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,
the red warning lamp flashes in the exterior mir-
ror and a dual warning tone sounds. In addition,
a display underlining the danger of a side colli-
sion 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 radarwaves propagating backwards appear next to
the vehicle in the assistance display on the
multifunction display.
Active Lane Keeping Assist
General notes
Active Lane Keeping Assist monitors the area in
front of your vehicle by means of multifunction
camera :at the top of the windshield. Various
different areas to the front, rear and side of your
vehicle are also monitored with the aid of the
radar sensor system. Active Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally. If you do not react to the warning, a
lane-correcting application of the brakes can
bring the vehicle back into the original lane.
This function is available in a speed range
between 40 mph and 120 mph (60 km/h and
200 km/h).
Important safety notes
If you fail to adapt your driving style, Active Lane
Keeping Assist can neither reduce the risk of an accident nor override the laws of physics. Active
Lane Keeping Assist cannot take account of
road and weather conditions. It may not recog-
nize traffic situations. Active Lane Keeping
Assist is only an aid. You are responsible for the
distance to the vehicle in front, for vehicle
speed, for braking in good time and for staying in
your lane.
206Driving systems
Driving and parking
Active Lane Keeping Assist cannot continuously
keep your vehicle in its lane.
GWARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings.
In such cases, Active Lane Keeping Assist
can:
Rgive an unnecessary warning and then
make a course-correcting brake application
to the vehicle
Rnot give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Active Lane Keeping Assist alerts you. Ter-
minate the intervention in a non-critical driv-
ing situation.
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
Rthe radar sensors in the front or rear bumpers
or the radiator trim are dirty, e.g. obscured by
snow
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 ve hicle 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 strong shadows cast on the road
If no vehicle is detected in the adjacent lane and
broken lane markings are detected, no lane-cor-
recting brake application is made.
Warning vibration in the steering wheel
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.
In orde r 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 highway.
Rthe system recognizes solid lane markings.
The warning vibration occurs later if:
Rthe road has narrow lanes.
Ryou cut the corner on a bend.
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.
GWARNING
Active Lane Keeping Assist does not detect
traffic conditions or road users. In very rare
cases, the system may make an inappropriate brake application, e.g. after intentionally driv-
ing over a solid lane marking. There is a risk of
an accident.
An inappropriate brake application may be
interrupted at any time if you steer slightly in
the opposite direction. Always make sure that
there is sufficient distance on the side for
other traffic or obstacles.
Driving systems207
Driving and parking
Z
Important safety notes
GWARNING
If you operate information systems and com-
munication equipmen tintegrate din th evehi-
cle while driving ,you will be distracte dfrom
traffic conditions. You could also lose control
of th evehicle. Ther eis aris kof an accident.
Only operate th eequipmen twhen th etraffic
situation permits. If you are no tsur ethat this
is possible ,park th evehicl epayin gattention
to traffic condition sand operate th eequip-
men twhen th evehicl eis stationary.
You must observ eth elegal requirements for th e
country in whic hyou are currentl ydriving when
operating th eon-board computer.
GWARNIN G
If th einstrumen tcluste rhas faile dor mal-
functioned, you may no trecognize function
restriction sin systems relevan tto safety. The
operating safet yof your vehicl emay be
impaired .Ther eis aris kof an accident.
Drive on carefully. Hav eth evehicl echecke d
at aqualified specialist workshop immedi-
ately.
If th eoperating safet yof your vehicl eis
impaired ,pull ove ras soo nas it is saf eto do so.
Contac t aqualified specialist workshop.
The on-board computer only shows message sor
warning sfrom certain systems in th emultifunc-
tion display. You should therefor emak esur e
your vehicl eis operating safely at all times .
Fo ran overview, see th einstrumen tpanel illus-
tration (
Ypage 35).
Hybrid vehicles: makesur ethat you read th e
separat eOperator's Manual. Otherwise, you
may no trecognize dangers.
Displays and operation
Instrument cluster lighting
The ligh tsensor in th einstrumen tcluste rauto -
matically control sth ebrightness of th emulti-
function display. In daylight, th edisplays in th einstrumen
tcluste rare illuminated. Adimming
function is no tpossible in daylight.
The lighting in th einstrumen tcluster, in th edis-
plays and th econtrol sin th evehicl einterior can
be adjusted usin gth ebrightness control knob.
The brightness control is locate dbetween th e
instrumen tcluste rand th emultimedia system
display (
Ypage 36).
XTurn thebrightness control knob clockwise or
counter-clockwise.
If you tur nth eligh tswitch (
Ypage 124) to th e
T, ÃorL position ,th ebrightness
will depend upon th ebrightness of th eambi -
en tlight.
Speedometer segments
The segments in th espeedometer indicat e
whic hspee drange is available.
RCruis econtrol activated (Ypage 169):
The segments ligh tup from th estore dspee d
to th een dof th escale.
RDISTRONI CPLU Sactivated (Ypage 171):
On eor two segments in th eset spee drange
ligh tup.
RDISTRONI CPLU Sdetects avehicl ein fron t
moving mor eslowly than th estore dspeed:
The segments between th espee dof th evehi-
cle in fron tand th estore dspee dligh tup.
Tachometer
!
Do no tdriv ein th eoverrevving range, as this
could damag eth eengine.
The red ban din th etachometer indicates th e
engine's overrevving range.
The fuel suppl yis interrupted to protect th e
engin ewhen th ered ban dis reached.
Outside temperature display
You should pay special attention to road condi-
tion swhen temperatures are aroun dfreezing
point.
Bea rin min dthat th eoutside temperature dis-
play indicates th etemperature measured and
does no trecord th eroad temperature.
The outside temperature display is in th emulti-
function display (
Ypage 212).
210Displays and operation
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
The yellow!warning lamp lights up and th ered F (USAonly)
or ! (Canada only) indicator lamp flashes .
It is no tpossibl eto apply th eelectric parking brak emanually.
XShift th etransmission to position P.
XVisitaqualified specialist workshop .
$(USA
only)
J( Canada
only)
Check Brake Fluid
Level
There is no tenough brak eflui din th ebrak efluid reservoir .
In addition ,th e$ (USAonly) or J(Canada only) warning lamp
lights up in th einstrumen tcluste rand awarning tone sounds.
GWARNIN G
The braking effec tmay be impaired.
There is aris kof an accident.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XSecur eth evehicl eagainst rollin gaway (Ypage 162).
XConsult aqualified specialist workshop .
XDo notadd brak efluid .This does no tcorrec tth emalfunction .
#
CheckBrakePadWear
The brak epads/linings hav ereached their wear limit.
US Aonly: th ered $ brakesystem warning lamp also lights up while
th eengin eis running.
XVisit aqualified specialist workshop .
G
Inoperative
Oneor mor emain features of th embrace system are malfunctioning .
XVisitaqualified specialist workshop .
Collision Preven‐tionAssist Plu sCurrently Unavaila‐ble See Operator' sManual
COLLISION PREVENTION ASSIST PLU Sis temporarily no toperational.
Possibl ecauses are:
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation
Rth esystem is outside th eoperating temperature range
Rth eon-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
COLLISION PREVENTION ASSIST PLU Sis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 162).
XRestart th eengine.
Display messages23 3
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
Collision Preven‐tionAssist Plu sInoperative
COLLISION PREVENTION ASSIST PLU Sis temporarily inoperative due
to amalfunction .Adaptive Brake Assis tmay also hav efailed.
XVisit aqualified specialist workshop immediately.
PRE-SAFE Inopera‐tiv eSeeOperator' sManual
Importantfunction sof PRE-SAF E®havefailed. Al lother occupant
safet ysystems ,e.g. air bags ,remain available.
XVisit aqualified specialist workshop immediately.
PRE-SAFE FunctionsCurrently Limite dSee Operator'sMan ‐ual
PRE ‑S AF E®PLU Sor PRE‑SAFE®Brake is temporarily inoperative.
Possibl ecauses are:
Rfunction is impaire ddue to heav yrain or snow
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation
Rth esystem is outside th eoperating temperature range
Rth eon-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
PRE ‑S AF E
®PLU Sand PRE ‑S AF E®Brake are operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 162).
XRestart th eengine.
PRE-SAFE FunctionsLimite dSee Opera‐tor's Manual
PRE ‑S AF E®PLU Sor PRE‑SAFE®Brake is unavailable due to amal-
function .BA SPLU Swit hCross-Traffic Assis tmay also hav efailed.
XVisit aqualified specialist workshop immediately.
234Display messages
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
RadarSensorsDirtySee Operator' sMan ‐ual
The radar sensor system is malfunctioning .
Possibl ecauses are:
RDirt on sensor s
RHeavy rain or snow
RWhendrivin gon inter-urban roads without traffic or infrastructure,
e.g. in desert-like area s
At least on edrivin gsystem or drivin gsafet ysystem is malfunctioning
or is temporarily unavailable :
RPRE-SAFE®PLUS
RPRE-SAF E®Brake
RCOLLISION PREVENTION ASSIST PLU S
RActive LaneKeepin gAssis t
RActive Blind Spot Assis t
RDISTRONICPLU Swit hSteering Assis tand Stop&Go Pilo t
If th eradar sensor system in fron tis dirty, Active Blind Spot Assis twill
no tperfor m acourse-correcting brak eapplication .
A warning tone also sounds.
Once th ecaus eof th eproblem is no longer present, th edrivin gand
drive safet ysystems will be available again .The display message dis-
appears.
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 162).
XSwitchoff th eengine.
XClean all sensor s (Ypage 323).
XRestart theengine.
The display message disappears.
Check Lef tRea rBeltSeeOperator' sManualorCheckRightRea rBeltSeeOperator' sManual
The seat belt buckl eextender on th eright or lef tof th erear compart-
men tis no tin th epredefine dposition .The belt strap may be jammed
in th ebelt tongue.
GWARNIN G
If th eseat belt buckl eextender is no tin th epredefine dposition ,th e
seat belt canno tprovid eth eintended level of protection .
There is an increased ris kof injury.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XReleas eth ejamming.
XRepeat th eseat belt fastenin gprocedure .
Display messages235
On-board computer and displays
Z
Lights
Display messagesPossible causes/consequences andMSolutions
b
CheckLeftLowBeam(Example)
The bulb in question is malfunctioning.
XVisit a qualified specialist workshop.
or
XCheck whether you are permitted to replace the bulb yourself
(Ypage 128).
iLED light sources: the display message for the corresponding
lamp only appears when all the LEDs in the lamp have failed.
b
Malfunction SeeOperator’s Manual
The exterior lighting is malfunctioning.
XVisit a qualified specialist workshop.
b
Auto Lamp FunctionInoperative
The light sensor is malfunctioning.
XVisit a qualified specialist workshop.
b
Switch Off Lights
You leave the vehicle and the lights are switched on. A warning tone
also sounds.
XTurn the light switch to position Ã.
b
Switch On Headlamps
You are driving with low-beam headlamps switched off.
XTurn the light switch to positionLorÃ.
Adaptive HighbeamAssist Plus Inoper‐ative
Adaptive Highbeam Assist Plus is faulty.
XVisit a qualified specialist workshop.
Adaptive HighbeamAssist Plus Cur‐rently UnavailableSee Operator's Man‐ual
Adaptive Highbeam Assist Plus is deactivated and temporarily inop-
erative.
Possible causes are:
Rthe windshield in the camera's field of vision is dirty
Rvisibility is impaired due to heavy rain, snow or fog
XClean the windshield.
If the system detects that the camera is fully operational again, the
Adaptive Highbeam Assist Plus Available Again
message is
displayed.
Adaptive Highbeam Assist Plus is available again.
Display messages241
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
ActiveLaneKeepin gAssist InoperativeActive Lan eKeepin gAssis tis malfunctioning .
XVisitaqualified specialist workshop .
Active Blind SpotAssist CurrentlyUnavailable SeeOperator'sManual
Active Blind Spot Assis tis temporarily inoperative.
Possibl ecauses are:
Rth eradar sensor system is outside th eoperating temperature range
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Active Blind Spot Assis tis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 162).
XRestart th eengine.
Active Blind Spo tAssist InoperativeActive Blind Spot Assis tis malfunctioning .
XVisitaqualified specialist workshop .
ParkAssistCanceledThe driver's door is open .
XRepeat theparking gap measuremen tand parking process wit hth e
driver's door closed .
You touched themultifunction steering whee lwhile steering inter-
vention was active .
XWhilesteering intervention is active ,mak esur ethat th emultifunc-
tion steering whee lis no ttouched unintentionally.
The vehicl ehas started to skid and ES P®has intervened.
XUse Active Parking Assistagain later (Ypage 186).
ParkAssist Inoper ‐ativePARKTRONICis malfunctioning or faulty.
XFollow th einstruction sand helpful hints in th e"Problem swit h
PARKTRONIC" section (Ypage 186).
If th emultifunction display still shows th edisplay message :
XVisitaqualified specialist workshop .
Active Parking Assistis unavailable or faulty.
XSwitc hoff th eignition and restar tth eengine.
If Active Parking Assis tcontinues to be unavailable (the jsymbol is
no tshown in th emultifunction display):
XVisit aqualified specialist workshop .
Display messages247
On-board computer and displays
Z