brake sensor MERCEDES-BENZ S-Class CABRIOLET 2017 A217 Owner's Guide

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 drivingsituation 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 200)
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
Ifyou fail to adapt your driving style, Active Lane
Keeping Assist can neither reduce the risk of an accident nor override the lawsof physics. Active
Lane Keeping Assist cannot take account of
road and weather conditions. Itmay not recog-
nize traff icsituations. Active Lane Keeping
Assist isonly an aid. You are responsible for the
dist ance to the vehicle in front, for vehicle
speed, for braking ingood time and for staying in
your lane.
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 ina non-critical driv-
ing situation.
The system may be impaired or may not function
if:
Rthere ispoor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,
fog or spray
Rthere isglare, 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
184Driving systems
Driving and parking

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 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 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 second s.
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.
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 recognize 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 be 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. The following vehicles can
have an influence on brake application: oncom-
ing traffic, vehicles that are overtaking and vehi-
cles that are driving parallel to your vehicle.
A further lane-correcting brake application can
only occur after your vehicle has returned to the original lane.
Driving systems185
Driving and parking
Z

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 .
$(USA
only)
J( Canada
only)
Check Brake Fluid
Level
There is no tenough brak efluid in th ebrak efluid reservoir .
In addition ,th e$ (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 140).
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 140).
XRestart th eengine.
210Display messages
On-board computer and displays

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 140).
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.
Display messages21 1
On-board computer and displays
Z

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 140).
XSwitchoff th eengine.
XClean all sensor s (Ypage 284).
XRestart theengine.
The display message disappears.
6
SRSMalfunctionSer ‐viceRequired
The restrain tsystem is malfunctioning .The 6 warning lamp also
lights up in th einstrumen tcluster.
GWARNIN G
The air bags or Emergency Tensioning Devices may either be triggered
unintentionally or, in th eevent of an accident, may no tbe triggered .
There is an increased ris kof injury.
XVisit aqualified specialist workshop immediately.
Fo rfurther information about th erestrain tsystem, see (
Ypage 41).
212Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
TrafficSignAssistInoperativeTraffic Sig nAssis tis malfunctioning .
XVisitaqualified specialist workshop .
ë
Off
The HOLD function is deactivated. th evehicl eis skidding.
A warning tone also sounds.
XReactivat eth eHOLD function later (Ypage 158).
DISTRONIC PLUSOffDISTRONI CPLU Shas been deactivated.
If awarning tone also sounds, DISTRONI CPLU Shas deactivated auto -
matically (
Ypage 150).
DISTRONIC PLU SNowAvailableDISTRONI CPLU Sis operational again after having been temporarily
unavailable .You can no wreactivat eDISTRONI CPLU S (Ypage 150).
DISTRONIC PLU SCur ‐rently UnavailableSee Operator' sMan ‐ual
DISTRONI CPLU Sis temporarily inoperative.
Steering Assis tand Stop&Go Pilo tare temporarily inoperative.
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.
A warning tone also sounds.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
DISTRONI CPLU 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 140).
XRestart th eengine.
DISTRONICPLU SInop‐erativ eDISTRONI CPLU Sis malfunctioning
The followin gmay hav ealso failed:
RBA SPLU Swit hCross-Traffic Assis t
RPRE-SAFE®Brake
RSteering Assis tand Stop&Go Pilo t
A warning tone also sounds.
XVisit aqualified specialist workshop .
DISTRONIC PLUSSus ‐pendedYou hav edepressed th eaccelerato rpedal .DISTRONI CPLU Sis no
longer controllin gth espeed of th evehicle.
XRemove your foo tfrom th eaccelerato rpedal .
DISTRONIC PLU S- - -mphAn activation condition for DISTRONI CPLU Sis no tfulfilled .
XCheckth eactivation condition sfor DISTRONI CPLU S (Ypage 150).
224Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
TirePress.Monito rCurrently Unavaila‐ble
Becausethere is interferenc efrom astron gsource of radi owaves, no
signals from th etire pressur esensor sare detected. The tire pressur e
monitor is temporarily malfunctioning .
XDrive on.
The tire pressur emonitor restarts automatically as soo nas th e
problem has been resolved.
TirePress .Sen ‐sor(s) Missin gThere is no signal from th etire pressur esensor of on eor several
wheels. The pressur eof th eaffecte dtire is no tdisplayed in th emul-
tifunction display.
XHav eth efault ytire pressur esensor replace dat aqualified special -
ist workshop .
TirePressure Moni‐tor Inoperative NoWheel Sensor s
The wheels mounte ddo no thav e a suitable tire pressur esensor .The
tire pressur emonitor is deactivated.
XMoun twheels wit hsuitable tire pressur esensors.
The tire pressur emonitor is activated automatically after drivin gfor
a few minutes.
Tir ePress.Monito rInoperativeThe tire pressur emonitor is faulty.
XVisit aqualified specialist workshop .
Vehicle
Display messagesPossible causes/consequences and MSolutions
Shiftto'P'or'N'to Start EngineYou haveattempte dto start th eengin ewit hth etransmission in posi-
tion Ror D.
XShift th etransmission to position Por N.
Apply Brake toShift fro m'P'You hav eattempte dto mov eth etransmission selector lever to posi-
tion D,Ror Nwithout depressing th ebrak epedal .
XDepress th ebrak epedal .
ToDeselectPorN,Depres sBrake andStart Engine
Wit hth eengin eswitched off ,you hav eattempte dto shift th etrans -
mission out of position Por Nint oanother transmission position .
XDepress thebrak epedal .
XStart th eengine.
Display messages22 7
On-board computer and displays
Z