
The multifunction display shows the
Check
Check
trailer hitch lock
trailer hitch lock display message until
the ball coupling is engaged.
X Remove the protective cap from the ball cou-
pling 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 instructions
for 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.
i Fold the ball coupling in if you are not using
the trailer tow hitch.
X Make sure that the vehicle is stationary and
the trailer cables are disconnected.
X Place the protective cap on the ball coupling.
i The release wheel is located behind the left-
hand side trim panel in the luggage compart- ment.
X To open the cover: turn handle:anti-
clockwise, then 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 Press the ball coupling until it engages audibly
behind the bumper.
The indicator lamp on the release knob and
the message in the multifunction display go
out. Coupling up a trailer
X Make sure that the transmission is in position
j.
X Apply the electric parking brake.
X Position the trailer on a level surface behind
the vehicle.
X Couple up the trailer.
X Establish the electrical connection between
the vehicle and the trailer.
X Check that the trailer lighting system is work-
ing.
A connected trailer is only detected when the
electrical connection is established correctly
and when the lighting system is working prop- erly. The function of other systems, 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 rebounding of the overrun brake.
! Remove the installed adapter cable before
folding in the ball coupling. Otherwise, dam-
age may occur to the rear bumper and the
adapter cable.
X Make sure that the transmission is in position
P.
X Apply the electric parking brake.
X Secure the trailer against rolling away.
X Remove the trailer cable and decouple the
trailer. Trailer power supply
! You can connect accessories to the perma-
nent power supply up to a maximum of 240 W. Towing a trailer
215Driving and parking Z

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 work-
shop.
X To switch the connected power supply on
or off: turn the key to position 2or 0respec-
tively (Y page 144). Failure check for LEDs
If LED lamps are fitted in the trailer, a malfunc-
tion message may appear in the multifunction
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 indi-
cator, 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 connect
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. Otherwise, dam-
age 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. 216
Towing a trailerDriving and parking

Safety systems
Display messages
Possible causes/consequences and
M
MSolutions !÷
currently unavaila‐
currently unavaila‐
ble ble See
SeeOwner's
Owner's Man‐
Man‐
ual
ual ABS (Anti-lock Braking System), BAS (Brake Assist System), ESP
®
(Electronic Stability Program), ESP ®
trailer stabilisation, the HOLD
function, hill start assist and PRE-SAFE ®
are temporarily unavailable.
Adaptive brake lights and Active Brake Assist may have also failed.
In addition, the !,÷andå warning lamps may light up in
the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes:
R self-diagnosis is not yet complete
R the on-board voltage may be insufficient
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
The steerability and braking characteristics may be severely affected. The braking distance may increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased risk of skidding and/or accident.
X Carefully drive on a suitable stretch of road, making slight steering
movements, at a speed above 20 km/h.
If the display message disappears, the functions mentioned above
are available again.
If the multifunction display still shows the display message: X Drive on carefully.
X Consult a qualified specialist workshop immediately. !÷
inoperative inoperative See
See Own‐
Own‐
er's Manual
er's Manual ABS, BAS, ESP
®
, ESP ®
trailer stabilisation, the HOLD function, hill
start assist and PRE-SAFE ®
are unavailable due to a malfunction.
Adaptive brake lights and Active Brake Assist may have also failed.
The !, ÷,åandJ warning lamps may also light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
The steerability and braking characteristics may be severely affected. The braking distance may increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased risk of skidding and/or accident.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. Display messages
235On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions ÷
currently unavaila‐ currently unavaila‐
ble ble
See
SeeOwner's
Owner's Man‐
Man‐
ual
ual ESP
®
, ESP ®
trailer stabilisation, BAS, the HOLD function, hill start
assist and PRE-SAFE ®
are temporarily unavailable.
Adaptive brake lights and Active Brake Assist may have also failed.
In addition, the ÷andå warning lamps may light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
The self-diagnosis function, for example, may not be complete.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance may thus increase in an emergency braking sit-
uation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased risk of skidding and/or accident.
X Carefully drive on a suitable stretch of road, making gentle steering
movements at speeds of above 20 km/h.
If the display message disappears, the functions mentioned above
are available again.
If the multifunction display still shows the display message:
X Drive on carefully.
X Consult a qualified specialist workshop immediately. ÷
inoperative inoperative
See
SeeOwn‐
Own‐
er's Manual
er's Manual ESP
®
, ESP ®
trailer stabilisation, BAS, the HOLD function, hill start
assist and PRE-SAFE ®
are unavailable due to a malfunction.
Adaptive brake lights and Active Brake Assist may have also failed.
In addition, the ÷andå warning lamps may light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance may thus increase in an emergency braking sit-
uation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased risk of skidding and/or accident.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. 236
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions T
!
÷ inoperative
inoperative See
SeeOwn‐
Own‐
er's Manual
er's Manual EBD (electronic brake force distribution), ABS, BAS, ESP
®
, ESP ®
trailer
stabilisation, the HOLD function, hill start assist and PRE-SAFE ®
are
unavailable due to a malfunction.
Adaptive brake lights and Active Brake Assist may have also failed.
A warning tone sounds.
In addition, the ÷,åand! warning lamps may light up in
the instrument cluster.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore lock
if you brake hard, for example.
The steerability and braking characteristics may be severely affected. The braking distance may increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased risk of skidding and/or accident.
X Drive on carefully.
X Consult a qualified specialist workshop immediately. !
Turn on the igni‐ Turn on the igni‐
tion tion
to
torelease
release the
the
parking brake
parking brake The red
!indicator lamp lights up.
You have attempted to release the electric parking brake while the
ignition was switched off.
X Key: turn the key to position 1in the ignition lock.
X KEYLESS-GO: switch on the ignition. !
Release parking Release parking
brake brake The red
!indicator lamp flashes and a warning tone sounds. A
condition for automatic release of the electric parking brake is not
fulfilled (Y page 168).
You are driving with the electric parking brake applied.
X Release the electric parking brake manually. The red
!indicator lamp flashes and a warning tone sounds.
You are initiating emergency braking using the electric parking brake
(Y page 169). !
Parking brake See Parking brake See
Owner's Manual Owner's Manual The yellow
!warning lamp lights up.
The electric parking brake is malfunctioning.
To apply:
X Switch the ignition off.
X Press the electric parking brake handle for at least ten seconds.
X Vehicles with manual transmission: engage first gear.
X Vehicles with automatic transmission: shift the transmission to
position B.
X Consult a qualified specialist workshop. Display
messages
237On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Further information on the automatic front-passenger front airbag
deactivation system (Y page 49).Lights
i Vehicles with LED light bulbs in the light clusters:
The display message for the corresponding lamp only appears when all the LEDs in the lamp have
failed. Display messages
Possible causes/consequences and
M
MSolutions b
Left cornering Left cornering
light light
orRight cor‐
Right cor‐
nering light
nering light The left or right-hand cornering light is faulty.
X Check whether you are permitted to replace the bulb yourself
(Y page 120).
or
X Consult a qualified specialist workshop. b
Left dipped beam Left dipped beam
or
Right dipped beam
Right dipped beam The left or right-hand dipped-beam headlamp is faulty.
X Check whether you are permitted to replace the bulb yourself
(Y page 120).
or
X Consult a qualified specialist workshop. b
Trailer left tail Trailer left tail
lamp lamp
orTrailer
Trailer
right tail lamp
right tail lamp The left or right-hand trailer tail lamp is faulty.
X Consult the manufacturer's operating instructions. b
Trailer left turn Trailer left turn
signal signal
orTrailer
Trailer
right turn signal
right turn signal The left or right-hand trailer turn signal lamp is faulty.
X
Consult the manufacturer's operating instructions. b
Trailer brake lamp Trailer brake lamp The trailer brake lamp is faulty.
X Consult the manufacturer's operating instructions. b
Rear left indicator Rear left indicator
or Rear right indi‐
Rear right indi‐
cator
cator The rear left-hand or rear right-hand turn signal is faulty.
X Check whether you are permitted to replace the bulb yourself
(Y page 120).
or
X Consult a qualified specialist workshop. b
Front Front
left
leftindicator
indicator
or Front right
Front right
indicator
indicator The front left-hand or front right-hand turn signal is faulty.
X Check whether you are permitted to replace the bulb yourself
(Y page 120).
or
X Consult a qualified specialist workshop. 246
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions b
Left tail lamp Left tail lamp
or
Right tail lamp
Right tail lamp The left or right-hand tail lamp is faulty.
X Consult a qualified specialist workshop. b
Left daytime driv‐ Left daytime driv‐
ing lamp ing lamp
orRight
Right
daytime
daytime driving
drivinglamp
lamp The left or right-hand daytime driving lamp is faulty.
X Check whether you are permitted to replace the bulb yourself
(Y page 120).
or
X Consult a qualified specialist workshop. b
Malfunction Malfunction
See
SeeOwn‐
Own‐
er's Manual
er's Manual The exterior lighting is faulty.
X Consult a qualified specialist workshop. Vehicles with trailer tow hitch: a fuse may have blown.
X Stop the vehicle, paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 166).
X Check the fuses (Y page 331).
X If necessary, replace the blown fuse. Observe the warning notes as
you do so.
If the multifunction display still shows the display message: X Consult a qualified specialist workshop. b
AUTO lights inoper‐ AUTO lights inoper‐
ative ative The light sensor is faulty.
X
Consult a qualified specialist workshop. b
Switch off lights Switch off lights The lights are still switched on when you leave the vehicle. A warning
tone also sounds.
X Turn the light switch to the Ãposition. b
Switch on headlamps Switch on headlamps You are driving without dipped-beam headlamps.
X
Turn the light switch to the Lorà position. Adaptive Main-beam Adaptive Main-beam
Assist currently Assist currently
unavailable unavailable
See
SeeOwn‐
Own‐
er's Manual
er's Manual Adaptive Highbeam Assist is deactivated and temporarily inoperative.
Possible causes:
R the windscreen is dirty in the camera's field of vision
R visibility is impaired due to heavy rain, snow or fog
X Clean the windscreen.
If the system detects that the camera is fully operational again, the Adaptive Main-beam Assist available again
Adaptive Main-beam Assist available again message is dis-
played.
Adaptive Highbeam Assist is operational again. Adaptive Main-beam Adaptive Main-beam
Assist inoperative Assist inoperative Adaptive Highbeam Assist is faulty.
X
Consult a qualified specialist workshop. 248
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Blind Spot Assist
Blind Spot Assist
currently unavaila‐ currently unavaila‐
ble ble
See
SeeOwner's
Owner's Man‐
Man‐
ual
ual Blind Spot Assist is temporarily inoperative.
Possible causes:
R the radar sensor system is temporarily inoperative, e.g. due to elec-
tromagnetic radiation emitted by nearby TV or radio stations or
other sources of electromagnetic radiation
R the radar sensor system is outside the operating temperature range
The yellow 9indicator lamps also light up in the exterior mirrors.
Once the causes listed above no longer apply, the display message
disappears.
Blind Spot Assist is operational again.
If the display message does not disappear:
X Stop the vehicle, paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 166).
X Restart the engine. Blind Spot Assist Blind Spot Assist
not available when not available when
towing a trailer towing a trailer
See Owner's Manual See Owner's Manual
. Blind Spot Assist is deactivated while towing a trailer.
You have established the electrical connection between the trailer and
your vehicle.
X Press aon the steering wheel to confirm the display message. Blind Spot Assist
Blind Spot Assist
inoperative inoperative Blind Spot Assist is malfunctioning.
The yellow
9indicator lamps also light up in the exterior mirrors.
X Consult a qualified specialist workshop. Parking Pilot can‐ Parking Pilot can‐
celled celled The driver's door is open and the driver's seat belt has not been fas-
tened.
X Repeat the parking process with the seat belt fastened and the
driver's door closed. You inadvertently touched the multifunction steering wheel while
steering intervention was active.
X While steering intervention is active, make sure not to touch the
multifunction steering wheel. The vehicle has started to skid and ESP
®
has intervened.
X Use Parking Pilot again later (Y page 196).Parking Pilot inop‐ Parking Pilot inop‐
erative erative You have just carried out a large number of turning or parking manoeu-
vres.
Parking Pilot will become available again after approximately ten
minutes (Y page 196).
X Stop the vehicle, paying attention to road and traffic conditions.
X Switch off and restart the engine.
If the multifunction display still shows the display message:
X Consult a qualified specialist workshop. Display
messages
253On-board computer and displays Z