
Active Parking Assist may also display spaces
not suitable for parking, e.g.:
R parking or stopping prohibitions
R in front of driveways or entrances and exits
R unsuitable surfaces
Parking tips:
R on narrow roads, drive as closely as possi-
ble past the parking space
R parking spaces that are littered or over-
grown might be identified or measured
incorrectly
R parking spaces that are partially occupied
by trailer drawbars might not be identified
as such or be measured incorrectly
R snowfall or heavy rain may lead to a parking
space being measured inaccurately
R pay attention to the PARKTRONIC
(Y page 210 )warning messages during the
parking procedure
R you can intervene in the steering procedure
to correct it at any time. Active Parking
Assist will then be cancelled
R when transporting a load which protrudes
from your vehicle, you should not use
Active Parking Assist
R never use Active Parking Assist when snow
chains are fitted
R make sure that the tyre pressures are
always correct. This has a direct influence
on the parking characteristics of the vehi-
cle.
Use Active Parking Assist for parking spaces
that are:
R parallel or at right angles to the direction of
travel.
R on straight roads, not bends
R on the same level as the road, e.g. not on
the pavement
For vehicles with the trailer tow hitch folded
out, 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.
Detecting parking spaces Objects located above the height range of
Active Parking Assist will not be detected
when the parking space is measured. These
are not taken into account when the parking
procedure is calculated, e.g. overhanging
loads, tail sections or loading ramps of goods
vehicles. G
WARNING
If there are objects above the detection range:
R Active Park Assist may steer too early
R the vehicle may not stop in front of these
objects
This could cause a collision. There is a risk of
an accident.
If objects are located above the detection
range, stop and deactivate Active Parking
Assist.
For further information on the detection
range (Y page 209).
Active Parking Assist does not assist you
parking in spaces at right angles to the direc-
tion of travel if:
R two parking spaces are located directly
next to one another
R the parking space is directly next to a low
obstacle such as a low kerb
R you forward park
Active Parking Assist does not assist you
parking in spaces that are parallel or at right
angles to the direction of travel if:
R the parking space is on a kerb
R the system reads the parking space as
being blocked, for example by foliage or
grass paving blocks
R the area is too small for the vehicle to
manoeuvre into
R the parking space is bordered by an obsta-
cle, e.g. a tree, a post or a trailer Driving systems
213Driving and parking Z

Under the following circumstances, the
reversing camera will not function, or will
function in a limited manner:
R if the tailgate is open
R in heavy rain, snow or fog
R at night or in very dark places
R if the camera is exposed to very bright light
R if the area is lit by fluorescent bulbs or LED
lighting (the display may flicker)
R if there is a sudden change in temperature,
e.g. when driving into a heated garage in
winter
R if the camera lens is dirty or obstructed.
Observe the notes on cleaning
(Y page 333)
R if the rear of your vehicle is damaged. In this
case, have the camera position and setting
checked at a qualified specialist workshop.
The field of vision and other functions of the
reversing camera may be restricted due to
additional accessories on the rear of the vehi-
cle (e.g. licence plate holder, bicycle rack).
Activating/deactivating the reversing
camera X
To activate: make sure that the key is in
position 2in the ignition lock.
X Make sure that the Activation by R
Activation by R
gear
gear function is selected in Audio 20/ COMAND Online; see the Digital Owner's
Manual.
X Engage reverse gear.
The area behind the vehicle is shown with
guide lines in the Audio 20/COMAND
Online display.
The image from the reversing camera is
available throughout the manoeuvring
process.
X To change the function mode for vehi-
cles with trailer tow hitch: using the
Audio 20/COMAND controller, select sym- bol :for the "Reverse parking" function or
symbol ;for "Coupling up a trailer".
The symbol of the selected function is high- lighted.
To deactivate: the reversing camera deacti-
vates if you shift the transmission to Por after
driving forwards a short distance.
Displays in the Audio 20/COMAND dis-
play The reversing camera may show a distorted
view of obstacles or show them incorrectly or
not at all. Obstacles are not shown by the
reversing camera in the following locations:
R very close to the rear bumper
R under the rear bumper
R in the area immediately above the tailgate
handle
! 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 bot-
tom-most guideline. 218
Driving systemsDriving and parking

Activating Blind Spot Assist
X Make sure that Blind Spot Assist is activa-
ted in the on-board computer
(Y page 249).
X Turn the key to position 2in the ignition
lock.
Warning lamps :in the exterior mirrors
light up red for approximately 1.5 seconds
and then turn yellow.
Towing a trailer
If you couple up a trailer, make sure that you have correctly established the electrical con-
nection. This can be accomplished by check- ing the trailer lighting. Blind Spot Assist is
then deactivated. The indicator lamps in the
exterior mirrors light up yellow and the
Blind
Blind Spot SpotAssist
Assist not
notavailable
available when
when
towing a trailer See Owner's Manual
towing a trailer See Owner's Manual
message appears in the multifunction dis-
play.
i You can deactivate the indicator lamps in
the exterior mirrors.
To do so, you will need to deactivate Blind
Spot Assist if:
R the key is in position 2in the ignition lock
R the engine is not running
R the electrical connection to the trailer
has been established
Lane Keeping Assist General notes
Lane Keeping Assist monitors the area in
front of your vehicle by means of multifunc- tion camera
:attached at the top of the
windscreen. Lane Keeping Assist detects lane markings on the road and can warn you
before you leave your lane unintentionally.
This function is available in a speed range
between 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 through the
steering wheel for up to 1.5 seconds.
Important safety notes G
WARNING
Lane Keeping Assist cannot always clearly
identify lane markings.
In these cases, Lane Keeping Assist may:
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 in 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.
Always steer, apply the brakes or accelerate
the vehicle yourself, especially if Lane Keep-
ing Assist alerts you.
If you fail to adapt your driving style, Lane
Keeping Assist can neither reduce the risk of
an accident nor override the laws of physics. Lane Keeping Assist cannot take into account
road, weather or traffic conditions. Lane
Keeping Assist is only an aid. You are respon- sible for the distance to the vehicle in front,
for vehicle speed, for braking in good time and
for staying in lane.
Lane Keeping Assist does not keep your vehi- cle in its lane. 228
Driving systemsDriving and pa
rking

note that the power output of the engine,
and consequently the vehicle's gradient-
climbing capability, decrease with increas-
ing altitude. Folding out the ball coupling
G
WARNING
If the ball coupling is not correctly engaged,
the trailer can detach. There is a risk of an
accident.
Always engage the ball coupling as described. G
WARNING
If you release the ball coupling or it does not
engage correctly when folding in, it will swing out. Within pivoting range of the ball coupling,
there is an increased risk of an accident and
injury.
Only release the ball coupling if the pivoting
range is unobstructed. Always make sure that the ball coupling engages when folding in.
Before you can tow a trailer with your vehicle, you must fold out the ball coupling.
The release wheel is located behind the left-
hand side panelling in the luggage compart-
ment. X
To open the cover: turn handle:anti-
clockwise, the fold down and remove
cover ;. X
Pull out release wheel =.
X Turn release wheel =anti-clockwise as far
as it will go.
The ball coupling disengages and folds out
behind the rear bumper. Indicator lamp ?
flashes. X
Pull the ball coupling in the direction of the
arrow until it engages in a vertical position.
The indicator lamp on the release wheel
goes out. The power socket folds down
automatically.
The multifunction display shows the
Check
Check trailer trailer hitch
hitchlock
lockdisplay mes-
sage until the ball coupling is engaged.
X Remove the protective covering from the
ball coupling and store it in a safe place.
X Make sure that the ball of the ball coupling
is clean and that it is either greased or dry
(grease free), depending on the instruc-
tions for the trailer. 232
Towing a trailerDriving an
d parking

Coupling up a trailer
X Make sure that the transmission is in posi-
tion P.
X Apply the electric parking brake.
X Position the trailer horizontally behind the
vehicle.
X Couple up the trailer.
X Establish the electric connection between
the vehicle and the trailer.
X Check that the trailer lighting system is
working.
A connected trailer is only recognised when
the electrical connection is established
correctly and when the lighting system is
working properly. The function of other sys-
tems, such as ESP ®
or PARKTRONIC also
depends on this. Uncoupling a trailer
G
WARNING
If you uncouple a trailer with an engaged over- run brake, you could trap your hand between
the vehicle and the trailer drawbar. This poses a risk of injury.
Do not uncouple a trailer with an engaged
overrun brake.
! Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the rebound- ing of the overrun brake.
! Remove the installed adapter cable
before folding in the ball coupling. Other-
wise, damage may occur to the rear
bumper and the adapter cable.
X Make sure that the transmission is in posi-
tion P.
X Apply the electric parking brake.
X Secure the trailer against rolling away.
X Remove the trailer cable and decouple the
trailer. Folding in the ball coupling
G
WARNING
If you release the ball coupling or it does not
engage correctly when folding in, it will swing out. Within pivoting range of the ball coupling,
there is an increased risk of an accident and
injury.
Only release the ball coupling if the pivoting
range is unobstructed. Always make sure that the ball coupling engages when folding in.
Fold the ball coupling back in if you are not
using the trailer tow hitch.
The release wheel is located behind the left-
hand side panelling in the luggage compart-
ment.
X Place the protective covering on the ball
coupling. X
To open the cover: turn handle:anti-
clockwise, then fold down and remove
cover ;. Towing a trailer
233Driving and parking Z

X
Pull out release wheel =.
X Turn release wheel =anti-clockwise as far
as it will go.
The ball coupling disengages and folds out
behind the rear bumper. Indicator lamp ?
flashes. X
Press the ball coupling in the direction of
the arrow until it engages behind the
bumper.
The indicator lamp on the release knob and
the message in the multifunction display go
out. Trailer power supply
! You can connect accessories to the per-
manent power supply up to a maximum of
240 W.
You cannot charge a trailer battery using
the power supply.
When it leaves the factory, your vehicle's
trailer socket is equipped with a permanent
power supply and a power supply that is
switched on via the ignition lock.
The permanent power supply is supplied via
trailer socket pin 9.
The power supply that is switched on via the
ignition lock is supplied via trailer socket pin
10.
The trailer's permanent power supply is
switched off in the event of low vehicle supply
voltage and after six hours at the latest. You can find more information about fitting
the trailer electrics at a qualified specialist
workshop.
X To switch the connected power supply
on or off: turn the key to position 2or 0
respectively (Y page 157). Failure check for LEDs
If LED lamps are fitted in the trailer, a mal-
function message may appear in the multi-
function display even if there is no fault. The
reason for the error message may be that the
current has fallen below the minimum of
50 mA.
To ensure reliable operation of the failure
indicator, each LED chain in the trailer lighting
must be guaranteed a minimum current of
50 mA. Trailer with 7-pin connector
General notes Trailer with 7-pin connector:
you can con-
nect to the 13-pin socket on the ball coupling
using an adapter or, if necessary, an adapter
cable. Both can be obtained at a qualified
specialist workshop.
Fitting the adapter !
Make sure that there is sufficient cable
play so that the cable cannot become
detached when cornering.
! Remove the installed adapter cable
before folding in the ball coupling. Other-
wise, damage may occur to the rear
bumper and the adapter cable. 234
Towing a trailerDriving and parking

X
Open the socket cover.
X Insert the plug connector with lug :into
groove =on the socket.
X Turn bayonet connection ;clockwise to
the stop.
X Let the cover engage.
X If you are using an adapter cable, secure
the cable to the trailer with cable ties. Towing a trailer
235Driving and parking Z

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos- sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 24). Important safety notes
G
WARNING
Operating the integrated information systems and communications equipment in the vehicle
while driving will distract you from traffic con-
ditions. You could then lose control of the
vehicle. There is a risk of an accident.
Only operate these devices if road traffic con-
ditions permit. If you are unsure about the
surrounding conditions, pull over to a safe
location and make entries only while the vehi-
cle is stationary.
You must observe the legal requirements for
the country in which you are currently driving when operating the on-board computer. G
WARNING
If the instrument cluster has failed or mal-
functioned, you may not recognise function
restrictions relevant to safety. The operating
safety of your vehicle may be impaired. There is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
The on-board computer only shows messages
or warnings from certain systems in the mul- tifunction display. You should therefore make
sure your vehicle is operating safely at all
times. If the operating safety of your vehicle is
impaired, park the vehicle safely as soon as
possible. Contact a qualified specialist work-
shop.
For an overview, see the instrument panel
illustration (Y
page 30). Displays and operation
Instrument cluster lighting
The light sensor in the instrument cluster
automatically controls the brightness of the
multifunction display. In daylight, the displays
in the instrument cluster are not illuminated.
The lighting in the instrument cluster, in the
displays and the controls in the vehicle inte-
rior can be adjusted using the brightness con-
trol knob.
The brightness control knob is located on the bottom left of the instrument cluster
(Y page 30).
X Turn the brightness control knob clockwise
or anti-clockwise.
If the light switch is set to the Ã,Tor
L position, the brightness is dependent
upon the brightness of the ambient light. Speedometer with segments
The speedometer is divided into segments
only on vehicles with DISTRONIC PLUS.
The segments in the speedometer indicate
which speed range is available.
R Variable SPEEDTRONIC activated
(Y page 194):
The segments light up from the start of the
scale to the selected limit speed.
R DISTRONIC PLUS activated (Y page 196):
One or two segments in the set speed
range light up.
R DISTRONIC PLUS detects a vehicle in front
moving more slowly than the stored speed: 238
Displays and operationOn-board computer/Displays