2018 MERCEDES-BENZ GLS SUV brake sensor

Problems with Parking Assist PARKTRONIC
ProblemPossible causes/consequences andMSolutions
Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. You also
hear a warning tone for
approximately two sec-
onds.
Parking Assist
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp in
the Parking Assist
PARKTRONIC button
lights up.Parking Assist PARKTRONIC has malfunctioned and has been deacti-
vated.
XIf problems persist, have Parking Assist PARKTRONIC checked at a
qualified specialist workshop.
Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. Parking
Assist PARKTRONIC is
deactivated after
approximately five sec-
onds.The Parking Assist PARKTRONIC sensors are dirty or there is inter-
ference.
XClean the Parking Assist PARKTRONIC sensors (Ypage 334).
XSwitch the ignition back on.
The problem may be caused by an external source of radio or ultra-
sound waves.
XCheck to see if Parking Assist PARKTRONIC works at a different
location.
Parking Pilot
General notes
Parking Pilot is an electronic parking aid with
ultrasound. It measures the road on both sides
of the vehicle. A parking symbol indicates a suit-
able parking space. Active steering intervention
and brake application can assist you during
parking. Parking Assist PARKTRONIC is also
available (
Ypage 192).
Important safety notes
Parking Pilot is only an aid. It is not a replace-
ment for your attention to your immediate sur-
roundings. You are always responsible for safe
maneuvering, parking and exiting a parking
space. Make sure that no persons, animals or
objects are in the path of your vehicle.
When Parking Assist PARKTRONIC is deactiva-
ted, Parking Pilot is also unavailable.
GWARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
result in a collision with another road user.
There is a risk of an accident.
Pay attention to other road users. Stop the
vehicle if necessary or cancel the Parking Pilot
parking procedure.
!If they cannot be avoided, drive over obsta-
cles such as curbs slowly and at an obtuse
angle. Otherwise, you may damage the
wheels or tires.
Parking Pilot may show parking spaces which
are not suitable for parking, e.g.:
Rwhere parking or stopping is prohibited
Rin front of driveways or entrances and exits
Ron unsuitable surfaces
Driving systems195
Driving and parking
Z

DrivingAssistance Plu spackage
General notes
The Driving Assistanc ePlus package consist sof
Distanc ePilo tDISTRONIC (Ypage 176), Active
Blin dSpot Assis t (Ypage 213) and Active Lan e
Keepin gAssis t (Ypage 215).
Active Blind Spot Assist
General notes
Active Blin dSpot Assis tmonitors th eareas on
either sid eof th evehicle that are no tdirectl y
visible to th edriver wit htw olateral, rear-facin g
radar sensors. Awarnin glamp lights up in th e
exterio rmirrors and draws your attention to
vehicles detecte din th emonitored area. If you
then switch on th ecorrespondin gturn signal to
chang elanes, you will also receiv e avisual and
audible collision warning. If aris kof latera lcol-
lision is detected, corrective braking may hel p
you avoid acollision .Before acourse-correcting
brake application ,Active Blin dSpot Assis teval-
uates th espac ein th edirection of trave land at
th esides of th evehicle. Fo rthis, Active Blin d
Spot Assis tuses th eforward-facin gradar sen -
sors.
Active Blin dSpot Assis tsupports you from a
speed of approximately 20 mph (30 km/h).
Important safet ynotes
Active Blin dSpot Assis tis only an aid and is no t
a substitute fo rattentive driving.
GWARNING
Active Blin dSpot Assis tdoe sno treact to :
Rvehicles overtaken to oclosely on th eside,
placin gthem in th eblin dspo tare a
Rvehicles whic happroac hwit h a larg espeed
differential and overtak eyour vehicle
As aresult ,Active Blin dSpot Assis tmay nei-
ther giv ewarnings no rinterven ein suc hsit -
uations. There is aris kof an accident.
Always observ eth etraffic condition scare-
fully, and maintain asaf elatera ldistance.
iUS Aonly: Thi sdevic ehas bee napproved by
th eFCC as a"Vehicular Radar System". The
radar sensor is intended fo ruse in an auto-
motive radar syste monly. Removal, tamper-
ing, or altering of th edevic ewill void any war- ranties, and is no
tpermitte dby th eFCC. Do
no ttampe rwith, alter, or use in any non-
approved way.
An yunauthorized modification to this devic e
could void th euser's authorit yto operat eth e
equipment.
iCanada only: Thi sdevic ecomplies wit h
RSS-210 of Industry Canada. Operation is
subjec tto th efollowin gtw oconditions:
1. Thi sdevic emay no tcause interference,
and
2. Thi sdevic emus taccept any interf erenc
e
re

ceived, includin ginterferenc ethat may
cause undesired operation of th edevice.
Removal, tampering, or altering of th edevic e
will void any warranties ,and is no tpermitted.
Do no ttampe rwith, alter, or use in any non-
approved way.
An yunauthorized modification to this devic e
could void th euser's authorit yto operat eth e
equipment.
Rada rsensor s
The Active Blind Spot Assis tradar sensor sare
integrated into th efron tand rea rbumper sand
behin d acover in th eradiator trim. Mak esur e
that th ebumper sand th ecover in th eradiator
grill are free of dirt, ic eor slush. The sensor s
mus tno tbe covered, fo rexample by cycle racks
or overhangin gloads. Followin gan acciden tor
in th eevent of damage to th ebumpers, hav eth e
function of th eradar sensor schecke dat aquali-
fie dspecialis tworkshop .Active Blin dSpot
Assis tmay otherwise no longer wor kproperly.
Monitoring area
GWARNING
Active Blind Spot Assis tdoe sno tdetec tall
traffic situation sand road users. There is a
ris kof an accident.
Always mak esur ethat there is sufficien tdis -
tanc eon th esid efo rother traffic or obstacles.
Driving systems21 3
Driving an d parking
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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,
red warning lamp :flashes in the exterior mir-
ror and a double warning tone sounds. In addi-
tion, a display underlining the danger of a side
collision 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 (200km/ 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.
Rthe offroad program is activated (vehicles
without the Offroad Engineering package).
Rthe Offroad or Offroad Plus drive program is
activated (vehicles with the Off-Road Engi-
neering package).
Rthe LOW RANGE offroad gear is activated
(vehicles with the Offroad Engineering pack-
age).
Ra loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist
XMake sure that Active Blind Spot Assist
(Ypage 242) is activated in the on-board
computer.
XTurn the SmartKey to position 2in the igni-
tion lock.
Warning lamps :in the exterior mirrors light
up red for approximately 1.5 seconds and
then turn yellow.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection.
This can be accomplished by checking the trailer
lighting. Active Blind Spot Assist is then deacti-
vated. The indicator lamp lights up yellow in the
exterior mirrors and the Active Blind Spot
Asst. Not Available When Towing aTrailer See Operator's Manualmessage
appears in 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
Driving system s215
Driving an d parking
Z

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).
For Active Lane Keeping Assist to assist you
when driving, the radar sensor system must be
operational.
Important safety notes
If you fail to adapt your driving style, Active Lane
Keeping Assist can neither reduce the risk of
accident nor override the laws of physics. Active
Lane Keeping Assist cannot take into account
road, weather or traffic conditions. Active Lane
Keeping Assist is only an aid. You are responsi-
ble for the distance to the vehicle in front, for
vehicle speed, for braking in good 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 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 heavy 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
Rthere are no or several unclear lane markings
for one lane, e.g. roadworks
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 short
and thus the lane markings 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 highly variable shade conditions on the roadway
Rno vehicle is detected in the adjacent lane andthere are broken lane markings
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 order that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, the system detects 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 freeway
Rthe system detects 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
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-
216Driving systems
Driving and parking

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 j.
XVisit aqualified specialist workshop .
$(USAonly)
J(Canada only)
Check Brake Fluid
Level
There is no tenough brak eflui din th ebrak eflui dreservoir .In addition ,
th e$ (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 161).
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 e$ red brak esystem warning lamp is lit while th e
engin eis running.
XVisit aqualified specialist workshop .
G
Inoperative
Oneor mor emain features of th embrace system are malfunctioning .
XVisitaqualified specialist workshop .
ActiveBrakeAssistFunctionsCurrentlyLimitedSee Opera‐tor's Manual
Active Brake Assis twit hcross-traffic function is temporarily inopera-
tive.
Possibl ecauses are:
RThe radar sensor system is temporarily inoperative, e.g. due to
electromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation .
RThe system is outside th eoperating temperature range.
RThe on-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Active Brake Assis twit hcross-traffic function or PRE ‑S AF E
®PLU Sis
functional 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 161).
XRestart th eengine.
254Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
ActiveBrakeAssistFunctionsCurrentlyLimitedSee Opera‐tor's Manual
Active Brake Assis tis unavailable 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.
ActiveBrakeAssistFunctionsCurrentlyLimite dSee Opera‐tor's Manual
Active Brake Assis tor PRE‑ SAFE®PLUSis temporarily inoperative.
Possibl ecauses are:
RFunction is impaire ddue to heav yrain or snow.
RThe radar sensor system is temporarily inoperative, e.g. due to
electromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation .
RMercedes-AMG vehicles: ES P®is deactivated.
RThe system is outside theoperating temperature range.
RThe on-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Active Brake Assis tor PRE‑ SAFE
®PLUSis operative 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 161).
XRestart th eengine.
XMercedes-AMG vehicles: switch ES P®on again(Ypage 71).
ActiveBrakeAssistFunctions Limite dSee Operator'sMan ‐ual
Active Brake Assis twit hcross-traffic function or PRE ‑S AF E®PLU Sis
no tavailable due to amalfunction .
XVisitaqualified specialist workshop immediately.
Display messages25 5
On-board computer and displays
Z

Display messagesPossible causes/consequences andMSolutions
RadarSensorsDirtySee Operator' sMan ‐ual
The radar sensor system is malfunctioning .
Possibl ecauses are:
Rdir ton sensor s
Rheavyrain or snow
Rwhen drivin 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
RActive Brake Assis t
RActive LaneKeepin gAssis t
RActive Blind Spot Assis t
RDistancePilo tDISTRONI C
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 161).
XSwitchoff th eengine.
XClean all sensor s (Ypage 334).
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 44).
6
Front Lef tMalfunc‐tio nServic eRequiredorFrontLef tMalfunctionServic eRequired
The restrain tsystem has malfunctioned at th efron ton th elef tor right .
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.
256Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
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 attemptedto start th eengin ewit hth etransmission in position k
or h.
XShift th etransmission to position jori.
Apply Brake toShift fro m'P'You attempte dto shift th etransmission to position h,kori
without depressing th ebrak epedal .
XDepress th ebrak epedal .
ToDeselectPorN,Depres sBrake andStart Engine
You attempte dto shift th etransmission out of position jori into
another transmission position wit hth eengin eswitched off .
XDepress thebrak epedal .
XStart th eengine.
Apply Brake toSelect RYou haveattempte dto shift from position hto position kwithout
applyin gth ebrakes.
XDepress th ebrak epedal .
XShift th etransmission to position k.
TransmissionNotinPRis kof Vehicl eRollingAwa y
The driver's door is open or no tfully closed and th etransmission is in
position k,iorh.
A warning tone also sounds.
GWARNIN G
The vehicl emay rol laway.
There is aris kof an accident.
XShift th etransmission to position j.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XCloseth edriver's door completely.
Onl yShift to 'P'whe nVehicl eisSta‐tionar y
The vehicl eis moving .
XStop thevehicl esafely as soo nas possible, payin gattention to roa d
and traffic conditions.
XShift th etransmission to position j.
Display messages275
On-board computer and displays
Z