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RESP®intervenes or youdeactivate ESP®
Rthere is amalfunctio ninthe ESP®or ABS sys-
tem
If cruis econtro lautomaticall ydeactivates, a
warning tone sounds and the Cruise
ControlOffmessage appearsbriefl yint he display.
The V symbo land the displa yofthe stored
spee dint he header or in the status area of the
displa yarethenn ot shown.
Problems with cruis econtrol
The spee dcanno tbes et when cruis econtro lis
activated.
The displa yisshowing amessage of high priority
and canno ttherefore sho wachange in speed.
XProcee dasinstructed by the message in the
display.
COLLISIO NPREVENTION ASSIST
General notes
COLLISION PREVENTION ASSIST help syou:
Rto minimize the ris kofafront-end collision
with adetecte dobstacle in the path of your
vehicle
Rto reduce the consequences of afront-end
collision
The system uses rada rsensor stod etect vehi-
cle sinf ront.
COLLISION PREVENTION ASSIST consists of the
distance warning functio nand Adaptive Brake
Assist.
If COLLISION PREVENTION ASSIST is malfunc-
tioning ,the displa yshows acorresponding mes-
sage (
Ypage 213).
Distance warning function
Important safety notes
GWARNING
The distance warning functio ndoesn ot react:
Rto people or animals
Rto oncomin gvehicles
Rto crossing traffic
Rwhen cornering
Thus, the distance warning functio ncannot
provid eawarning in al lcritica lsituations.
There is ariskofana ccident.
Alway spaycarefu lattentio ntothe traffics it-
uatio nand be ready to brake.
GWARNING
The distance warning functio ncanno talway s
clearly identify objects and comple xtraffic
situations.
In such cases, the distance warning function
may:
Rgive an unnecessary warning
Rnot give awarning
There is ariskofana ccident.
Alway spaycarefu lattentio ntothe traffics it-
uatio nand do not rel ysolel yont he distance
warning function.
In particular ,the detection of obstacle scan be
impaired in the cas eof:
Rdirt on the sensor soranything else covering
the sensors
Rit is snowing or raining heavily
Rthere is interferenc efromo therradar sources
Rthe possibility of strong rada rreflections, for
example, in parkin ggarages .
Ranarrow vehicl etraveling in front, e.g .a
motorbike
Rav ehicl etraveling in front on adifferent line
Due to the nature of the system ,particularly
complicate dbutnon-critical drivin gconditions
maya lsoc ause the system to displa yawarning.
If yo ufailtoa dapt your drivin gstyle ,the dis-
tance warning functio ncan neitherr educe the
ris kofana ccident nor override the laws of phys-
ics .The distance warning functio ncanno ttake
into account road, weather or trafficc onditions.
The distance warning functio ni
so nlyana id.
You
ar er esponsibl efor the distance to the vehicl ein
front, for vehicl espeed, braking in good time
and for staying in your lane.
Following damage to the front end of the vehicle,
have the configuratio nand operatio nofthe
rada rsensor checked at aquali fied specialist
workshop .Thisa lsoa pplies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.
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If you change wheel size, make sure they corre-
spond to the correct wheel size category
(
Ypage 267). If the category is changed without
recoding the control units in the vehicle,t he
functioning of the distance warning feature may
be impaired. COLLISION PREVENTION ASSIST
may then detect amalfunction and switch itself
off.
Operation
XTo activate/deactivate: activate or deacti-
vate the distance warning function in the on-
board computer (
Ypage 184).
If the distance warning function of the COL-
LISION PREVENTION ASSISTisa ctivated, the
display shows the Äsymbol:
Rin the header
Rin the Status Overviewof the Assist.menu (Ypage 183)
At speedsuptoa pprox20m ph (30 km/h) the
display in vehiclesw ith Active Parking Assist
first shows the ístatus indicator. Only from
as peed of abou t20m ph (30 km/h )does the
display show the Äsymbolinstead of the
í status indicator.
The distance warning function can help you to
minimize the risk of afront-end collision with a
vehicle ahea dorreduce the effects of such a
collision. With the help of the rada rsensor sys-
tem, the distance warning function can detect
obstacles that are in the path of you rvehicle for
an extended period of time. If the distance warn-
ing function detects that there is arisk of acol-
lision, you wil lbewarned visually and, where
necessary ,acoustically.W ithout yourinterven-
tion, the distance warning function cannot pre-
vent acollision.
The distance warning function issues awarning
at speeds:
Rfrom abou t4mph (7 km/h) if you approach a
vehicle traveling in front or astationary vehi-
cle very quickly. The ·warning lamp in the
instrument cluster flashe sand an intermittent
warning tone also sounds.
At speedsuptoa bout45mph (70 km/h), the
system also detects stationary obstacles ,for
example stationary or parked vehicles.
XBrake immediately until the distance to the
obstacle increases and the risk of acollision
has passed.
or
XTake evasive action, provideditiss afe to do
so.
Adaptive Brake Assist
General notes
Adaptive Brake Assist evaluates the traffic sit-
uatio nwith the help of the rada rsensor system
and can detect obstacle swhich have been in
you rvehicle's path for an extended period of
time. From speedsa bove4mph (7 km/h), Adap-
tive Brake Assist aid syou in braking during haz-
ardou ssituations.
Up to aspeed of approximately 125 mph
(200 km/h), Adaptive Brake Assist is capable of
reacting to moving obstacle sthat have already
been detected as such at least once over the
period of observation.
Important safety notes
GWARNING
Adaptive Brake Assist does not react:
Rto peopleora nimals
Rto oncoming vehicles
Rto crossing traffic
Rto stationary obstacles
Rwhen cornering
As aresult, the Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Alway spay careful attention to the traffic sit-
uatio nand be ready to brake.
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can:
Rintervene unnecessarily
Rnot intervene
There is arisk of an accident.
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Alwayspaycarefu lattentio ntothe traffic sit-
uatio nand be ready to brake. Terminate the
interventio ninanon-critica ldriving situation.
In particular, the detection of obstacle scan be
impaired in the cas eof:
Rdirt on the sensors or anything else covering
the sensors
Rsnow or heavy rain
Rinterference from othe rradar sources
Rstrong rada rreflections, for example, in park-
ing garages
Ran arrow vehicl etraveling in front, e.g .a
motorbike
Rav ehicl etraveling in front on adifferent line
Due to the nature of the system ,particularly
complicate dbutnon-critica ldriving conditions
maya lsoc ause Adaptive Brake Assist to inter-
vene.
If yo ufailtoa dapt your driving style ,Adaptive
Brake Assist can neither reduce the ris kofacci-
dent nor override the laws of physics. Adaptive
Brake Assist canno ttake into account road,
weather or traffic conditions. Adaptive Brake
Assist is onlyana id.Y ou arer esponsibl efor the
distance to the vehicl einfront, for vehicle
speed ,braking in goo dtime and for staying in
your lane.
Following damage to the front end of the vehicle,
have the configuratio nand operatio nofthe
rada rsensor checked at aquali fied specialist
workshop.T hisa lsoa pplies to collisions at slow
speed swhe
re the rei
snov isible damage to the
front of the vehicle.
If yo uchange whee lsize, make sure they corre-
spond to the correct whee lsizec ategory
(
Ypage 267). If the categor yischangedw ithout
recoding the contro lunits in the vehicle, the
functioning of Adaptive Brake Assist mayb e
impaired .COL LISION PREVENTION ASSIST may
then detect amalfunctio nand switch itsel foff.
If Adaptive Brake Assist is not availabl edueto a
malfunctio ninthe rada rsensor system ,the
brake system remains availabl ewithf ullb rake
boosting effect and BAS.
Operation
With the hel pofthe rada rsensor system ,Adap-
tive Brake Assist can detect obstacle sthath ave
been in the path of your vehicl efor an extended
perio doft ime.Adaptive Brake Assist does not
react to stationar yobstacles. If Adaptive Brake Assist detects
ariskofc ollision with avehicle
traveling in front or with astationar yobstacle,
the system calculate sthe braking forc eneces-
sary to avoidt hiscollision. If yo uapply the
brakes forcefully, Adaptive Brake Assist will
automaticall yincrease the braking forc etoa
level suitabl efor the traffic conditions.
XBrake unti lthe distance to the obstacle
increases and the ris kofacollision passes.
ABS
prevents the wheels from locking.
The brakes functio nasusual againif:
Ryour elease the brake pedal
Rther eisnol ongera ny dangerofac ollision
Rno obstacle is detecte dinfront of your vehicle
Braking assistance is then ended.
Blind SpotA ssist
General notes
Blind Spo tAssist monitors the area soneither
side of the vehicl ethata renot visible to the
driver with two lateral, rear-facing rada rsensors
in the bumper. It supports yo ufrom speed sof
approximately20m ph (30 km/h).Awarning
display in the exterio rmirrors draws your atten-
tio ntov ehicles detecte dinthe monitore darea.
If yo uthen switch on the corresponding turn
signaltoc hange lane, yo uwilla lsor eceive an
optica land audibl ecollision warning.
Important safety notes
GWARNING
Blind Spo tAssist does not react to:
Rvehicles overtake ntoo closel yonthe side,
placing them in the blind spo tarea
Rvehicles which approach with alarge speed
differential and overtake your vehicle
As aresult, Blind Spo tAssist mayn ot give
warning sinsuchs ituations. There is arisko f
an accident.
Alway sobserve the traffic conditions care-
fully, and maintain asafel atera ldistance.
Blind Spo tAssist is onlyana id.Itm ayfailto
detect som evehicles and is no substitute for
attentive driving .Alway sensure thatt hereis
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sufficient distance to the side for other road
users and obstacles.
In particular, the detection of obstacles can be
impaired in the case of:
Rdirt on the sensors or anything else covering
the sensors
Rfog, heavy rain or snow
Rnarrow vehicles, e.g. motorcycles or bicycles
Rvery wide lanes
Rnarrow lanes
Rvehicles not driving in the middle of their lane
Rbarriers or other road boundaries
Vehicles in the monitoring range are then not
indicated.
iUSA only:
This device has been approved by the FCC as
a" Vehicular Rada rSystem". 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.
Monitoring range of the sensors
Blind Spot Assist monitors the area shown in the
diagramupt o118 in (3 m) behind and directly
next to your vehicle.
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 the vehicles are driving on the inner side
of their lane.
Due to the nature of the system:
Rwarnings may be issued in error when driving
close to crash barriers or similars olid lane
borders.
Rwarnings may be interrupted when driving
alongside long vehicles, for example trucks,
for aprolonged time
The two sensors for Blind Spot Assist are inte-
grated into the sides of the rear bumper. Make
sure that the bumper is free of dirt, ice or slush
in the vicinity of the sensors. The radar sensors
must not be covered, for example by rear-moun-
ted cycle racks or overhanging loads. Following
as evere impact or in the event of damage to the
bumper, have the function of the radar sensors
checked at aqualified specialist workshop.
Blind Spot Assist may otherwise not work prop-
erly.
Warning display
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 av ehicle is detected within the monitoring
range of Blind Spot Assist at speeds above
approximately 20 mph (30 km/h), warning
lamp :lights up red in the exterior mirror on
the corresponding side. Warning lamp :
always lights up when avehicle enters the blind
spot monitoring range from behind or from the
side. When you overtake avehicle, the warning
only occurs if the difference in speed is less than
7m ph (11 km/h).
If you select reverse gear, Blind Spot Assist is
inactive.
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The intensity of warning lamps:depends on
the brightness of the ambient light and is con-
trolled automatically.
Collision warning
If av ehicle is detected in the monitoring range of
Blind Spot Assist and you switch on the corre-
sponding turn signal, adouble warning tone
sounds once. The warning lamp in the corre-
sponding exterior mirror flashes. If the turn sig-
nal remains on, detected vehicles are indicated
by the flashing of the warning lamp in 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 184).
XTurn the key to position 2in the ignition lock.
The warning lamps in the exterior mirrors light
up for approximately 1.5 seconds.
Status indicators in the status overview submenu
If Blind Spot Assist is activated, the display
shows symbol :in the StatusOverviewsub-
menu of the on-board computer (Ypage 183). If
you are driving faster than 20 mph (30 km/h) ,
the symbo lalsos hows rada rwaves between the
two vehicles ;.Blind Spo tAssist is thenr eady
for use.
Towin gatrailer
If youattach atrailer, make sure thaty ouhave
correctl yestablishe dthe electrical connection.
Thi scan be accomplishe dbychecking the trailer
lighting. Blind Spo tAssist is thend eactivated
and the Blind Spo tAssist Currently
Unavail. See Operator' sManualmessage
appear sinthe display.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in front of
your vehicl ebymeans of camera :which is
mounted at the top of the windshield. Lane
Keeping Assist detects lane markings on the
roa dand can warn yo ubefor ey ou leav eyour
lane unintentionally.
This functio nisa vailable in the range between
40 mph (60 km/h )and 125 mph (20 0km/h).
Aw arning maybeg iven if afront whee lpasses
ove ralanem arking. It will warn yo ubymeans of
intermittent vibratio nthroug hthe steering
whee lfor up to 1.5 second s.
Importan tsafety notes
GWARNING
Lane Keeping Assist may not always clearly
recognize lane markings.
In this case, Lane Keeping Assist may:
Rgive an unnecessary warning
Rnot give awarning
There is ariskofana ccident.
Alway spayparticula rattention to the traffic
situation and stay in lane, in particula rif
warned by Lane Keeping Assist.
GWARNING
The Lane Keeping Assist warning doe snot
return the vehicl etothe original lane. There is
ar iskofana ccident.
Yo us houl dalway ssteer, brake or accelerate
yourself, in particula rifwarned by Lane Keep-
ing Assist.
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If you fail to adapt yourdriving style, Lane Keep-
ing Assist can neither reduce the risk of accident
nor override the law sofphysics. Lane Keeping
Assist cannot take into account road, weather or
traffic conditions. Lane Keeping Assist is only an aid .You are responsible for the distance to the
vehicle in front, for vehicle speed,b raking in
good time and for staying in you rlane.
Lane Keeping Assist does not keep you rvehicle
in its lane.
The system may be impaired or may not function
if:
Rthere is poor visibility, e.g. due to insufficient
illuminatio nofthe 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 asticker, in the vicin-
ity of the camera
Rno, or several ,unclea rlane markings are pres-
ent for one lane, e.g. in aconstruction area
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 highlyv ariable shade conditions on
the road
Deactivating and activating Lane Keep-
ing Assist
XPress the Çbutton.
If the indicator lamp in the button lights up
and the display shows the Çsymbo linthe status area
,Lane Keeping Assist is switched
on but not ready for use.
If you drive at speedsa bove 40 mph
(60 km/h) and lane markings are detected,
the display shows the highlighted Çsym-
bol in the status area when Lane Keeping
Assist is activated. Lane Keeping Assist is
then ready for use.
Status indicators in the status overview submenu
The display in the Status Overviewsubmenu
of the on-board computer also shows the status
of Lane Keeping Assist (
Ypage 183). If Lane
Keeping Assist is activated but not ready for use,
the display shows the boundary lines in the sym-
bol as dashed :.IfLane Keeping Assist is ready
for use, the boundary lines in the symbo lare
shown as solid lines ;.
Setting the sensitivity of Lane Keeping
Assist
XIn theAssist.menu on the on-board com-
puter, select the Lane Keeping Assist:
function (Ypage 184).
XSelectStandardorAdaptive.
In the setting Standard
,now arning vibration
occurs if:
Ryou operate the turn signal in the correspond-
ing direction. In this event, the warnings are
suppressed for acertain period of time.
Rad riving safety system, such as ABS, BAS or
ESP®,i ntervenes or performs acontrol
action.
When Adaptive
is selected, there is also no
warning vibratio nwhen:
Ryou accelerate hard, e.g. kickdown.
Rbrake sharply
Ryou steer actively ,e.g. swerve to avoid an
obstacle or change lanes quickly.
Ryou cut the corner on asharp bend.
In order that you are warned only when neces-
sary and in good time if you cross the lane mark-
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ing, the system recognizes certain conditions
and warns you accordingly.
The warningvibration occurs earlier if:
Ryou approacht he outer lane marking on a
bend.
Rthe road has very wide lanes, e.g. afreeway.
Rthe system recognizes solid lane markings.
The warnin gvibration occurs later if:
Rthe road has narrow lanes.
Ryou cut the corner on abend.
Alertness Assistant ATTENTION
ASSIST
General notes
ATTENTIONA SSISTh elps you duringl ong,
monotonous journeys such as on freeways and
interstate highways. It is active in the 40 mph
(60 km/h) to 125 mph (200 km/h )range. If
ATTENTIONA SSISTd etect stypical indicator sof
fatigue or increasingl apses in concentration on
the part of the driver, it suggestst akingabreak.
Important safetyn otes
ATTENTIONASSISTiso nly an aid. The system
may not always detect fatigue or lapses in con-
centration until too late, or may not detect them
at all. ATTENTIONA SSISTisn otas ubstitut efor
aw ell-rested and attentive driver.
The functionality of ATTENTIONA SSISTi s
restricted, and warnings may be delayed or not
occur at all:
Rif the lengt hofthe journey is less than approx-
imately 30 minutes
Rif the road condition is poor, e.g. if the surface is uneven or if there are potholes
Rif there is astrong side wind
Rif you have adopte dasportyd rivings tyle with
high cornering speeds or high rate sofaccel-
eration
Rif you are predominantly drivingatas peed
below 40 mph (6 0km/ h)or above 125 mph
(200 km/h)
Rif the tim ehas been set incorrectly
Rin active drivings ituations,such as when you
change lanes or change your speed ATTENTIONA
SSISTisr eset and starts assessing
your attention again when you continue your
journey if:
Ryou switc hoff the engine
Ryou tak eoff your seat belt and open the driv-
er's door, e.g. for achange of drivers or to
tak eab reak
Displaying th eattention level
For vehicles with steeringw heel buttons you can
have the current ATTENTIONA SSIST( Attention
Level) assessmentd isplayed.
XSelectStatus Overviewin theAssist.menua nd display the attention level
(Ypage 183).
The followingi nformation is displayed:
Rthe lengthofthe journey sinc ethe last break
Rthe attention level determined by ATTENTION
ASSIST, displayed in abar display in five levels
froml ow to high
Rif ATTENTIONA SSISTisu nable to calculate
the attention level and cannot output awarn-
ing, the System
Passivemessage appears in
the display. The bar display is the ndimmed.
This is the case, for example, if you are pre-
dominantly drivingatas peed below 40 mph
(60 km/h) or above 125 mph (200 km/h).
Activating ATTENTION ASSIST
XActivatin gATTENTIONA SSISTw ith the on-
board computer:
Ron vehicles without steeringw heel buttons
(Ypage 174)
Ron vehicles with steeringw heel buttons
(Ypage 184)
For vehicles with steeringw heel buttons,the
system determines the attention level of the
driverd epending on the settin gselected:
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Standard:the sensitivity with which the sys-
tem determines the attention level is set to
normal.
Sensitive: the sensitivity is set higher. The
driver is warned earlier.
When ATTENTION ASSIST is switched on and
the vehicle engine is running:
Ron vehicles without steering wheel buttons,
the À indicator lamp in the instrument
cluster lights up
Ron vehicles with steering-wheel buttons, the
display shows the Àsymbol:
-in the status area
-in the Status Overviewof the Assist.menu (Ypage 183)
For vehicles with steering wheel buttons, if you
deactivate ATTENTION ASSIST, the system is
automatically re-activated when you start the
engine. The system sensitivity then corresponds to the last selection activated –standard or sen-
sitive.
If you switch off ATTENTION ASSIST in avehicle
without steering wheel buttons, the system
remains switched off even after you start the
engine. The status of the system after switching
on the engine always corresponds to the status
last selected.
Warning in the display
If the system detectst iredness or increasing
lapses in concentration, the warning Atten‐
tion Assist: TakeaBreak!orAttent.Asst: Take Break!is shown in the display.
An additional warning tone sounds.
XIf necessary, take abreak.
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. If you do not take
ab reak and ATTENTION ASSIST continues to
detect increasing lapses in concentration, you
will be warned again after 15 minutes at the
earliest. This will only happen if ATTEN-
TION ASSIST still detectst ypical indicators of
fatigue or increasing lapses in concentration.
PARKTRONIC
General notes
PARKTRONIC is an electronic parking aid. The
system is equipped with ultrasonic sensors in
the front and rear bumpers to monitor the area
around your vehicle. PARKTRONIC indicates vis-
uallya nd audibly the distance between your
vehicle and an object.
Your vehicle features two separate sound emit-
ters with different frequencies for the warning
tones. The warning ranges in front of and behind the vehicle are indicated by different warning
tones.
PARKTRONIC is activated automatically when
you:
Rturn the key to position 2in the ignition lock
Rrelease the parking brake and
Rmove the selector lever to D,Nor R
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h). PARKTRONIC is reactivated
at speeds below 10 mph (16 km/h).
Important safety notes
PARKTRONIC is only an aid. It cannot replace
your own awareness of the immediate surround-
ings. You are responsible for safe maneuvering,
parking and pulling away.W hen maneuvering,
parking and pulling away,m ake sure that there
are no persons, animals or object sinthe maneu-
vering area.
!Pay particular attention to obstacles above
or below the sensors when parking, such as
flower pots or trailer towbars. PARKTRONIC
does not recognizes uch objectswhen they
are in the immediate vicinity of the vehicle.
You could damage the vehicle or objects.
PARKTRONIC can suffer interference from:
Rultrasonic sources such as atruck's
compressed-air brakes, an automatic car
wash or apneumatic drill
Rattachments to the vehicle, e.g. rear moun-
ted racks
Rnumber plates (vehicle license plates) that
are not affixed flat against the bumper
Rdirty or icy sensors
Remove adetachable trailer coupling if it is no
longer required. PARKTRONIC measures the
minimum detection range to an obstacle from
the bumper, not the ball coupling.
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