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System limitationsTemporary speedrestrictions (e.g.for a certaintime or duetoweather conditions) cannot beproperlydetectedbythe system. The maximumpermissible speed applyingfor avehicle with atrailer is not detectedbythe system. Inthese sit‐uationsyou must adjustyour speedyourself.
&WARNINGRisk of accident duetoActiveSpeed Limit Assistadaptingthevehicle'sspeed
The speed adoptedbyActive Speed LimitAssistmay betoo high or incorrect in someindividual cases, suchas:
RInthewet or infog
RWhentowing a trailer
#Ensurethatthe driven speed complieswith trafficregulations.
#Adjustthe driving speedtosuit currenttraffic andweather conditions.
Function ofroute-based speed adaptation
%Theavailability ofthefollowing function iscountry-dependent.
When Distance AssistDISTRONIC is active,thefunction adjuststhe speed depending ontherouteevents ahead. Depending onthe drive pro‐gram selected,thevehicle negotiatestherouteevent ahead in a fuel-saving, comfortable ordynamic manner. Whentherouteevent has beenpassed,thevehicle accelerates againtothestored speed. The set distancetothevehicle infront,vehicles detected ahead and speedrestric‐tions ahead aretaken into account.
Route-based speed adjustment canbyconfig‐ured inthe multimedia system (→page 208).
Routeevents ahead are:
RBends
RT-intersections, traffic circles andtollsta‐tions
RTurns andexits
%Whenthetollstation isreached,Active Dis‐tance AssistDISTRONIC adoptsthe speed asthestored speed.
Also,the speed isreduced ifthe turn signaltochange lanes is switched on and one ofthefol‐lowing situations is detected:
RTurning off at intersections
RDriving on slowing-down lanes
RDriving on lanes adjacenttoslowing-downlanes
The driver isresponsibleforchoosingtherightspeed and observingotherroad users. Thisapplies in particulartointersections, traffic cir‐cles and traffic lights, asroute-based speedadaptation does not brakethevehicletoastand‐still.
Whenroute guidance is active,thefirst speedadjustment is carried out automatically. Iftheturn signal indicator is switched on,the selectedroute is confirmed and further speed adjustmentis activated.
Speed adjustment is canceled inthefollowingcases:
RIfthe turn signal indicator is switched offbeforetherouteevent.
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RIfthe driver depressesthe accelerator orbrake pedal duringthe process.
System limitationsRoute-based speed adaptation does nottakeright ofwayregulations into account. The driverisresponsiblefor complying withroad trafficregulations and driving at a suitable speed.
In difficult conditions (e.g. unclearroads, narrowlanes,wetroad surfaces, snow or ice) or whendriving witha trailer,the speed adjustment madebythe system may not always be suitable. Inthese situationsthe driver must interveneaccordingly.
&WARNINGRisk of accident in spiteofroute-based speed adjustment
Route-based speed adjustment might mal‐function or betemporarily unavailable inthefollowing situations:
RIf map data is not uptodate oravailable
RIfyou do notfollowthe selectedrouteguidance
RIfthe setroute isre-planned
RInroad construction areas
RWhentowing a trailer
RIn badweather orroad conditions
RIfthe accelerator pedal is depressed
#Adjustthe speedtothe traffic situation.
Settingroute-based speed adjustment
Requirements:RActive Distance AssistDISTRONIC is activa‐ted.
Multimedia system:
,Vehicle.kAssistance.Speed
Adjustment
#Activate sor deactivate Sthe function.
ActiveSteering Assist
Function ofActiveSteering AssistActiveSteering Assist is country-dependent andonlyavailableforvehicles withthe Driving Assis‐tancePackage.
ActiveSteering Assist is operational at speedsupto130mph (210km/h) and helpsyoutostayinthe center ofthe lanebymeans of moderatesteering interventions. It usesthevehicle in frontandthe lane markings as areference dependingonthe driven speed.
Whenthe system is activelysteering,theèsymbol is shown in green inthe multifunctiondisplay.
Steering andtouch detectionThe driver isrequiredtokeeptheir hands onthesteering wheel at all times andtobe abletointervene at any time. The driver mustexpect achange from activetopassive mode or viceversa at any time.
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Ifthe systemreaches a system limitation orthedriver has notsteeredthevehiclefor a consider‐able period of time or hasremovedtheir handsfromthesteering wheel,the system will,depending onthe situation,first alertthe driverwith a visualwarning. Display1appears inthemultifunction display.Ifthe driverstill does notsteerthevehicle, or hasstill nottaken hold ofthesteering wheel, arepeatedwarningtonesounds in additiontothe visualwarning mes‐sagetoremindthe drivertotakecontrol ofthevehicle.
Thewarning message does not appear or disap‐pears if one ofthefollowing conditions are met:
RThe driversteersthevehicle.
RThe driver presses asteering wheel button oroperatesTouch Control.
ActiveSteering Assist is only an aid. The driver isresponsibleforthe distancetothevehicle infront,forvehicle speed,for braking in good timeandforstaying in lane. Beforechanging lanes,the driver must make surethatthe neighboringlane is free (glanceoverthe shoulder).
System limitationsActiveSteering Assist has a limitedsteeringtor‐quefor lateral guidance. In some cases,thesteering intervention is not sufficienttokeepthevehicle inthe lane.
Ifthe detection of lane markings andvehiclesahead is impaired,ActiveSteering Assistswitchestopassive mode. The system providesno support inthis case. Duringthe transitionfromthe activetopassivestatus,theèsym‐bol is shown as enlarged andflashesyellow.Oncethe system is passivetheèsymbol isgrayed out inthe multifunction display.
The system may be impaired or may not functioninthefollowing instances:
RIn snow,rain,fog, heavy spray, ifthere isglare, direct sunlight,greatlyvarying ambientlight,reflections orstrong shadowsontheroadway.
RInsufficientroad illumination.
RThe windshield inthe area ofthe camera isdirty,fogged up, damaged or covered.
RAbsence of lane markings, or several unclearlane markings, or ifthe markingschangerap‐idly.
RThe distancetothevehicle in front istoosmall andthe lane markingsthus cannot bedetected.
RTheroad is narrow and winding.
RObstacles onthe lane or projecting out intothe lane.
The system does not provide assistance inthefollowing conditions:
ROn tight bends, traffic circles and when turn‐ing.
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RWhen activelychanging lane without switch‐ing onthe turn signal.
&WARNINGRisk of accident ifActiveSteering Assist unexpectedlystops func‐tioning
Ifthe system limitations ofActiveSteeringAssist arereachedthere is no guaranteethatthe system willremain active or willkeepthevehicle in lane.
#Alwayskeepyour hands onthesteeringwheel and observethe traffic carefully.
#Alwayssteerthevehicle paying atten‐tiontotraffic conditions.
&WARNINGRisk of accident ifActiveSteering Assist unexpectedly intervenes
A malfunction inthe detection of lane mark‐ings and objects can occur.
This could cause unexpectedsteering inter‐vention.
#Steer accordingtotraffic conditions.
ActivatingActiveSteering Assist
RequirementsRESP®must be activated, but not intervening.
RActive Distance AssistDISTRONIC is activa‐ted.
#If indicator lamp1is off: press button2.
Function ofActive Lane Change Assist
%Theavailability ofthefollowing function iscountry-dependent.
Active Lane Change Assistsupportsthe driverwhenchanging lanesbyapplyingsteeringtorqueifthe driver operates a turn signal.
Assistance whenchanging lanes is provided if allthefollowing conditions are met:
RYou are driving on a freeway orroad withmultiple lanes inthe direction of travel.
RThe neighboring lane is separatedbya bro‐ken lane marking.
RNovehicle is detected inthe adjacent lane.
RThe driven speed is between 50mph(80 km/h) and110mph (180 km/h).
RActive Lane Change Assistis switched on inthe multimedia system.
RActiveSteering Assist is switched on andactive.
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If novehicle is detected inthe adjacent lane anda lanechange is permitted,thesteering wheelsymbol andthe arroware shown in green2.TheLane Change to the Leftmessage appears,forexample. IfActive Lane Change Assisthasbeen activated withthe turn signal indicator buta lanechange is not immediately possible,thesteering wheel symbolremains green andthearrowappearsgray1. Whenthe lanechangesupportstarts,the turn signal indicator is auto‐matically activated.
If a lanechange is not possible,the arrow fadesout after afew seconds and a new lanechangemust be initiated. An immediate lanechange is
only possible on freeway sections without speedlimits.
Ifthe system is impaired,Active Lane ChangeAssistmay be canceled. If it is canceled,theLane Change Canceledmessage appears inthemultifunction display and awarningtone sounds.
&WARNINGRisk of accident fromchang‐ing lanetoan occupied adjacent lane
Lane ChangeAssistcannot alwaysdetectclearlyifthe adjacent lane is free.
The lanechange might be initiated althoughthe adjacent lane is not free.
#Beforechanging lanes, make surethatthe neighboring lane is free andthere isno dangerto otherroad users.
#Monitorthe lanechange.
&WARNINGRisk of accident if LaneChange Assistunexpectedlystops func‐tioning
Ifthe system limitationsfor Lane ChangeAssist havebeenreached,there is no guar‐anteethatthe system willremain active.
Lane Change Assist cannotthen assistyoubyapplyingsteeringtorques.
#Always monitorthe lanechange andkeepyour hands onthesteering wheel.Observethe traffic conditions andsteerand/or brake if necessary.
System limitationsThe system limitations ofActiveSteering AssistapplytoActive Lane Change Assist(→page 208).
The system may also be impaired or may notfunction inthefollowing situations:
RThe sensors intherear bumper are dirty,damaged or covered,for instanceby asticker or ice and snow.
RTheexterior lighting is malfunctioning.
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