Problems with PARKTRONIC
ProblemPossible causes/consequences andMSolutions
Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is then
deactivated and the
indicator lamp on the
PARKTRONIC button
lights up.PARKTRONIC has malfunctioned and has switched off.
XIf problems persist, have PARKTRONIC checked at a qualified
specialist workshop.
Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is then
deactivated.The PARKTRONIC sensors are dirty or there is interference.
XClean the PARKTRONIC sensors (Ypage 335).
XSwitch the ignition back on.
The problem may be caused by an external source of radio or
ultrasound waves.
XSee if PARKTRONIC functions in a different location.
Active Parking Assist
General notes
Active Parking Assist is an electronic parking
aid with ultrasound. It measures the road on
both sides of the vehicle. A parking symbol
indicates a suitable parking space. Active
steering intervention and brake application
can assist you during parking and when exit-
ing a parking space. You may also use
PARKTRONIC (
Ypage 199).
Important safety notes
Active Parking Assist is merely an aid. It is not
a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking
and exiting a parking space. Make sure that
no persons, animals or objects are in the
maneuvering range.
When PARKTRONIC is switched off, Active
Parking Assist 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 Active Park- ing Assist parking procedure.
!If unavoidable, you should drive over
obstacles such as curbs slowly and not at a
sharp angle. Otherwise, you may damage
the wheels or tires.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for
parking, for example:
Rwhere parking or stopping is prohibited
Rin front of driveways or entrances and exits
Ron unsuitable surfaces
202Driving systems
Driving and parking
Problems with Night View Assist Plus
ProblemPossible causes/consequences andMSolutions
The picture quality of
Night View Assist Plus
has deteriorated.The windshield is fogged up on the inside.
XFold down camera cover (Ypage 337).
XDefrost the windshield (Ypage 141).
The windshield is iced up.
XDe-ice the windshield (Ypage 141).
The windshield wipers are smearing the windshield.
XReplace the wiper blades (Ypage 131).
The windshield is smeared after the vehicle has been cleaned in a
car wash.
XClean the windshield (Ypage 335).
There is windshield chip damage in the camera's field of vision.
XReplace the windshield.
The pedestrian and ani-
mal recognition is not
available.The infrared camera in the radiator grill is dirty.
XUse a soft cloth and water to clean the infrared camera.
Driving Assistance PLUS package
General notes
The Driving Assistance PLUS package con-
sists of DISTRONIC PLUS (
Ypage 182), Active
Blind Spot Assist (
Ypage 222) and Active
Lane Keeping Assist (
Ypage 225).
Active Blind Spot Assist
General notes
Active Blind Spot Assist uses a radar sensor
system, pointed toward the rear of the vehi-
cle, to monitor the area to the sides of the
vehicle which the driver is unable to see. A
warning display in the exterior mirrors draws
your attention to vehicles detected in the
monitored area. If you then switch on the cor-
responding turn signal to change lanes, you
will also receive a visual and audible collision
warning. If a risk of lateral collision is detec- ted, corrective braking may help you avoid a
collision. Before a course-correcting brake
application, Active Blind Spot Assist evalu-
ates the space in the direction of travel and at
the sides of the vehicle. For this, Active Blind
Spot Assist uses radar sensors which are
pointed in the direction of travel.
Active Blind Spot Assist supports you from a
speed of approximately 20 mph (30 km/h)
.
Important safety notes
Active Blind Spot Assist is only an aid and is
not a substitute for attentive driving.
GWARNING
Active Blind Spot Assist does not react to:
Rvehicles overtaken too closely on the side,
placing them in the blind spot area
Rvehicles which approach with a large speed
differential and overtake your vehicle
222Driving systems
Driving and parking
If a course-correcting brake application
occurs, red warning lamp:flashes in the
exterior mirror and a dual warning tone
sounds. In addition, 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-
correcting brake application may be interrup-
ted at any time if you steer slightly in the
opposite direction or accelerate.
The course-correcting brake application is
available in the speed range between 20 mph (30 km/h) and 120 mph (200 km/h).
Either no braking application, or a course-
correcting brake application adapted to the
driving situation occurs if:
Rthere are vehicles or obstacles, e.g. crash
barriers, located on both sides of your vehi-
cle.
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 246).
XTurn the SmartKey to position 2in the igni-
tion lock.
Warning lamps :in the exterior mirrors
light up red for approximately 1.5 seconds. Gray radar waves propagating backwards
appear next to the vehicle in the assistance
display 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 multi-
function camera :at the top of the wind-
shield. Various different areas to the front,
rear and side of your vehicle are also moni-
tored 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 unintentionally. If
you do not react to the warning, a lane-cor-
recting 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 accident nor override the laws of phys-
ics. Active Lane Keeping Assist cannot take
account of road and weather conditions. It
may not recognize 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.
Active Lane Keeping Assist cannot continu-
ously keep your vehicle in its lane.
GWARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings.
Driving systems225
Driving and parking
Z
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 func-
tion if:
Rthere is poor visibility, e.g. due to insuffi-
cient illumination of the road, or due to
snow, rain, fog or spray
Rthere is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
Rthe windshield is dirty, fogged up, damaged or covered, for instance by a sticker, in the
vicinity of the camera
Rthe radar sensors in the front or rear bump-
ers or the radiator trim are dirty, e.g.
obscured by snow
Rthere are no, several or unclear lane mark- ings for a lane, e.g. in areas with road con-
struction work
Rthe lane markings are worn away, dark or
covered up, e.g. by dirt or snow
Rthe distance to the vehicle in front is too
small and the lane markings thus cannot be
detected
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-correcting 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 steer-
ing wheel for up to 1.5 seconds.
In order that you are warned only when nec-
essary and in good time if you cross the lane
marking, the system recognizes certain con-
ditions 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 high-
way.
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 circum-
stances 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
226Driving systems
Driving and parking
Display messagesPossible causes/consequences andMSolutions
#
Check Brake Pad
Wear
The brak epads/lining shav ereached their wear limit.
US Aonly: th ered $ brakesystem warnin glamp also lights up
while th eengin eis running .
XVisitaqualified specialist workshop .
G
Inoperative
Oneor mor emain features of th embrace system are malfunc -
tioning.
XHav eth embrace system checke dat aqualified specialist work-
shop.
Collision Preven ‐
tionAssist Plu s
Currently Unavail‐
ableSee Opera‐
tor's Manual
COLLISION PREVENTION ASSIST PLU Sis temporarily no topera-
tional. Possibl ecauses are:
Rth erada rsensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radi osta-
tion sor other source sof electromagnetic radiation .
Rthesystem is outside th eoperating temperature range.
Rth eon-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay mes -
sage 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 170).
XRestart th eengine.
Collision Preven ‐
tionAssist Plu s
Inoperative
COLLISION PREVENTION ASSIST PLU Sis temporarily inoperative
due to amalfunction .Adaptive Brake Assis tmay also hav efailed.
XVisit aqualified specialist workshop .
PRE-SAFE Inopera‐
tiveSee Opera‐
tor's Manual
Importan tfunction sof PRE-SAF E®havefailed. Al lother occupant
safet ysystems ,e.g. air bags ,remain available.
XVisit aqualified specialist workshop immediately.
Display messages25 9
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
PRE-SAFEFunctions
Currently Limited
SeeOperator'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 erada rsensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radi osta-
tion sor other source sof electromagnetic radiation .
Rthesystem is outside th eoperating temperature range.
Rth eon-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay mes -
sage 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 170).
XRestart th eengine.
PRE-SAFEFunctions
Limite 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 .
260Display messages
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
Radar Sensors
Dirty See Opera‐
tor's Manual
At leaston eof th efollowing drivin gsystems or drivin gsafet ysys-
tems is temporarily restricted or inoperative:
RPRE-SAF E®PLUS
RPRE-SAF E®Brake
RCOLLISION PREVENTION ASSIST PLU S
RActive LaneKeepin gAssis t
RActive Blind Spot Assis t
RDISTRONIC PLUSwit hSteerin gAssis tand Stop&Go Pilo t
If th erada rsensor system in fron tis dirty, Active Blind Spot Assis t
will no tperform acourse-correcting brak eapplication .
Possibl ecauses are:
Rth esensor sin th eradiato rtrim and/o rin th ebumpers are dirty
Rth efunction of th edrivin gsystem and/o rdrivin gsafet ysystem
is impaire ddue to heav yrain or snow.
A warnin gtone also sounds.
Whe nth ecauses state dabov eno longer apply, th edisplay mes -
sage disappears. Al ldrivin gsystems and drivin gsafet ysystems
are 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 170).
XSwitchof fth eengine.
XClean th esensor sin th efollowing location s (Ypage 335):
Rin theradiato rtrim
Rin th efron tbumper
Rin th erear bumper, particularl yin th emiddle of th erear
bumper
XRestart th eengine.
The display message disappears.
Display messages26 1
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
DISTRONICPLUSNow
Available
DISTRONIC PLU Sis operational again after havin gbeen tempo -
rarily unavailable .You can no wreactivat eDISTRONIC PLU S
(
Ypage 182).
DISTRONICPLU SCur‐
rentlyUnavailable
SeeOperator' sMan‐
ual
DISTRONIC PLU Sis temporarily inoperative.
Steerin gAssis tand Stop&Go Pilo tare temporarily inoperative.
Possibl ecauses are:
Rth erada rsensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radi osta-
tion sor other source sof electromagnetic radiation .
Rthesystem is outside th eoperating temperature range.
Rth eon-boar dvoltag eis to olow.
A warnin gtone also sounds.
Whe nth ecauses state dabov eno longer apply, th edisplay mes -
sage disappears.
DISTRONIC 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 170).
XRestart th eengine.
DISTRONIC PLU S
Inoperative
DISTRONIC PLUSis defective.
The following may hav ealso failed:
RBA SPLU Swit hCross-Traffic Assis t
RPRE-SAFE®Brake
RSteeringAssis tand Stop&Go Pilo t
A warnin gtone also sounds.
XVisit aqualified specialist workshop .
DISTRONICPLUSSus‐
pended
You hav edepressed th eaccelerato rpedal .DISTRONIC PLU Sis no
longer controllin gth espeed of th evehicle.
XRemove your foot from th eaccelerato rpedal .
DISTRONIC PLU S
- - -mph
An activation condition fo rDISTRONIC PLU Sis no tfulfilled .
XCheckth eactivation condition sfo rDISTRONIC PLU S
(
Ypage 182).
Display messages27 7
On-board computer and displays
Z