Rif there is a strong side wind
Rif you have adopted a sporty driving style with
high cornering speeds or high rates of accel-
eration
Rif you are predominantly driving at a speed
below 37 mph (60 km/h) or above 124 mph
(200 km/h)
Rif you are driving with the Steering Pilot of
Distance Pilot DISTRONIC activated
Rif the time has been set incorrectly
Rin active driving situations, such as when you
change lanes or change your speed
The ATTENTION ASSIST tiredness assessment
is deleted and restarted when continuing the
journey, if:
Ryou switch off the engine
Ryou take off your seat belt and open the driv-
er's door, e.g. for a change of drivers or to
take a break
Displaying the attention level
In the Assistance menu (Ypage 232) of the on-
board computer, you can call up the current sta-
tus information.
XSelect the Assistance display for ATTENTION
ASSIST using the on-board computer
(
Ypage 231).
The following information appears:
RThe length of the journey since the last break.
Rthe attention level determined by ATTENTION ASSIST (Attention Level), displayed in a
bar display in five levels from high to low.
Rif ATTENTION ASSIST is unable to calculate
the attention level and cannot issue a warn-
ing, the System Suspended
message
appears. The bar display then changes the
display, e.g. if you are driving at a speed below 37 mph (60 km/h) or above 124 mph
(200 km/h).
Activating ATTENTION ASSIST
XActivate ATTENTION ASSIST using the on-
board computer (Ypage 233).
The system determines the attention level of
the driver depending on the setting selected:
Selection Standard
: the sensitivity with which
the system determines the attention level is set
to normal.
Selection Sensitive
: the sensitivity is set
higher. The attention level detected by Attention
Assist is adapted accordingly and the driver is
warned earlier.
When ATTENTION ASSIST is deactivated, the
é symbol appears in the multifunction dis-
play in the assistance graphic display.
When ATTENTION ASSIST has been deactivated,
it is automatically reactivated after the engine
has been stopped. The sensitivity selected cor-
responds to the last selection activated (stand-
ard/sensitive).
Warning in the multifunction display
If fatigue or increasing lapses in concentration
are detected, a warning appears in the multi-
function display: ATTENTION ASSIST
Take aBreak!.
In addition to the message shown in the multi-
function display, you will then hear a warning
tone.
XIf necessary, take a break.
XConfirm the message by pressing the a
button on the steering wheel.
On long journeys, take regular breaks in good
time to allow yourself to rest properly. If you do
not take a break and ATTENTION ASSIST con-
tinues to detect increasing lapses in concentra-
tion, you will be warned again after 15 minutes
at the earliest. This will only happen if ATTEN-
TION ASSIST still detects typical indicators of
fatigue or increasing lapses in concentration.
Vehicles with COMAND multimedia system:
if a warning appears in the multifunction display, a service station search is performed in the mul-
timedia system. You can select a service station
and navigation to this service station will then
begin. This function can be activated and deac-
tivated in the COMAND multimedia system (see
the Digital Operator's Manual).
204Driving systems
Driving and parking
Traffic Sign Assist
General notes
Traffic Sign Assist displays the maximum speed
permitted to the driver in the instrument cluster.
The data and general traffic regulations stored in
the navigation system are used to determine the
current speed limit.
Traffic Sign Assist is a map-based system, and
for this reason, traffic signs put up temporarily
(e.g. near roadworks) are not detected. There is also no display for changing traffic signs.
Traffic signs with a restriction indicated by an
additional sign (e.g. in wet conditions) are also
shown.
The sign indicating the end of a restriction only
appears with the restriction in the instrument
cluster when:
RThe regulation must be observed with the
restriction, or
RTraffic Sign Assist is unable to determine
whether the restriction applies
If Traffic Sign Assist is unable to determine a
maximum permitted speed from any of the avail-
able sources, no speed limit appears in the
instrument cluster either.
Traffic Sign Assist is not available in all coun-
tries. In this case, display :appears in the
assistance graphic (
Ypage 231).
Important safety notes
Traffic Sign Assist is only an aid and is not always
able to correctly display speed limits. Traffic
signs always have priority over the Traffic Sign
Assist display.
The system may be either functionally impaired
or temporarily unavailable if the information in
the digital street map of the navigation system is
incorrect or out of date.
Instrument cluster display
Displaying the assistance graphic
XCall up the assistance graphic display func-
tion using the on-board computer
(
Ypage 231).
Detected traffic signs appear in the instru-
ment cluster.
Speed limit with unknown restriction
:Maximum permitted speed
;Maximum permitted speed for vehicles for
which the restriction in the additional sign is relevant
=Additional sign for unknown restriction
A maximum permitted speed of 80 mph
(80 km/h) and a speed limit of 60 mph
(60 km/h) with an unknown restriction apply.
The unit for the speed limit (km/h or mph)
depends on the country in which you are driving. It is generally neither shown on the traffic sign
nor on the instrument cluster but must be taken
into account when observing the maximum per-
mitted speed.
Lane Tracking package
General notes
The Lane Tracking package consists of Blind
Spot Assist (Ypage 205) and Lane Keeping
Assist (Ypage 207).
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-
Driving system s205
Driving an d parking
Z
Warning lamp
:Warning lamp
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
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).
If you select the reverse gear, Blind Spot Assist is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
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. The red warning lamp flashes on the
relevant exterior mirror. If the turn signal
remains on, detected vehicles are indicated by
the flashing of the red warning lamp on the exte-
rior mirror. There are no further warning tones.
Activating Blind Spot Assist
XMake sure that Blind Spot Assist is activated
in the on-board computer (Ypage 232).
XTurn the SmartKey to position 2in the igni-
tion lock.
The red warning lamps on the exterior mirrors
light up until the engine is started.
Display in the assistance graphic
When Blind Spot Assist is activated, gray radar
waves propagating backwards appear next to
the vehicle in the assistance display in the mul-
tifunction display (
Ypage 231). Above a speed
of 20 mph (30 km/h), the color of the radar
waves in the assistance graphic changes to
green :. Blind Spot Assist is then ready for use.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection.
This can be accomplished by checking the trailer
lighting. In this event, Blind Spot Assist is deac-
tivated. The Blind
SpotAssistNotAvail‐able When Towing a Trailer See Opera‐tor's Manualmessage appears in the multi-
function display.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in front of
your vehicle by means of multifunction cam-
era :which is attached behind the top of the
windshield. Active Lane Keeping Assist detects
lane markings on the road and can warn you
before you leave your lane unintentionally.
Driving systems207
Driving and parking
Z
This function is available in the range between
40 mph and 120 mph (60 km/hand 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 cannot always clearly
detect lane markings.
In such cases, Lane Keeping Assist can:
Rgive an unnecessary warning
Rnot give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Lane Keeping Assist alerts you.
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.
Lane Keeping Assist can neither reduce the risk of an accident if you fail to adapt your driving
style 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 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
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 highly variable shade conditions on the roadway
Activating/deactivating Lane Keeping
Assist
XTo activate: press button ;.
Indicator lamp :lights up. The Lane Keep‐
ingAssistOnmessage appears in the mul-
tifunction display. If all conditions have been
satisfied, there may be a warning.
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
the lines in the assistance graphics display
(
Ypage 231) are shown in green. Lane Keep-
ing Assist is ready for use.
XTo deactivate: press button;.
Indicator lamp :goes out. Lane Keeping
Assist is deactivated. The Lane Keeping
Assist Offmessage appears in the multi-
function display.
Selecting Standard or Adaptive setting
XIn the DriveAssistmenu on the on-board
computer, select the LaneKeepingAssistfunction (Ypage 233).
XSelectStandardorAdaptive.
Standard
208Driving systems
Driving an d parking
If you select the reverse gear, Active Blind Spot
Assist is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
When Active Blind Spot Assist is activated, gray
radar waves propagating backward appear next
to the vehicle in the assistance display in the
multifunction display. Above a speed of 20 mph
(30 km/h), the color of the radar waves in the
assistance display changes to green;. Active
Blind Spot Assist is then ready for use.
Visual and acoustic collision warning
If you switch on the turn signals to change lanes
and a vehicle is detected in the side monitoring
range, you receive a visual and acoustic collision
warning. You will then hear a double warning
tone and 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.
Course-correcting brake application
If Active Blind Spot Assist detects a risk of a lat-
eral collision in the monitoring range, a course-
correcting brake application is carried out. This
is meant to assist you in avoiding a collision.
GWARNING
A course-correcting brake application cannot always prevent a collision. There is a risk of an
accident.
Always steer, brake or accelerate yourself,
especially if Active Blind Spot Assist warns
you or makes a course-correcting brake appli-
cation. Always maintain a safe distance at the
sides. If a course-correcting brake application occurs,
red warning lamp
:flashes in the exterior mir-
ror and a double warning tone sounds. In addi-
tion, a display underlining the danger of a side
collision appears in the multifunction display.
In very rare cases, the system may make an
inappropriate brake application. A course-cor-
recting brake application may be interrupted at
any time by countersteering slightly or acceler-
ating.
The course-correcting brake application is avail-
able in the speed range between 20 mph
(30 km/h) and 120 mph (200 km/h).
Either no braking application, or a course-cor-
recting brake application adapted to the driving situation occurs if:
Rthere are vehicles or obstacles, e.g. crash
barriers, located on both sides of your vehicle.
Ra vehicle approaches you too closely at the
side.
Ryou have adopted a sporty driving style with
high cornering speeds.
Ryou clearly brake or accelerate.
Ra driving safety system intervenes, e.g. ESP®
or PRE-SAFE®Brake.
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 is
activated in the on-board computer
(
Ypage 232).
XSwitch on the ignition.
Warning lamps :in the exterior mirrors light
up red for approximately 1.5 seconds.
Gray radar waves propagating backwards
appear next to the vehicle in the assistance
graphic in the multifunction display ;.
Above a speed of 20 mph (30 km/h), the color
of the radar waves in the assistance display
changes to green ;. Active Blind Spot Assist
is then ready for use.
Driving systems211
Driving and parking
Z
Lane-correcting brake application
If you leave your lane, under certain circumstan-
ces the vehicle will brake briefly on one side.
This is meant to assist you in bringing the vehicle
back to the original lane.
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.
If a lane-correcting brake application occurs,
display :appears in the multifunction display.
The brake application also slightly reduces vehi-
cle speed.
A lane-correcting brake application can be made
after driving over a lane marking recognized as
being solid or broken. Before this, a warning
must be given by means of intermittent vibration
in the steering wheel. In addition, a lane with
lane markings on both sides must have been
detected.
In the case of a broken lane marking being
detected, a lane-correcting brake application
can only be made if a vehicle has been detected
in the adjacent lane. Oncoming vehicles, over-
taking vehicles and vehicles in adjacent lanes
can be detected.
A further lane-correcting brake application can
only occur after your vehicle has returned to the
original lane.
No lane-correcting brake application occurs if:
Ryou clearly and actively steer, brake or accel-
erate.
Ryou cut the corner on a sharp bend
Ryou have switched on the turn signal
Ra driving safety system intervenes, e.g. ESP®,
PRE-SAFE®Brake or Active Blind Spot Assist
Ryou have adopted a sporty driving style with
high cornering speeds or high rates of accel-
eration
RESP®is switched off
Rthe transmission is not in position h.
Ron vehicles with a trailer tow hitch, the elec-
trical connection to the trailer has been cor-
rect
ly established
Ra loss of tire pressure or a defective tire has
been detected and displayed.
Ran obstacle has been detected in the lane in
which you are driving
Active Lane Keeping Assist may not detect other
road users or traffic situations. An inappropriate
brake application may be interrupted at any time
if you:
Rsteer slightly in the opposite direction
Rswitch on the turn signal
Ryou brake or accelerate significantly.
A lane-correcting brake application is interrup-
ted automatically if:
Ra driving safety system intervenes, e.g. ESP®,
PRE-SAFE®Brake or Active Blind Spot Assist
Rlane markings are no longer detected
Activating/deactivating Active Lane
Keeping Assist
XTo activate: press button ;.
Indicator lamp :lights up. The Lane Keep‐
ingAssistOnmessage appears in the mul-
tifunction display. If all conditions have been
satisfied, a warning or steering intervention
may be made.
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
Driving systems213
Driving and parking
Z
the lines on the assistance graphic display are
shown in green (Ypage 231). Active Lane
Keeping Assist is ready for use.
XTo deactivate: press button;.
Indicator lamp :goes out. The Active Lane
Keeping Assist is deactivated. The Lane
Keeping Assist Offmessage appears in
the multifunction display.
Selecting Standard or Adaptive setting
XIn the DriveAssistmenu on the on-board
computer, select the Active Lane Keep‐
ing Assistfunction (Ypage 233).
XSelect settingStandardorAdaptive.
When Standardis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time
Ra driving safety system intervenes, such as
ABS, BAS or ESP®
When Adaptiveis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event, the warnings are suppressed for a certain
period of time.
Ra driving safety system intervenes, e.g.
ABS, BAS or ESP®
Ryou accelerate hard, e.g. kickdown.
Ryou brake hard
Ryou steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly
Ryou cut the corner on a sharp bend
To ensure that you are warned only when nec-
essary and in good time if you cross the lane
markings, the system detects certain conditions
and warns you accordingly.
The warning vibration occurs earlier if:
Ryou approach the outer lane marking on a
bend
Rthe road has very wide lanes, e.g. a freeway
Rthe system detects solid lane markings
The warning vibration occurs later if:
Rthe road has narrow lanes
Ryou cut the corner on a bend
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection. This can be accomplished by checking the trailer
lighting.
Towing a trailer
Important safety notes
GWARNING
Installing an unsuitable ball coupling may
result in overloading of the trailer tow hitch
and the rear axle. This applies especially if the ball coupling in question is longer or angled
differently. This could seriously impair the
driving characteristics and the trailer can
come loose. There is a risk of an accident.
You should only ever install a ball coupling
that has the permissible dimensions and that
is designed to meet your trailer-towing
requirements. Do not modify the ball coupling
or the trailer tow hitch.
You will find the values approved by the manu-
facturer on the vehicle identification plates and
those for the towing vehicle under "Technical
data" (
Ypage 384).
GWARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi- cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary.
!If you have a trailer tow hitch retrofitted,
changes to the engine cooling system may be
necessary, depending on the vehicle type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
The installation of a trailer tow hitch is only per-
missible if a towing weight is specified in your
vehicle documents. If this is not the case, then
the vehicle is not approved for the towing of a
trailer.
214Towing a trailer
Driving an d parking
Important safety notes
GWARNING
If you operate information systems and com-
munication equipmen tintegrate din th evehi-
cle when driving ,you may be distracte dfrom
th etraffic situation .You could also lose con-
trol of th evehicle. Ther eis aris kof an acci-
dent.
Only operate this equipmen twhen th etraffic
situation permits. If you are no tsur ethat this
is possible ,park th evehicl epayin gattention
to traffic condition sand operate th eequip-
men twhen th evehicl eis stationary.
You must observ eth elegal requirements for th e
country in whic hyou are currentl ydriving when
operating th eon-board computer.
GWARNIN G
If th einstrumen tcluste rhas faile dor mal-
functioned, you may no trecognize function
restriction sin systems relevan tto safety. The
operating safet yof your vehicl emay be
impaired .Ther eis aris kof an accident.
Drive on carefully. Hav eth evehicl echecke d
at aqualified specialist workshop immedi-
ately.
If th eoperating safet yof your vehicl eis
impaired ,pull ove ras soo nas it is saf eto do so.
Contac t aqualified specialist workshop.
The on-board computer only shows message sor
warning sfrom certain systems in th emultifunc-
tion display. You should therefor emak esur e
your vehicl eis operating safely at all times .
Fo ran overview, see th einstrumen tpanel illus-
tration (
Ypage 37).
Hybrid vehicles: makesur ethat you read th e
separat eoperating instructions. Otherwise, you
may no trecognize dangers.
Displays and operation
Instrument cluster lighting
The lighting in th einstrumen tcluster, in th edis-
plays and th econtrol sin th evehicl einterior can
be adjusted usin gbrightness control knob :.
XTurn brightness control knob :up or down .
If you tur nth eligh tswitch (Ypage 112) to th e
T, ÃorL position ,th ebrightness
will depend upon th ebrightness of th eambi -
en tlight.
iThe ligh tsensor in th einstrumen tcluste r
automatically control sth ebrightness of th e
multifunction display.
In daylight, th edisplays in th einstrumen t
cluste rare illuminated. Adimming function is
no tpossible in daylight.
Speedometer with segments
The speedometer is divided int osegments
depending on th eequipment.
The segments in th espeedometer indicat e
whic hspee drange is available.
RCruis econtrol activated (Ypage 169):
The segments ligh tup from th estore dspee d
to th een dof th escale.
RDistanc ePilot DISTRONI Cis activated
(Ypage 172):
On eor two segments in th eset spee drange
ligh tup.
RDistanc ePilot DISTRONI Cdetects avehicl ein
fron tmoving mor eslowly than th estore d
speed:
The segments between th espee dof th evehi-
cle in fron tand th estore dspee dligh tup.
220Displays and operation
On-board computer and displays