
Problems with PARKTRONIC
ProblemPossible causes/consequences andMSolutions
Only the red segments in
the PARKTRONIC warn-
ing displays are lit. You
also hear a warning tone
for approximately two
seconds.
PARKTRONIC is then
deactivated and the indi-
cator lamp on the
PARKTRONIC button
lights up.PARKTRONIC has malfunctioned and has switched off.
XIf problems persist, have PARKTRONIC checked at a qualified spe-
cialist workshop.
Only the red segments in
the PARKTRONIC warn-
ing displays are lit.
PARKTRONIC is then
deactivated.The PARKTRONIC sensors are dirty or there is interference.
XClean the PARKTRONIC sensors (Ypage 315).
XSwitch the ignition back on.
The problem may be caused by an external source of radio or ultra-
sound 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 inter-
vention and brake application can assist you
during parking and when exiting a parking
space. You may also use PARKTRONIC
(
Ypage 175).
Important safety notes
Active Parking Assist is merely an aid. It is not a
replacement for your attention to your immedi-
ate surroundings. You are always responsible
for safe maneuvering, parking and exiting a
parking space. Make sure that no persons, ani-
mals or objects are in the maneuvering range.
When PARKTRONIC is switched off, Active Park-
ing Assist is also unavailable.
For vehicles with a trailer tow hitch installed, the
minimum length for parking spaces is slightly
longer.
If you have attached a trailer to your vehicle, you
should not use Active Parking Assist. Once the
electrical connection is established between your vehicle and the trailer, Active Parking
Assist is no longer available. PARKTRONIC is
deactivated for the rear area.
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 obsta-
cles 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 park-
ing, for example:
Rwhere parking or stopping is prohibited
Rin front of driveways or entrances and exits
Ron unsuitable surfaces
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Surroundingsmessage appears on the mul-
tifunction display.
iYou will achieve the best results by waiting
for the steering procedure to complete before
pulling away.
If you back up after activation, the steering
wheel is moved to the straight-ahead posi-
tion.
XDrive forward and back up as prompted by the
PARKTRONIC warning displays, several times
if necessary.
Once you have exited the parking space com-
pletely, the steering wheel is moved to the
straight-ahead position. You hear a tone and the Park
AssistSwitchedOffmessage appears
on the multifunction display. You will then have
to steer and merge into traffic on your own.
PARKTRONIC is still available. You can take over
the steering before the vehicle has exited the
parking space completely. This is useful if you
recognize that it is already possible to pull out of
the parking space.
Canceling Active Parking Assist
XStop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at once.
The Park Assist Canceled
message
appears in the multifunction display.
or
XPress the PARKTRONIC button (Ypage 177).
PARKTRONIC is switched off and Active Park-
ing Assist is immediately canceled. The Park
Assist Canceledmessage appears in the
multifunction display.
Active Parking Assist is canceled automatically
if:
Rthe electric parking brake is engaged
Rtransmission position jis selected
Rparking using Active Parking Assist is no lon-
ger possible
Ryou are driving faster than 6 mph (10 km/h)
Ra wheel spins, ESP®intervenes or fails. In
such cases the ÷warning lamp lights up in
the instrument cluster
A warning tone sounds. The parking symbol dis-
appears and the multifunction display shows the
Park Assist Canceled
message.
When Active Parking Assist is canceled, you
must steer and brake again yourself. If a system malfunction occurs, the vehicle is
braked to a standstill. To drive on, depress the
accelerator again.
Rear view camera
General notes
Rear view camera :is an optical parking and
maneuvering aid. It shows the area behind the
vehicle with guide lines in the multimedia sys-
tem.
The area behind the vehicle is displayed as a
mirror image, as in the rear view mirror.
iThe text shown in the multimedia system
depends on the language setting. The follow-
ing are examples of rear view camera displays
in the multimedia system.
Important safety notes
The rear view camera is only an aid. It is not a
replacement for your attention to your immedi-
ate surroundings. You are always responsible
for safe maneuvering and parking. Make sure
that there are no persons, animals or objects in
the maneuvering area while maneuvering and
parking in parking spaces.
Under the following circumstances, the rear
view camera will not function, or will function in
a limited manner:
Rif the tailgate is open
Rin heavy rain, snow or fog
Rat night or in very dark places
Rif the camera is exposed to very bright light
Rif the area is lit by fluorescent bulbs or LED
lighting (the display may flicker)
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The sign indicating the end of a restriction only
appears with the restriction in the instrument
cluster when:
RThe regulation must be observed with the
restriction, or
RTraffic Sign Assist is unable to determine
whether the restriction applies
If Traffic Sign Assist is unable to determine a
maximum permitted speed from any of the avail-
able sources, no speed limit appears in the
instrument cluster either.
Traffic Sign Assist is not available in all coun-
tries. In this case, display :appears in the
assistance graphic (
Ypage 219).
Important safety notes
Traffic Sign Assist is only an aid and is not always
able to correctly display speed limits. Traffic
signs always have priority over the Traffic Sign
Assist display.
The system may be either functionally impaired
or temporarily unavailable if the information in
the digital street map of the navigation system is
incorrect or out of date.
Instrument cluster display
Displaying the assistance graphic
XCall up the assistance graphic display func-
tion using the on-board computer
(
Ypage 219).
Detected traffic signs appear in the instru-
ment cluster.
Speed limit with unknown restriction
:Maximum permitted speed
;Maximum permitted speed for vehicles for
which the restriction in the additional sign is relevant
=Additional sign for unknown restriction
A maximum permitted speed of 80 mph
(80 km/h) and a speed limit of 60 mph
(60 km/h) with an unknown restriction apply.
The unit for the speed limit (km/h or mph)
depends on the country in which you are driving. It is generally neither shown on the traffic sign
nor on the instrument cluster but must be taken
into account when observing the maximum per-
mitted speed.
Lane Tracking package
General notes
The Lane Tracking package consists of Blind
Spot Assist (Ypage 193) and Lane Keeping
Assist (Ypage 195).
Blind Spot Assist
General notes
Blind Spot Assist monitors the areas on either
side of the vehicle that are not visible to the
driver with two lateral, rear-facing radar sen-
sors. A warning lamp lights up in the exterior
mirrors and draws your attention to vehicles
detected in the monitored area. If you then
switch on the corresponding turn signal to
change lane, you will also receive an optical and
audible warning.
Blind Spot Assist supports you from a speed of
approximately 20 mph (30 km/h).
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Driving and parking
Z 

Warning lamp
:Warning lamp
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp :on the correspond-
ing side lights up red. This warning is always
emitted when a vehicle enters the blind spot
monitoring range from behind or from the side.
When you overtake a vehicle, the warning only
occurs if the difference in speed is less than
7 mph (12 km/h).
If you select the reverse gear, Blind Spot Assist is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
Collision warning
If a vehicle is detected in the monitoring range of
Blind Spot Assist and you switch on the corre-
sponding turn signal, a double warning tone
sounds. The red warning lamp flashes on the
relevant exterior mirror. If the turn signal
remains on, detected vehicles are indicated by
the flashing of the red warning lamp on the exte-
rior mirror. There are no further warning tones.
Switching on Blind Spot Assist
XMake sure that Blind Spot Assist is activated
in the on-board computer (Ypage 221).
XTurn the SmartKey to position 2in the igni-
tion lock.
The red warning lamps on the exterior mirrors
light up until the engine is started.
Display in the assistance graphic
When Blind Spot Assist is activated, gray radar
waves propagating backwards appear next to
the vehicle in the assistance display in the mul-
tifunction display (
Ypage 219). Above a speed
of 20 mph (30 km/h), the color of the radar
waves in the assistance graphic changes to
green :. Blind Spot Assist is then ready for use.
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. In this event, Blind Spot Assist is deac-
tivated. The Blind
SpotAssistNotAvail‐able When Towing a Trailer See Opera‐tor's Manualmessage appears in the multi-
function display.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in front of
your vehicle by means of multifunction cam-
era :which is attached behind the top of the
windshield. Active Lane Keeping Assist detects
lane markings on the road and can warn you
before you leave your lane unintentionally.
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Z 

This function is available in the range between
40 mph and 120 mph (60 km/hand 200 km/h).
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.
Important safety notes
GWARNING
Lane Keeping Assist may not always clearly
recognize lane markings.
In this case, Lane Keeping Assist may:
Rgive an unnecessary warning
Rnot give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and stay in lane, in particular if
warned by Lane Keeping Assist.
GWARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is
a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Keep-
ing Assist.
Lane Keeping Assist can neither reduce the risk of an accident if you fail to adapt your driving
style nor override the laws of physics. Lane
Keeping Assist cannot take into account the
road, traffic and weather conditions. Lane Keep-
ing Assist is merely an aid. You are responsible
for the distance to the vehicle in front, for vehi-
cle speed, for braking in good time and for stay-
ing in your lane.
The Lane Keeping Assist does not keep the vehi-
cle in the lane.
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
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 highly variable shade conditions on the roadway
Activating/deactivating Lane Keeping
Assist
XTo activate: press button ;.
Indicator lamp :lights up. The Lane Keep‐
ingAssistOnmessage appears in the mul-
tifunction display. If all conditions have been
satisfied, there may be a warning.
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
the lines in the assistance graphics display
(
Ypage 219) are shown in green. Lane Keep-
ing Assist is ready for use.
XTo deactivate: press button;.
Indicator lamp :goes out. Lane Keeping
Assist is deactivated. The Lane Keeping
Assist Offmessage appears in the multi-
function display.
Selecting Standard or Adaptive setting
XIn the DriveAssistmenu on the on-board
computer, select the LaneKeepingAssistfunction (Ypage 221).
XSelectStandardorAdaptive.
Standard
196Driving systems
Driving an d parking 

WhenStandardis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Ra driving safety system intervenes, e.g. ABS,
BAS or ESP®.
Adaptive
When Adaptive
is selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Ra driving safety system intervenes, e.g. ABS,
BAS or ESP®.
Ryou accelerate hard, e.g. kickdown.
Ryou brake hard.
Ryou steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
Ryou cut the corner on a sharp bend.
In order 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 detects solid lane markings.
The warning vibration occurs later if:
Rthe road has narrow lanes.
Ryou cut the corner on a bend.
Driving Assistance PLUS package
General notes
The Driving Assistance PLUS package consists
of DISTRONIC PLUS (Ypage 164), Active Blind
Spot Assist (Ypage 197) and Active Lane Keep-
ing Assist (Ypage 200).
Active Blind Spot Assist
General notes
Active Blind Spot Assist uses a radar sensor
system, pointed toward the rear of the vehicle,
to monitor the area to the sides of the vehicle
which the driver is unable to see. A warning lamp lights up in the exterior mirrors and draws your
attention to vehicles detected in the monitored
area. If you then switch on the corresponding
turn signal to change lane, you will also receive
an optical and audible warning. If a risk of lateral
collision is detected, corrective braking may
help you avoid a collision. Before a course-cor-
recting brake application, Active Blind Spot
Assist evaluates the space in the direction of
travel and at the sides of the vehicle. For this,
Active Blind Spot Assist uses the forward-facing
radar sensors.
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
As a result, Active Blind Spot Assist may nei-
ther give warnings nor intervene in such sit-
uations. There is a risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
iUSA only: This device has been approved by
the FCC as a "Vehicular Radar System". The
radar sensor is intended for use in an auto-
motive radar system only. Removal, tamper-
ing, or altering of the device will void any war-
ranties, and is not permitted by the FCC. Do
not tamper with, alter, or use in any non-
approved way.
Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
iCanada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause interference,
and
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
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Driving and parking
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Removal, tampering,or altering of th edevice
will voi dany warranties, and is no tpermitted.
Do no ttamper with, alter, or use in any non-
approve dway.
An yunauthorized modification to this device
could voi dth euser's authority to operate th e
equipment.
Rada rsensors
The Active Blind Spot Assist radar sensor sare
integrate dint oth efron tand rear bumpers and
behind acover in th eradiato rtrim. Mak esur e
that th ebumpers and th ecover in th eradiato r
grill are free of dirt ,ice or slush. The rear sensor s
mus tno tbe covered, for exampl eby cycle racks
or overhanging cargo. Followin g asevere impact
or in th eevent of damag eto th ebumpers ,hav e
th efunction of th eradar sensor schecke dat a
qualified specialist workshop. Active Blind Spot
Assist may otherwise no longer wor kproperly.
Monitoring area
GWARNIN G
Active Blind Spot Assist does no tdetec tall
traffic situation sand road users. There is a
ris kof an accident.
Always mak esur ethat there is sufficien tdis-
tance on th eside for other traffic or obstacles.
At adistanc eof approximately 1. 6ft (0. 5m) ;
from the vehicle, Active Blind Spot Assist mon-
itors the area up to 10 ft (3 m) next to =and
behind :your vehicle, as shown in the picture. The detection of obstacles can be impaired in
the case of:
Rthere is dirt on the sensors or anything else
covering the sensors
Rpoor visibility, e.g. due to rain, snow or spray
Vehicles in the monitoring range are then not
indicated.
Active Blind Spot Assist may not detect narrow
vehicles, such as motorcycles or bicycles, or
may only detect them too late.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may be
indicated, especially if the vehicles are not driv-
ing in the middle of their lane. This may be the
case if there are vehicles at the inner edge of
your lane.
Due to the nature of the system:
Rwarnings may be issued in error when driving
close to crash barriers or similar solid lane
borders.
Rwarnings may be interrupted when you are
driving alongside particularly long vehicles,
such as trucks, for a prolonged time.
Warning lamp
:Warning lamp
Active Blind Spot Assist is not operational at
speeds below approximately 20 mph (30 km/h).
Vehicles in the monitoring range are then not
indicated.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp :on the correspond-
ing side lights up red. This warning is always
emitted when a vehicle enters the blind spot
monitoring range from behind or from the side.
When you overtake a vehicle, the warning only
occurs if the difference in speed is less than
7 mph (12 km/h).
198Driving systems
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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.
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 detected 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 recog-
nized.
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. Oncoming vehicles, over-
taking vehicles and vehicles in adjacent lanes
can be detected.
A further lane-correcting brake application can
only occur after your vehicle has returned to the
original lane.
No lane-correcting brake application occurs if:
Ryou clearly and actively steer, brake or accel-
erate.
Ryou cut the corner on a sharp bend.
Ryou have switched on the turn signal.
Ra driving safety system intervenes, e.g. ESP®,
PRE-SAFE®Brake or Active Blind Spot Assist.
Ryou have adopted a sporty driving style with
high cornering speeds or high rates of accel-
eration.
RESP®is switched off.
Rthe transmission is not in position h.
Ron vehicles with a trailer tow hitch, the elec-
trical connection to the trailer has been cor-
rect
ly established.
Ra loss of tire pressure or a defective tire has
been detected and displayed.
Ran obstacle has been detected in the lane in
which you are driving.
Active Lane Keeping Assist may not detect other
road users or traffic situations. An inappropriate
brake application may be interrupted at any time
if you:
Rsteer slightly in the opposite direction.
Rswitch on the turn signal.
Ryou brake or accelerate significantly.
A lane-correcting brake application is interrup-
ted automatically if:
Ra driving safety system intervenes, e.g. ESP®,
PRE-SAFE®Brake or Active Blind Spot Assist.
Rlane markings are no longer detected.
Activating/deactivating Active Lane
Keeping Assist
XTo activate: press button ;.
Indicator lamp :lights up. The Lane Keep‐
ing Assist Onmessage appears on the
multifunction display. If all conditions have
been satisfied, a warning or steering inter-
vention may be made.
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
Driving systems201
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