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/deactivating
XTurn the SmartKey to position 2in the ignition
lock (Ypage 123).
XTo activate: press thegbutton.
The indicator lamp in the gbutton lights
up.
Dual-zone automatic climate control: air-recir-
culation mode is automatically activated at high outside temperatures.
3-zone automatic climate control: air-recircula-
tion mode is automatically activated at high lev-
els of pollution or at high outside temperatures.
When air-recirculation mode is activated auto-
matically, the indicator lamp above the g
button does not light up. Outside air is added
after approximately 30 minutes.
XTo deactivate: press thegbutton.
The indicator lamp in the gbutton goes
out. Air-recirculation mode deactivates automati-
cally:
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
The residual heat function is only available with
3-zone automatic climate control.
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.
Activating/deactivating
XTurn the SmartKey to position 0in the ignition
lock or remove it (Ypage 123).
XTo switch on: press theÌbutton.
The indicator lamp in the Ìbutton lights
up.
If the residual heat function is activated, the
windows may fog up on the inside.
The blower will run at a low speed regardless of
the airflow setting.
If you activate the residual heat function at high
temperatures, only the ventilation will be acti-
vated. The blower runs at medium speed.
120Operating the climate control systems
Climate control
thought out system – for the safety of the vehi-
cle occupants and that of other road users.
Further information on driving safety systems
(
Ypage 64).
Cruise control
General notes
Cruise control maintains a constant road speed
for you. It brakes automatically in order to avoid exceeding the set speed. On long and steep
downhill gradients, especially if the vehicle is
laden, you must shift to a lower gear in time. By
doing so, you will make use of the braking effect
of the engine. This relieves the load on the brake
system and prevents the brakes from overheat-
ing and wearing too quickly.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain a steady
speed for a prolonged period. You can store any
road speed above 20 mph (30 km/h).
Important safety notes
If you fail to adapt your driving style, cruise con-
trol can neither reduce the risk of an accident
nor override the laws of physics. Cruise control
cannot take into account the road, traffic and
weather conditions. Cruise control is only an
aid. You are responsible for maintaining a safe
distance to the vehicle in front, for vehicle
speed, for braking in good time and for staying in
lane.
Do not use cruise control:
Rin road and traffic conditions which do not
allow you to maintain a constant speed, e.g. in
heavy traffic or on winding roads
Ron slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
Rwhen there is poor visibility, e.g. due to fog,
heavy rain or snow
If there is a change of drivers, advise the new
driver of the speed stored.
iThe speed indicated in the speedometer
may differ slightly from the speed stored.
Cruise control lever
:Activates or increases speed
;Activates or reduces speed
=Deactivates cruise control
?Activates at the current speed/last stored
speed
When you activate cruise control, the multifunc-
tion display shows the stored speed for five sec-
onds. The ésymbol also appears in the mul-
tifunction display.
Speedometer with segments: when cruise
control is activated, the segments from the
stored speed to the end of the scale light up.
Activation conditions
To activate cruise control, all of the following
activation conditions must be fulfilled:
Rthe parking brake must be released.
Ryou are driving faster than 20 mph (30 km/h).
RESP®must be active, but not intervening.
Rthe transmission must be in position D.
Storing and maintaining the current
speed
You can accept the current speed if you are
driving faster than 20 mph (30 km/h).
XAccelerate the vehicle to the desired speed.
XBriefly press the cruise control lever up :or
down ;.
XRemove your foot from the accelerator pedal.
Cruise control is activated. The vehicle auto-
matically maintains the stored speed.
iCruise control may be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient
evens out. Cruise control maintains the
148Driving system s
Driving an d parking
DISTRONIC PLUS with Steering Assist and
Stop&Go Pilot aids you in keeping the vehicle in
the center of the driving lane by means of mod-
erate steering interventions in a speed range
from 0 - 125 mph (0 - 200 km/h).
It monitors the area in front of your vehicle by
means of multifunction camera:, at the top of
the windshield.
At speeds of 0 - 37 mph (0 - 60 km/h), Stop&Go Pilot focuses on the vehicle in front, taking into
account lane markings, e.g. when following vehi-
cles in a traffic jam.
At speeds of more than 37 mph (60 km/h)
Steering Assist focuses on detected lane mark-
ings (left and right), and only on the vehicle in
front if lane markings are missing.
If these conditions are not present, Steering
Assist and Stop&Go Pilot cannot provide assis-
tance.
DISTRONIC PLUS must be active in order for the
function to be available.
Important safety notes
If you fail to adapt your driving style, DISTRONIC
PLUS with Steering Assist and Stop&Go Pilot
can neither reduce the risk of an accident nor
override the laws of physics. It cannot take
account of road, weather and traffic conditions.
DISTRONIC PLUS with Steering Assist and
Stop&Go Pilot is only an aid. Yo u a
re 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.
DISTRONIC PLUS with Steering Assist and
Stop&Go Pilot does not detect road and traffic
conditions and does not detect all road users. If
you are following a vehicle which is driving
towards the edge of the road, your vehicle 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. after intentionally 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 steer the 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 Stee ring As
sist 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 150).
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
156Driving system s
Driving an d parking
iThe text shown in the multimedia system
depends on the language setting. The follow-
ing are examples of rear view camera displays
in the multimedia system.
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
Rif the camera lens is dirty or obstructed
Observe the notes on cleaning
(
Ypage 274)
Rif the rear of your vehicle is damaged. In this
event, have the camera position and setting
checked at a qualified specialist workshop
The field of vision and other functions of the rear
view camera may be restricted due to additional
accessories on the rear of the vehicle (e.g.
license plate holder, bicycle rack).
On vehicles with height-adjustable chassis,
leaving the standard height can result in inac-
curacies in the guide lines, depending on tech-
nical conditions.
iThe rear view camera is protected from rain-
drops and dust by means of a flap. When the
rear view camera is activated, this flap opens.
The flap closes again when:
Ryou have finished the maneuvering process
Ryou switch off the engine
Ryou open the trunk
Observe the notes on cleaning (
Ypage 274).
For technical reasons, the flap may remain
open briefly after the rear view camera has
been deactivated.
Switching the rear view camera on/off
XTo switch on: make sure that the Activa‐
tion by R gearfunction is selected in the
multimedia system (see Digital Operator's
Manual).
XEngage reverse gear.
The rear view camera flap opens. The multi-
media system shows the area behind the vehi-
cle with guide lines.
The image from the rear view camera is avail-
able throughout the maneuvering process.
XTo switch off: shift the transmission to posi-
tion P.
or
XDrive forwards a short distance.
Displays in the multimedia system
The rear view camera may show a distorted view
of obstacles, show them incorrectly or not at all.
The rear view camera does not show objects in
the following positions:
Rvery close to the rear bumper
Runder the rear bumper
Rin the area immediately above the tailgate
handle
!Objects not at ground level may appear to
be further away than they actually are, e.g.:
Rthe bumper of a parked vehicle
Rthe drawbar of a trailer
Rthe ball coupling of a trailer tow hitch
Rthe rear section of an HGV
Ra slanted post
Use the guidelines only for orientation.
Approach objects no further than the bottom-
most guideline.
170Driving systems
Driving and parking
Ryellowbrackets wit hthin lines: PARKTRONI C
is active
Ryello wbrackets wit hnormal lines: an objec tis
presen tin close range of th evehicl e
Rred line: an objec tis presen tin th eimmediat e
close range of th evehicl e
Impor tant safety notes
The 360°camera is only an aid and may sho w a
distorted vie wof obstacles, sho wthem incor-
rectl yor no tat all. The 360°camera is no t a
substitut efor attentive driving.
You are always responsibl efor saf emaneuver-
in gand parking. Whe nmaneuverin gor parking,
mak esur ethat there are no persons, animals or
objects in th earea in whic hyou are maneuver-
ing.
You are always responsibl efor safety, and mus t
always pay attention to your surroundings when
parkin gand maneuvering. This applies to th e
area sbehind ,in fron tof and beside th evehicle.
You could otherwise endanger yourself and oth-
ers .
The 360° camera will no tfunction or will func-
tion in alimite dmanner:
Rif th edoors are open
Rif th eexterio rmirror sare folded in
Rif th etrunk lid is open
Rin heav yrain ,snow or fog
Rat night or in ver ydark places
Rif th ecameras are exposed to ver ybright ligh t
Rif thearea is lit by fluorescent bulbs or LE D
lighting (the display may flicker)
Rif there is asudden chang ein temperature,
e.g. when drivin ginto aheated garage in win -
te r
Rif th ecamera lenses are dirty or covered
Rif th evehicl ecomponent sin whic hth ecam -
eras are installed are damaged. In this eve nt,
h
av eth ecamera position and setting checke d
at aqualified specialist workshop
Do no tuse th e360° camera in this case. You
can otherwise injur eother sor caus edamage to
objects or th evehicle.
Guide lines are always shown at roa dlevel.
The field of vision and other function sof th e
camera system may be restricted due to addi-
tional attachments (e.g. license plat eholder,
rear bicycle carrier). On vehicles wit
hheight-adjustable chassis,
dependin gon technical conditions, leavin gth e
standard height can result in :
Rinaccuracies in theguide lines
Rinaccuracies in th edisplay of generated
images (top view)
Activati onconditions
The imag efrom th e360° camera appears if:
Rth emultimedia system is switched on
Rth e360 °Camerafunction is switched on
Switching onthe 360° camera
XPress th eØ buttonin th ecenter console
for longer than tw oseconds.
Dependin gon whether position Dor Ris
engaged, th efollowin gis shown:
Raspli tscree nwit hto pvie wand th eimag e
from th efron tcamera or
Ra spli tscree nwit hto pvie wand th eimag e
from th erear vie wcamera
or
XBriefly press th eØ buttonin th ecenter
console.
The vehicl emen uis displayed.
XSelec t360 °Cameraand press 7to confirm .
Dependin gon whether position Dor Ris
engaged, th efollowin gis shown:
Raspli tscree nwit hto pvie wand th eimag e
from th efron tcamera or
Ra spli tscree nwit hto pvie wand th eimag e
from th erear vie wcamera
Activating the 360°camera using
re verse gear
The 360° camera images can be automatically
displayed by engagin grevers egear .
XMakesur ethat th eActivatio nby Rgea rfunction is selected in th emultimedia system
(see Digital Operator' sManual).
XTo sho wthe360° camera image :engage
revers egear .
The multimedia system shows th earea
behind th evehicl ein split-scree nmode. You
see th eto pvie wof th evehicl eand th eimag e
from th erear vie wcamera.
174Driving systems
Driving and parking
Speed limit with unknown restriction
:Maximum permitted speed
;Maximum permitted speed for vehicles for
which the restriction in the additional sign isrelevant
=Additional sign for unknown restriction
A maximum permitted speed of 100 mph
(100 km/h) and a speed limit of 80 km/h
(80 mph) apply with an unknown restriction.
Lane Tracking package
General notes
The Lane Tracking package consists of Blind
Spot Assist (Ypage 179) and Lane Keeping
Assist (Ypage 181).
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 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 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
GWARNING
Blind Spot Assist does not react to:
Rvehicles overtaken too closely on the side,
placing them in the blind spot area
Rvehicles 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.
iUSA 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 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.
Monitoring area
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.
Driving systems179
Driving and parking
Z
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
your 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
Rthe road is narrow and winding
Rthere are strong shadows cast on the road
If no vehicle is detected in the adjacent lane and
broken lane markings are detected, no lane-cor-
recting brake application is made.
Warning vibration in the steering wheel
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.
Lane-correcting brake application
GWARNING
A lane-correcting brake application cannot
always bring the vehicle back into the original lane. There is a risk of an accident.
Always steer, brake or accelerate yourself,
especially if Active Lane Keeping Assist warns
you or makes a lane-correcting brake appli-
cation.
GWARNING
Active Lane Keeping Assist only detects traf-
fic conditions or road users to a limited
extent. In very rare cases, the system may
make an inappropriate brake application, e.g. after intentionally driving over a solid lane
marking. There is a risk of an accident.
An inappropriate brake application may be
interrupted at any time if you steer slightly in
the opposite direction. Always make sure that
Driving systems185
Driving and parking
Z
Lights
Display messagesPossible causes/consequences andMSolutions
b
Check Left Low Beam
The bulb in question is malfunctioning.
XVisit a qualified specialist workshop.
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 malfunctioning.
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.
212Display messages
On-board computer and displays