoming vehicles, over-
taking vehicles and vehicles in adjacent lanes
can be detected.
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:
Ryou clearly and actively steer, brake or accel-
erate.
Ryou cut the corner on a sharp bend
Ryou have switched on the turn signal
Ra driving safety system intervenes, e.g. ESP®,
PRE-SAFE®Brake or Active Blind Spot Assist
Ryou have adopted a sporty driving style with
high cornering speeds or high rates of accel-
eration
RESP®is switched off
Rthe transmission is not in position h.
Ron vehicles with a trailer tow hitch, the elec-
trical connection to the trailer has been cor-
rect
ly established
Ra loss of tire pressure or a defective tire has
been detected and displayed.
Ran obstacle has been detected in the lane in
which you are driving
Active Lane Keeping Assist may not detect other
road users or traffic situations. An inappropriate
brake application may be interrupted at any time
if you:
Rsteer slightly in the opposite direction
Rswitch on the turn signal
Ryou brake or accelerate significantly.
A lane-correcting brake application is interrup-
ted automatically if:
Ra driving safety system intervenes, e.g. ESP®,
PRE-SAFE®Brake or Active Blind Spot Assist
Rlane markings are no longer detected
Activating/deactivating Active Lane
Keeping Assist
XTo activate: press button ;.
Indicator lamp :lights up. The Lane Keep‐
ingAssistOnmessage appears in the mul-
tifunction display. If all conditions have been
satisfied, a warning or steering intervention
may be made.
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
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the lines on the assistance graphic display are
shown in green (Ypage 231). Active Lane
Keeping Assist is ready for use.
XTo deactivate: press button;.
Indicator lamp :goes out. The Active Lane
Keeping Assist is deactivated. The Lane
Keeping Assist Offmessage appears in
the multifunction display.
Selecting Standard or Adaptive setting
XIn the DriveAssistmenu on the on-board
computer, select the Active Lane Keep‐
ing Assistfunction (Ypage 233).
XSelect settingStandardorAdaptive.
When Standardis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time
Ra driving safety system intervenes, such as
ABS, BAS or ESP®
When Adaptiveis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event, the warnings are suppressed for a certain
period of time.
Ra driving safety system intervenes, e.g.
ABS, BAS or ESP®
Ryou accelerate hard, e.g. kickdown.
Ryou brake hard
Ryou steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly
Ryou cut the corner on a sharp bend
To ensure that you are warned only when nec-
essary and in good time if you cross the lane
markings, the system detects certain conditions
and warns you accordingly.
The warning vibration occurs earlier if:
Ryou approach the outer lane marking on a
bend
Rthe road has very wide lanes, e.g. a freeway
Rthe system detects solid lane markings
The warning vibration occurs later if:
Rthe road has narrow lanes
Ryou cut the corner on a bend
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection. This can be accomplished by checking the trailer
lighting.
Towing a trailer
Important safety notes
GWARNING
Installing an unsuitable ball coupling may
result in overloading of the trailer tow hitch
and the rear axle. This applies especially if the ball coupling in question is longer or angled
differently. This could seriously impair the
driving characteristics and the trailer can
come loose. There is a risk of an accident.
You should only ever install a ball coupling
that has the permissible dimensions and that
is designed to meet your trailer-towing
requirements. Do not modify the ball coupling
or the trailer tow hitch.
You will find the values approved by the manu-
facturer on the vehicle identification plates and
those for the towing vehicle under "Technical
data" (
Ypage 384).
GWARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi- cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary.
!If you have a trailer tow hitch retrofitted,
changes to the engine cooling system may be
necessary, depending on the vehicle type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
The installation of a trailer tow hitch is only per-
missible if a towing weight is specified in your
vehicle documents. If this is not the case, then
the vehicle is not approved for the towing of a
trailer.
214Towing a trailer
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