
:
Red guide line at a distance of approx-
imately 0.30 mfrom the rear of the vehicle
; White guide line without turning the steer-
ing wheel
= End of parking space
X Reverse carefully until you have reached
the end position.
Red guide line :is then at the end of park-
ing space =. The vehicle is almost parallel
in the parking space.
"Coupling up a trailer" function :
Vehicle centre point on the yellow guide
line at a distance of approximately 1.0 m
from the rear of the vehicle
; Trailer drawbar
This function is only available on vehicles with
a trailer tow hitch.
X Before coupling up a trailer, set the height
of trailer drawbar ;so that it is slightly
higher than the ball coupling.
X Position the vehicle centrally in front of
trailer drawbar ;. :
Red guide line at a distance of approx-
imately 0.30 m from the ball coupling
; Trailer drawbar locating aid
= Trailer drawbar
? Symbol for the "Coupling up a trailer"
function
A Ball coupling
X Select symbol ?using the controller.
The "Coupling up a trailer" function is selec- ted. The distance specifications now only
apply to objects that are at the same level
as the ball coupling.
X Reverse carefully, making sure that trailer
drawbar locating aid ;points approx-
imately in the direction of trailer drawbar
=.
X Reverse carefully until trailer drawbar =
reaches the red guide line.
The distance between the trailer drawbar
and the red guide line is now approximately 0.30 m.
X Couple up the trailer (Y page 225). Driving systems
215Driving and parking Z 

Wide-angle function
:
Symbol for the wide-angle view function
; Own vehicle
= PARKTRONIC warning displays
You can also use the reversing camera to
select a wide-angle view.
When PARKTRONIC is operational
(Y page 204), a symbol for your own vehicle
appears in the Audio 20/COMAND Online
display. If the PARKTRONIC warning displays
are active, warning displays =light up in the
Audio 20/COMAND Online display in yellow
or red respectively. ATTENTION ASSIST
General notes ATTENTION ASSIST helps you during long,
monotonous journeys such as on motorways
and trunk roads. It is active in the 60 km/h to
200 km/h speed range. If ATTENTION ASSIST
detects typical indicators of fatigue or
increasing lapses in concentration on the part of the driver, it suggests taking a break.
Important safety notes ATTENTION ASSIST is only an aid. It may not
always detect fatigue or lapses in concentra-
tion until too late, or may not detect 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
approximately 30 minutes
R if the road condition is poor, e.g. if the sur-
face 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
acceleration
R if you are predominantly driving at a speed
below 60 km/h or above 200 km/h
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
ATTENTION ASSIST is reset and starts
assessing your tiredness again when you con- tinue your journey if:
R you switch off the engine
R you take off your seat belt and open the
driver's door, e.g. for a change of drivers or
to take a break
Displaying Attention Level with black
and white multifunction display X
Select the status overview using the on-
board computer (Y page 242).
X Press :to display the ATTEN-
TION ASSIST assessment. 216
Driving systemsDriving and parking 

Due to the nature of the system:
R warnings may be issued in error when driv-
ing close to crash barriers or similar solid
lane borders
R warnings may be interrupted when driving
alongside particularly long vehicles, for
example lorries, for a prolonged time
Warning display :
Warning display
Blind Spot Assist is not active at speeds below approximately 30 km/h. Vehicles in the mon-itoring range are then not indicated.
If Blind Spot Assist is activated, indicator
lamp :in the exterior mirrors lights up yel-
low up to a speed of 30 km/h. At speeds
above 30 km/h, the indicator lamp goes out
and Blind Spot Assist is operational.
If a vehicle is detected within the monitoring
range of Blind Spot Assist at speeds above
30 km/h, warning lamp :on the corre-
sponding side lights up red. This warning
always occurs 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 12 km/h.
The yellow indicator lamp goes out if reverse
gear is engaged. Blind Spot Assist is then
deactivated.
The brightness of the indicator/warning
lamps is adjusted automatically according to the ambient light. Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the
corresponding turn signal, a double warning
tone sounds. Red warning lamp :flashes. If
the turn signal remains on, detected vehicles
are indicated by the flashing of red warning
lamp :. There are no further warning tones.
Activating Blind Spot Assist X Make sure that Blind Spot Assist is activa-
ted in the on-board computer
(Y page 245).
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 222
Driving systemsDriving an
d parking 

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. 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. Towing a trailer
227Driving and parking Z 

The trailer battery may not be charged from
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 159). 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. 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
229Driving 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 Ã,Tor
L, the brightness is dependent upon
the brightness of the ambient light. Coolant temperature gauge
G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade.
The coolant temperature gauge is in the
instrument cluster on the right-hand side
(Y page 30). 232
Displays and operationOn-board computer and displays 

Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 120 †.
At high outside temperatures and when driv-
ing uphill, the coolant temperature may rise
to the end of the scale. Rev counter
! Do not drive in the overrevving range.
Doing so will damage the engine.
The red band in the rev counter indicates the
engine's overrevving range.
The engine is limited within a range to protect the engine when the red band is reached. Outside temperature display
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
Bear in mind that the outside temperature
display indicates the measured air tempera-
ture and not the road surface temperature.
The outside temperature display is in the mul- tifunction display (Y page 235).
Changes in the outside temperature are dis-
played after a short delay. 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 191):
The segments light up from the start of the
scale to the selected limit speed.
R DISTRONIC PLUS activated (Y page 193):
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: The segments between the speed of the
vehicle in front and the stored speed light
up. Operating the on-board computer
:
Multifunction display
; Right control panel
= Left control panel
X To activate the on-board computer: turn
the key to position 1in the ignition lock.
You can control the multifunction display and
the settings in the on-board computer using
the buttons on the multifunction steering
wheel. Displays and operation
233On-board computer and displays Z 

Menus and submenus
Menu overview
Press the =or; button on the steer-
ing wheel to call up the menu bar and select a
menu.
Operating the on-board computer
(Y page 233).
Depending on the equipment fitted in the
vehicle, you can call up the following menus:
R Trip Trip menu (Y page 236)
R Navi
Navi menu (navigation instructions)
(Y page 237)
R Audio
Audio menu (Y page 239)
R Tel
Tel menu (telephone) (Y page 240)
R Assist.
Assist. menu (assistance) (Y page 242)
R Serv.
Serv. menu (Y page 245)
R Settings
Settings menu (settings) (Y page 245)
The Audio
Audio, Navi
NaviandTel
Tel menus differ slightly
in vehicles with Audio 20 and in vehicles with COMAND Online. The examples given in this
Owner's Manual apply to vehicles equipped
with COMAND Online. Trip menu
Standard display X
Press and hold the %button on the
steering wheel until the Trip
Trip menu with
trip meter :and total distance
recorder ;is shown. Trip computer "From start" or "From
reset" :
Distance
; Driving time
= Average speed
? Average fuel consumption
X Press the =or; button on the steer-
ing wheel to select the Trip Tripmenu.
X Press the 9or: button to select
From start
From start orFrom reset
From reset.
The values in the From start
From start submenu are
calculated from the start of a journey whilst
the values in the From reset From resetsubmenu are
calculated from the last time the submenu
was reset (Y page 237).
The From start From start trip computer is automati-
cally reset when:
R the ignition has been switched off for more
than four hours.
R 999 hours have been exceeded.
R 9,999 kilometres have been exceeded.
The From reset
From reset trip computer is automati-
cally reset if the value exceeds 9,999 hours or 99,999 kilometres.
ECO display X
Press the =or; button on the steer-
ing wheel to select the Trip
Tripmenu.
X Press the 9or: button to select
ECO DISPLAY
ECO DISPLAY .236
Menus and submenusOn-board computer and displays