Problems with the rear window defroster
ProblemPossible causes/consequences andMSolutions
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated.The battery has not been sufficiently charged.
XSwitch off any consumers that are not required, e.g. reading lamps,
interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window defroster
can be activated again.
Switching air-recirculation mode
on/off
General notes
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle from
outside. The air already inside the vehicle will
then be recirculated.
If you switch on air-recirculation mode, the win-
dows can fog up more quickly, in particular at
low temperatures. Only use air-recirculation
mode briefly to prevent the windows from fog-
ging up.
Activating or deactivating
XTurn the SmartKey to position 2in the ignition
lock (Ypage 128).
XTo activate: press thegbutton.
The indicator lamp above the gbutton
lights up.
XTo deactivate: press thegbutton.
The indicator lamp above the gbutton
goes out.
iAir-recirculation mode deactivates auto-
matically:
Rafter approximately five minutes at outside
temperatures below approximately 41 ‡
(5 †)
Rafter approximately five minutes if cooling
with air dehumidification is deactivated
Rafter approximately 30 minutes at outside
temperatures above approximately 41 ‡
(5 †) if the "Cooling with air dehumidifica-
tion" function is activated
Switching the residual heat on or off
General notes
It is possible to make use of the residual heat of
the engine to continue heating the vehicle for
approximately 30 minutes after the engine has
been switched off. The heating time depends on
the set interior temperature.
The "residual heat" function only functions opti-
mally with the side windows closed.
The "residual heat" function only functions opti-
mally with the soft top closed.
Activating/deactivating
XTurn the SmartKey to position 0in the ignition
lock or remove it (Ypage 128).
XTo activate: press theÌbutton.
The indicator lamp above the Ìbutton
lights up.
iIf the residual heat function is activated, the
windows may fog up on the inside.
iThe blower will run at a low speed regardless
of the airflow setting.
iIf you activate the residual heat function at
high temperatures, only the ventilation will be
activated. The blower runs at medium speed.
XTo deactivate: press theÌbutton.
The indicator lamp above the Ìbutton
goes out.
Residual heat is deactivated automatically:
Rafter approximately 30 minutes
Rwhen the ignition is switched on
Rif the battery voltage drops
Operating the climate control systems125
Climate control
cle could come into contact with the curb or
other road boundaries. Be particularly aware of
other road users, e.g. cyclists, that are directly
next to your vehicle.
Obstacles such as building site huts on the lane
or projecting out into the lane are not detected.
An inappropriate steering intervention, e.g. afterintentionally driving over a lane marking, can be
corrected at any time if you steer slightly in the
opposite direction.
DISTRONIC PLUS with Steering Assist and
Stop&Go Pilot cannot continuously keep your
vehicle in lane. In some cases, the steering
intervention is not sufficient to bring the vehicle
back to the lane. In such cases, you must steerthe vehicle yourself to ensure that it does not
leave the lane.
The support provided by the system can be
impaired 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
Rno, or several, unclear lane markings are pres-
ent for one lane, e.g. in a construction area
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 strong shadows cast on the road
The system is switched to passive and no longer
assists you by performing steering interventions if:
Ryou actively change lanes
Ryou switch on the turn signal
Rtake your hands off the steering wheel or do
not steer for a prolonged period of time
iAfter you have finished changing lanes,
Steering Assist and Stop&Go Pilot are auto-
matically active again. DISTRONIC PLUS Steering Assist does not pro-
vide assistance:
Ron very sharp corners
Rwhen a loss of tire pressure or a defective tire
has been detected and displayed
Pay attention also to the important safety notes for DISTRONIC PLUS (
Ypage 153).
The steering interventions are carried out with a
limited steering moment. The system requires
the driver to keep his hands on the steering
wheel and to steer himself.
If you do not steer yourself or if you take your
hands off the steering wheel for a prolonged
period of time, the system will first alert you with
a visual warning. A steering wheel symbol
appears in the multifunction display. If you have
still not started to steer and have not taken hold
of the steering wheel after five seconds at the
l
atest, a warning tone also sounds to remind you
to take control of the vehicle. Steering Assist
and Stop&Go Pilot are switched to passive.
DISTRONIC PLUS remains active.
Activating Steering Assist and Stop&Go
Pilot
XActivate the DISTRONIC PLUS with Steering
Assist and Stop&Go Pilot function using the
on-board computer (
Ypage 197).
The DTR+: Steering Assistant Onmes-
sage appears in the multifunction display.
Steering Assist and Stop&Go Pilot are active.
Information in the multifunction display
If Steering Assist and Stop&Go Pilot are activa-
ted but not ready for a steering intervention,
steering wheel symbol :appears in gray. If the
system provides you with support by means of
steering interventions, symbol :is shown in
green.
Driving systems161
Driving and parking
Z
the steering, before the vehicle has exited the
parking space completely. This is useful, for
example when you recognize that it is already
possible to pull out of the parking space.
Canceling Active Parking Assist
You can cancel Active Parking Assist at any
time.
XStop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at once.
ThePark Assist Canceled
message
appears in the multifunction display and you
hear a tone.
or
XPress the PARKTRONIC button on the center
console (Ypage 165).
PARKTRONIC is switched off and Active Park-
ing Assist is immediately canceled. The Park
Assist Canceledmessage appears in the
multifunction display and you hear a tone.
Active Parking Assist is canceled automatically
if:
Rthe transmission is shifted too early
Rtransmission position Pis 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 your
vehicle with guide lines in the multimedia sys-
tem display.
The area behind the vehicle is displayed as a
mirror image, as in the rear view mirror.
iThe text shown in the multimedia system
display depends on the language setting. The
following are examples of rear view camera
messages in the multimedia system display.
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. When maneu-
vering or parking, make sure that there are no
persons, animals or objects in the area in which you are maneuvering.
Under the following circumstances, the rear
view camera will not function, or will function in
a limited manner:
Rif the trunk lid 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)
Rif there is a sudden change in temperature,
e.g. when driving into a heated garage in win- ter
170Driving system s
Driving an d parking
The 360° camera will not function or will func-
tion in a limited manner:
Rif the doors are open
Rif the exterior mirrors are folded in
Rif the trunk lid is open
Rin heavy rain, snow or fog
Rat night or in very dark places
Rif the cameras are exposed to very bright light
Rif the area is lit by fluorescent bulbs or LED
lighting (the display may flicker)
Rif there is a sudden change in temperature,
e.g. when driving into a heated garage in win-ter
Rif the camera lenses are dirty or covered
Rif the vehicle components in which the cam-
eras are installed are damaged. In this event,have the camera position and setting checked
at a qualified specialist workshop
Do not use the 360° camera in this case. You
can otherwise injure others or cause damage to objects or the vehicle.
Guide lines are always shown at road level.
The field of vision and other functions of the
camera system may be restricted due to addi-
tional accessories on the rear of the vehicle (e.g.
license plate holder, bicycle rack).
On vehicles with height-adjustable chassis,
depending on technical conditions, leaving the
standard height can result in:
Rinaccuracies in the guide lines
Rinaccuracies in the display of generated
images (top view)
Activation conditions
The 360° camera image can be displayed if:
Ryour vehicle is equipped with a 360° camera
Rthe SmartKey is in position 2in the ignition
lock
Rthe multimedia system is switched on
Rthe 360° Camerafunction is switched on
Switching on the 360° camera
XPress the Øbutton in the center console
for longer than two seconds.
Depending on whether position Dor Ris
engaged, the following is shown:
Ra split screen with top view and the image
from the front camera or
Ra split screen with top view and the image
from the rear view camera
or
XPress the Øbutton in the center console.
The vehicle menu is displayed.
XSelect 360°Cameraand press 7to confirm.
Depending on whether position Dor Ris
engaged, the following is shown:
Ra split screen with top view and the image
from the front camera or
Ra split screen with top view and the image
from the rear view camera
Activating the 360° camera using
reverse gear
The 360° camera images can be automatically
displayed by engaging reverse gear.
XMake sure that the SmartKey is in position 2
in the ignition lock.
XMake sure that the Activation by R gearfunction is selected in the multimedia system
(see the separate operating instructions).
XTo show the 360° camera image: engage
reverse gear.
The area behind the vehicle is shown in the
multimedia system display in split-screen
mode. You see the top view of the vehicle and
the image from the rear view camera.
Selecting the split-screen and full
screen displays
Switching between split screen views
XTo switch to the line with the vehicle icons:
slide 5the controller.
XTo select one of the vehicle icons: turn 3
the controller.
XTo switch to 180° View:turn 3 the con-
troller to select 180° View
and press7to
confirm.
iThe 180°Viewoption is only available in the
following views:
RTop view with picture from the rear view
camera
RTop view with picture from the front camera
Driving systems175
Driving and parking
Z
Monitoring range of the sensors
In particular, the detection of obstacles can be
impaired if:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is poor visibility, e.g. due to fog, heavy
rain, snow or spray
Rthere are narrow vehicles, e.g. motorcycles or
bicycles
Rthe road has very wide lanes
Rthe road has narrow lanes
Ryou are not driving in the middle of the lane
Rthere are barriers or similar lane borders
Vehicles in the monitoring range are then not
indicated.
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:
Rwarnings may be issued in error when driving
close to crash barriers or similar solid lane
borders.
Rthe warning is canceled when driving for an
extended period next to long vehicles, such as
trucks.
The two radar sensors for Blind Spot Assist are
integrated into the sides of the rear bumper.
Make sure that the bumper is free of dirt, ice or
slush in the vicinity of the sensors. 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 sensors checked at a quali-
fied specialist workshop. Blind Spot Assist may
otherwise not work properly.
Indicator and warning display
:Indicator lamp (yellow)
Warning lamp (red)
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
When Blind Spot Assist is activated, indicator
lamp :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 indicator 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 :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).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Blind Spot Assist
is no longer active.
The brightness of the indicator or warning lamps
is adjusted automatically according to the ambi-
ent light.
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 :flashes. If the turn
signal remains on, detected vehicles are indica-
ted by the flashing of red warning lamp :.
There are no further warning tones.
Driving systems181
Driving and parking
Z
Switching on Blind Spot Assist
XMake sure that Blind Spot Assist
(Ypage 198) is activated in the on-board
computer.
XTurn the SmartKey to position 2in the ignition
lock.
Warning lamps :in the exterior mirrors light
up red for approximately 1.5 seconds and
then turn yellow.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in front of
your vehicle with camera :, which is mounted
at the top of the windshield. Active Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally.
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 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.
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:
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 reflections (e.g. when 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 strong shadows cast on the road
Switching on Lane Keeping Assist
XSwitch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard
or Adaptive(Ypage 198).
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
the lines in the assistance graphics display
182Driving systems
Driving and parking
RESP®is switched off.
Ra loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist
XMake sure that Active Blind Spot Assist
(Ypage 198) is activated in the on-board
computer.
XTurn the SmartKey to position 2in the ignition
lock.
Warning lamps :in the exterior mirrors light
up red for approximately 1.5 seconds and
then turn yellow.
Active Lane Keeping Assist
General notes
Active Lane Keeping Assist monitors the area in
front of your vehicle by means of multifunction
camera :at the top of the windshield. Various
different areas to the front, rear and side of your
vehicle are also monitored with the aid of the
radar sensor system. Active Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally. If you do not react to the warning, a
lane-correcting application of the brakes can
bring the vehicle back into the original lane.
This function is available in the range between
40 mph and 120 mph (60 km/h and 200 km/h).
For Active Lane Keeping Assist to assist you
when driving, the radar sensor system must be
operational
Important safety notes
If you fail to adapt your driving style, Active Lane
Keeping Assist can neither reduce the risk of
accident nor override the laws of physics. Active
Lane Keeping Assist cannot take account of
road and weather conditions. It may not recog- nize traffic situations. Active Lane Keeping
Assist is only an aid. You are responsible for the
distance to the vehicle in front, for vehicle
speed, for braking in good time and for staying in
you
r lane.
Active Lane Keeping Assist cannot continuously
keep your vehicle in its lane.
GWARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings.
In such cases, Active Lane Keeping Assist
can:
Rgive an unnecessary warning and then
make a course-correcting brake application
to the vehicle
Rnot give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Active Lane Keeping Assist alerts you. Ter-
minate the intervention in a non-critical driv-
ing situation.
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 reflections (e.g. when 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
Rthe radar sensors in the front or rear bumpers
or the radiator trim are dirty, e.g. obscured by
snow
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
186Driving system s
Driving an d parking
Lights
Display messagesPossible causes/consequences andMSolutions
b
CheckLeftLowBeam(example)
The corresponding bulb is faulty.
XVisit a qualified specialist workshop.
or
XCheck whether you are permitted to replace the bulb yourself
(Ypage 113).
iLED light sources: the display message for the corresponding
lamp only appears when all the LEDs in the lamp have failed.
b
Active HeadlampsInoperative
The active light function is faulty.
XVisit a qualified specialist workshop.
b
Malfunction SeeOperator's Manual
The exterior lighting is defective.
XVisit a qualified specialist workshop.
b
Auto Lamp FunctionInoperative
The light sensor is defective.
XVisit a qualified specialist workshop.
b
Switch Off Lights
You leave the vehicle and the lights are switched on. A warning tone
also sounds.
XTurn the light switch to position Ã.
Adaptive HighbeamAssist CurrentlyUnavailable SeeOperator's Manual
Adaptive Highbeam Assist is deactivated and temporarily inoperative.
Possible causes are:
Rthe windshield in the camera's field of vision is dirty.
Rvisibility is impaired due to heavy rain, snow or fog.
XClean the windshield.
If the system detects that the camera is fully operational again, the
Adaptive
HighbeamAssistNowAvailablemessage is displayed.
Adaptive Highbeam Assist is operational again.
Adaptive HighbeamAssist InoperativeAdaptive Highbeam Assist is faulty.
XVisit a qualified specialist workshop.
Display messages211
On-board computer and displays
Z