Overview of driving systems and drivingsafety systems
Inthis section,you willfind information aboutthefollowing driving systems and driving safetysystems:
R360° Camera (→page 228)
RABS (Anti-lockBrakingSystem)(→page192)
RActive Distance AssistDISTRONIC(→page203)
RAIRBODYCONTROL (→page215)
RActive Brake Assist (→page196)
RActive LaneKeeping Assist (→page246)
RATTENTION ASSIST (→page 237)
RBAS (BrakeAssistSystem) (→page192)
RHillStart Assist (→page214)
REBD (ElectronicBrakeforceDistribution)(→page196)
RESP®(ElectronicStabilityProgram)(→page193)
RActive Speed Limit Assist (→page 206)
RHOLD function (→page214)
RSTEER CONTROL (→page196)
RActiveSteering Assist (→page 208)
RMAGICBODYCONTROL (→page217)
RNightViewAssist (→page240)
RActiveParking Assist (→page 231)
RParking AssistPARKTRONIC (→page 222)
RRear view camera (→page 226)
RCruise control (→page 200)
RBlind Spot Assist andActive Blind Spot Assist(→page243)
RTraffic Sign Assist (→page 239)
Function of ABS (Anti-lock Braking System)
ABSregulatesthe brake pressure in critical driv‐ing situations:
RDuring braking, e.g. at full brake applicationor insufficient tire traction,the wheels areprevented from locking.
RVehiclesteerability while braking is ensured.
If ABS intervenes when braking,you willfeel apulsing inthe brake pedal. The pulsating brakepedal can be an indication of hazardousroadconditions and can serveas aremindertotakeextra care while driving.
System limitationsRABS is active from speeds of approx. 5mph(8 km/h).
RABS may be impaired or may not function if amalfunction has occurred andtheyel‐low %ABSwarning lamp lights up contin‐uously inthe instrument cluster aftertheengine isstarted.
Function ofBAS (Brake Assist System)
&WARNINGRisk of an accident causedbya malfunction inBAS (Brake AssistSys‐tem)
IfBAS is malfunctioning,the braking distancein an emergency braking situation isincreased.
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125mph (200 km/h) when drivingstraightahead or cornering slightly.
RThevehicle isstabilizedbymeans of individ‐ual brake application on one side.
Function of EBD (electronic brakeforce dis‐tribution)
EBD ischaracterizedbythefollowing:
RMonitoring andregulatingthe brake pressureontherear wheels.
RImproved drivingstability when braking,especially on bends.
Function ofSTEER CONTROL
STEER CONTROL helpsyoubytransmitting anoticeablesteeringforcetothesteering wheel inthe directionrequiredforvehiclestabilization.
Thissteeringrecommendation is given particu‐larlyinthefollowing situations:
RBothright wheels or bothleft wheels are onawet or slipperyroad surface whenyoubrake
RThevehiclestartstoskid
System limitations
STEER CONTROL may be impaired or may notfunction inthefollowing situations:
RESP®is deactivated
RESP®is malfunctioning
RThesteering is malfunctioning
If ESP®is malfunctioning,you will be assistedfurtherbythe electric powersteering.
Function ofActive Brake Assist
Active Brake Assistconsists of:
RDistancewarning function
RAutonomous braking function
RSituation-dependent braking assistance
RVehicles with Driving AssistancePack‐age:EvasiveSteering Assist
Active Brake Assistcan helpyoutominimizetherisk of a collision withvehicles or pedestrians ortoreducethe effects of sucha collision.
IfActive Brake Assisthas detected arisk of colli‐sion, awarningtone sounds andthe
cruise control willresume speedregulation backtothestored speed.
Cruise control is operated usingthe correspond‐ingsteering wheel buttons.You canstore anyspeed above15mph (20 km/h) uptothe maxi‐mum speed.
Ifyoufailtoadaptyour drivingstyle, cruise con‐trol can neitherreducetherisk of an accidentnoroverridethe lawsof physics. It cannottakeinto accountroad,weather or traffic conditions.Cruise control is only an aid.You areresponsibleforthe distancetothevehicle in front,forvehi‐cle speed,for braking in good time andforstay‐ing inyour lane.
Displaysonthe multifunction displayThestatus of cruise control andthestoredspeed are shown inthe multifunction display.
1Cruise control is selected
2Speed is saved, cruise control is deactivated
3Speed is saved, cruise control is activated
%The segments betweenthestored speed andthe end ofthe segment display light up inthe speedometer.
System limitationsCruise control may be unabletomaintainthestored speed on uphill gradients. Thestoredspeed isresumed whenthe gradientevens out.
Change into a lowergear in good time on longandsteep downhill gradients.Takeparticularnoteofthis when driving a ladenvehicle. By
doing so,you will make use ofthe engine's brak‐ing effect. Thisrelievesthe load onthe brakesystem and preventsthe brakes fromoverheat‐ing andwearingtooquickly.
Do not use cruise control inthefollowing situa‐tions:
RIn traffic situations whichrequire frequentchanges of speed, e.g. in heavy traffic, onwindingroads.
ROn slipperyroads.Accelerating can causethe drive wheelstolose traction andthevehicle couldthen skid.
RIfyou are driving when visibility is poor.
Operating cruise control
&WARNINGRisk of accident duetostoredspeed
Ifyou call upthestored speed andthis islowerthanyour current speed,thevehicledecelerates.
#Takeinto accountthe traffic situationbefore calling upthestored speed.
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Active Distance Assist DISTRONIC
Function ofActive Distance AssistDISTRONIC
Active Distance AssistDISTRONIC maintainstheset speed on free-flowingroads. Ifvehicles infront are detected,the set distance is main‐tained, if necessary,untilthevehicle comesto ahalt. Thevehicle accelerates or brakes depend‐ing onthe distancetothevehicle in front andthe set speed. The speed (intherange between15mph (20 km/h) and130mph (210km/h))andthe distancetothevehicle in front are setand saved onthesteering wheel.
Otherfeatures ofActive Distance AssistDISTRONIC:
RAdjuststhe drivingstyle depending ontheselected drive program (fuel-saving, comfort‐able or dynamic) (→page175)
RReactstostationaryvehicles detected inurban speedranges (except bicycles andmotorcycles)
RInitiates accelerationtothestored speed ifthe turn signal indicator is switched ontochangetotheovertaking lane.
RTakes one-sidedovertakingrestrictions intoaccount on highways or on multi-laneroadswith separateroadways (country-dependent).
Vehicles withActiveParking Assist:ifthevehicle has been brakedtoastandstill on multi-lane, separateroadwaysbyActive DistanceAssistDISTRONIC, it can automaticallyfollowthevehicle in front driving off again within30 seconds. If a critical situation is detectedwhen driving off, a visual and acousticwarning isgiven indicatingthatthe driver must nowtakecontrol ofthevehicle. Thevehicle is not acceler‐ated any further.
Active Distance AssistDISTRONIC is only an aid.The driver isresponsibleforkeeping a safe dis‐tancetothevehicle in front,forvehicle speedandfor braking in good time.
System limitations
The system may be impaired or may not functioninthefollowing instances:
RIn snow,rain,fog, heavy spray, ifthere isglare, in direct sunlight or in greatlyvaryingambient light.
RThe windshield inthe area ofthe camera isdirty,fogged up, damaged or covered.
RIftheradar sensors are dirty or covered.
RIn parkinggarages or onroads withsteepuphill or downhill gradients.
RIfthere are narrowvehicles in front, such asbicycles or motorcycles.
In addition, on slipperyroads, braking or accel‐erating can cause one or several wheelstolosetraction andthevehicle couldthen skid.
Do not useActive Distance AssistDISTRONIC inthese situations.
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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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