
Problems with Parking Assist PARKTRONIC
Problem
Possible causes/consequences and
0050
0050Solutions 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.
X If 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.
X Clean the Parking Assist PARKTRONIC sensors (Y page 305).
X Switch the ignition back on. The problem may be caused by an external source of radio or ultra-
sound waves.
X Check to see if Parking Assist PARKTRONIC works at 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. Parking Assist PARKTRONIC is
also available (Y page 173).
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 path of your vehicle.
When Parking Assist PARKTRONIC is deactiva-
ted, Active Parking Assist is also unavailable. G
WARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
cause you to collide with other road users or
objects. There is a risk of an accident.
Pay attention to other road users or objects.
Stop the vehicle if necessary or cancel the
Active Parking Assist 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.
Active Parking Assist may also show parking
spaces that are not suitable for parking, e.g.: R where parking or stopping is prohibited
R in front of driveways or entrances and exits
R on unsuitable surfaces 176
Driving systemsDriving and parking

0087
Yellow guide lines for vehicle width including
the exterior mirrors, for current steering
input (dynamic)
0085 Yellow lanes marking the course the tires
will take at the current steering wheel angle (dynamic) 0083
Yellow guide line at a distance of approx-
imately 3 ft (1.0 m) from the rear area
0084 Vehicle center axle (marker assistance)
006B Bumper
006C Red guide line at a distance of approximately
12 in (0.30 m) from the rear area
The guide lines are shown when the transmis-
sion is in position 005E.
The distance specifications only apply to
objects that are at ground level. 0043
Front warning display
0044 Additional measurement operational readi-
ness indicator for Parking Assist
PARKTRONIC
0087 Rear warning display
Vehicles with Parking Assist PARKTRONIC:
when Parking Assist PARKTRONIC is opera-
tional (Y page 173), additional measurement
operational readiness indicator 0044appears in
the multimedia system. If the Parking Assist
PARKTRONIC warning displays are active or
light up, warning displays 0043and 0087are also active or light up correspondingly in the multi-
media system.
"Reverse parking" function Backing up straight into a parking space
without steering input 0043
White guide line without steering input –
vehicle width including the exterior mirrors
(static)
0044 Yellow guide lines for vehicle width including
the exterior mirrors, for current steering
input (dynamic)
0087 Yellow guide line at a distance of approx-
imately 3 ft (1.0 m) from the rear area
0085 Red guide line at a distance of approximately
12 in (0.30 m) from the rear area
X Make sure that the rear view camera is
switched on (Y page 181).
The lane and the guide lines are shown.
X With the help of white guide line 0043, check
whether the vehicle will fit into the parking
space.
X Using white guide line 0043as a guide, carefully
back up until you reach the end position.
Red guide line 0085is then at the end of the
parking space. The vehicle is almost parallel
in the parking space. 182
Driving systemsDriving and parking

!
Objects not at ground level may appear to
be further away than they actually are, e.g.:
R the bumper of a parked vehicle
R the drawbar of a trailer
R the ball coupling of a trailer tow hitch
R the rear section of an HGV
R a slanted post
Use the guidelines only for orientation.
Approach objects no further than the bottom- most guideline.
Top view with picture from the rear view
camera 0043
Yellow guide line at a distance of approx-
imately 13 ft (4.0 m) from the rear of the
vehicle
0044 Symbol for the split screen setting with top
view and rear view camera image
0087 Guide lines for the maximum steering input
0085 Yellow lane marking the course the tires will
take at the current steering wheel angle
(dynamic)
0083 Yellow guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic) 0084
Vehicle center axle (marker assistance)
006B Yellow guide line at a distance of approx-
imately 3 ft (1.0 m) from the rear of the vehi-
cle
006C Bumper
006D Red guide line at a distance of approximately
12 in (0.30 m) from the rear of the vehicle
The guide lines are shown when the transmis-
sion is in position 005E.
The distance specifications only apply to
objects that are at ground level.
Top view with picture from the front cam-
era 0043
Symbol for the split screen setting with top
view and front camera image
0044 Yellow guide line at a distance of approx-
imately 13 ft (4.0 m) from the front of the
vehicle
0087 Yellow guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic)
0085 Yellow lane marking the course the tires will
take at the current steering wheel angle
(dynamic) Driving systems
187Driving and parking Z

Exiting 360° camera display mode
The 360° camera display is stopped:
R when you select transmission position 005D, or
R when you are driving at moderate speeds
The previous display appears in the multimedia
system. You can also switch the display by
selecting the 0039symbol in the display and
pressing the controller to confirm. ATTENTION ASSIST
General notes ATTENTION ASSIST helps you during long,
monotonous journeys, such as on highways. It is
active in the 37 mph (60 km/h) to 125 mph
(200 km/h) range. If ATTENTION ASSIST
detects typical indicators of fatigue or increas-
ing lapses in concentration on the part of the
driver, it suggests taking a break.
Important safety notes ATTENTION ASSIST is only an aid to the driver. It
might not always recognize fatigue or increasing
inattentiveness in time or fail to recognize them at all. The system is not a substitute for a well-
rested and attentive driver.
The functionality of ATTENTION ASSIST is
restricted and warnings may be delayed or not
occur at all:
R if the length of the journey is less than approx-
imately 30 minutes
R if the road condition is poor, e.g. if the surface
is uneven or if there are potholes
R if there is a strong side wind
R if you have adopted a sporty driving style with
high cornering speeds or high rates of accel-
eration
R if you are predominantly driving slower than
37 mph (60 km/ h)or faster than 125 mph
(200 km/h)
R if you are driving with the Active Steering
Assist of Active Distance Assist DISTRONIC
activated
R if the time has been set incorrectly
R in active driving situations, such as when you
change lanes or change your speed The attention level evaluation is deleted and
restarts when the journey is continued, if:
R you switch off the engine
R you take off your seat belt and open the driv-
er's door, e.g. for a change of drivers or to
take a break
Displaying the attention level You can have current status information dis-
played in the assistance menu (Y
page 216) of
the on-board computer.
X Select the Assistance display for ATTENTION
ASSIST using the on-board computer
(Y page 216).
The following information is displayed: R The length of the journey since the last break.
R The attention level determined by ATTENTION
ASSIST, displayed in a bar display in five levelsfrom high to low.
R If ATTENTION ASSIST is unable to calculate
the attention level and cannot output a warn-
ing, the System suspended System suspended message
appears. The bar display then changes the
display, e.g. if you are driving at a speed below 37 mph (60 km/h) or above 125 mph
(200 km/h).
Activating ATTENTION ASSIST X
Activate ATTENTION ASSIST using the on-
board computer (Y page 217).
The system determines the attention level of
the driver depending on the setting selected:
Standard selected: the sensitivity with which
the system determines the attention level is set to normal.
Sensitive selected: the sensitivity is set higher.
The attention level detected by ATTENTION Driving systems
189Driving and parking Z

Speed limit with unknown restriction
0043
Maximum permitted speed
0044 Maximum permitted speed for vehicles for
which the restriction in the additional sign is
relevant
0087 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. Lane Tracking package
General notes The Lane Tracking package consists of Blind
Spot Assist (Y page 191) and Lane Keeping
Assist (Y page 193).
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 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 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). Important safety notes G
WARNING
Blind Spot Assist does not react to:
R vehicles overtaken too closely on the side,
placing them in the blind spot area
R vehicles which approach with a large speed
differential and overtake your vehicle
As a result, Blind Spot Assist may not give
warnings in such situations. There is a risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
Blind Spot Assist is only an aid. It may fail to
detect some vehicles and is no substitute for
attentive driving. Always ensure that there is
sufficient distance to the side for other road
users and obstacles.
i USA only:
This device has been approved by the FCC as a "Vehicular Radar System". The radar sensor
is intended for use in an automotive radar
system only. Removing, tampering with, or
altering the device will void any warranties,
and is not permitted by the FCC. Do not tam-
per 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.
Radar sensors The radar sensors for Blind Spot Assist are inte-
grated into the rear bumper. Make sure that the bumpers are free from dirt, ice or slush. The
sensors must not be covered, for example by
cycle racks or overhanging loads. Following a
severe impact or in the event of damage to the
bumpers, have the function of the radar sensors
checked at a qualified specialist workshop.
Blind Spot Assist may no longer work properly.
Monitoring area
In particular, the detection of obstacles can be
impaired if:
R there is dirt on the sensors or anything else
covering the sensors
R there is poor visibility, e.g. due to fog, heavy
rain, snow or spray Driving systems
191Driving and parking Z

R
there are narrow vehicles, e.g. motorcycles or
bicycles
R the road has very wide lanes
R the road has narrow lanes
R you are not driving in the middle of the lane
R there are barriers or similar lane borders
Vehicles in the monitoring range are then not
indicated. At a distance of around 1.6 ft (0.5
m)0044 from the
vehicle, Blind Spot Assist monitors the area up
to 10 ft (3 m)next to 0087and behind 0043your
vehicle, as shown in the picture.
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 driving at the inner
edge of their lanes.
Due to the nature of the system:
R warnings may be issued in error when driving
close to crash barriers or similar solid lane
borders.
R the warning is canceled when driving for an
extended period next to long vehicles, such as
trucks.
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. 0043
Warning lamp
If Blind Spot Assist is activated, warning lamp 0043
in the exterior mirrors lights up yellow at speeds
of up to 20 mph (30 km/h). At speeds above
20 mph (30 km/h), the warning lamp goes out
and Blind Spot Assist is operational.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp 0043on 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. Red warning lamp 0043flashes. If the turn
signal remains on, detected vehicles are indica-
ted by the flashing of red warning lamp 0043.
There are no further warning tones.
Switching on Blind Spot Assist X Make sure that Blind Spot Assist is activated
in the on-board computer (Y page 217).
X Turn the SmartKey to position 0048in the igni-
tion lock.
Warning lamps 0043in the exterior mirrors light
up red for approximately 1.5 seconds and
then turn yellow. 192
Driving systemsDriving an
d parking

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 warning lamp lights up yellow in the
exterior mirrors and the Blind Spot Assist Blind Spot Assist
Not Available When Towing a Trailer Not Available When Towing a Trailer
See Operator's Manual See Operator's Manual message appears in
the multifunction display.
i You can deactivate the warning lamps in the
exterior mirrors.
To do so, switch off Blind Spot Assist when:
R the SmartKey is in position 0048in the igni-
tion lock
R the engine is not running
Lane Keeping Assist General notes
0043
Lane Keeping Assist camera
Lane Keeping Assist monitors the area in front of
your vehicle with camera 0043, which is mounted
at the top of the windshield. Lane Keeping Assist
detects lane markings on the road and can warn
you before you leave your lane unintentionally.
This function is available in the range between
40 mph and 120 mph (60 km/h and 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 second s.
Im portant safety notes G
WARNING
Lane Keeping Assist cannot always clearly
detect lane markings. In such cases, Lane Keeping Assist can:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Lane Keeping Assist alerts you. G
WARNING
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.
If you fail to adapt your driving style, Lane Keep- ing Assist can neither reduce the risk of an acci-
dent 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:
R there is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,fog or heavy spray
R there is glare, e.g. from oncoming traffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet)
R the windshield is dirty, fogged up, damaged or
covered, for instance by a sticker, in the vicin-
ity of the camera
R there are no or several unclear lane markings
for one lane, e.g. roadworks
R the lane markings are worn away, dark or cov-
ered up, e.g. by dirt or snow
R the distance to the vehicle in front is too short
and thus the lane markings cannot be detec-
ted
R the lane markings change quickly, e.g. lanes
branch off, cross one another or merge Driving systems
193Driving and parking Z

R
the road is narrow and winding
R there are highly variable shade conditions on
the roadway
Switching on Lane Keeping Assist
X Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard
Standard orAdaptive Adaptive (Ypage 217).
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
the lines in the assistance graphic are shown
in green (Y page 216). Lane Keeping Assist is
ready for use.
Standard If Standard
Standard is selected, no warning vibration
occurs if:
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, e.g. ABS,
BAS or ESP ®
.
Adaptive When Adaptive
Adaptive is selected, no warning vibra-
tion occurs if:
R you have switched on the turn signal; in this
event, the warnings are suppressed for a cer-
tain period of time.
R a driving safety system intervenes, e.g. ABS,
BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard.
R you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
R you cut the corner on a sharp bend.
To ensure that you are warned only when nec-
essary and in good time if you cross the lane
markings, the system detects certain conditions
and warns you accordingly.
The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend
R the road has very wide lanes, e.g. a freeway
R the system detects solid lane markings
The warning vibration occurs later if:
R the road has narrow lanes
R you cut the corner on a bend Driving Assistance Plus package
General notes The Driving Assistance Plus Package consists of
Active Distance Assist DISTRONI C(Ypage 157),
Active Blind Spot Assist (Y page 194) and
Active Lane Keeping Assist (Y page 197).
Active Blind Spot Assist General notes
Active Blind Spot Assist monitors the areas on
either side of the vehicle that are not directly
visible to the driver with two lateral, rear-facing radar sensors. 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 lanes, you will also receive a visual and
audible collision warning. If a risk of lateral col-
lision is detected, corrective braking may help
you avoid a collision. Before a course-correcting
brake application, Active Blind Spot Assist eval- uates 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 sen-
sors.
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. G
WARNING
Active Blind Spot Assist does not react to:
R vehicles overtaken too closely on the side,
placing them in the blind spot area
R vehicles 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.
i USA 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- 194
Driving systemsDriving and pa
rking