
is adapted accordingly and the driver is warned
earlier.
When ATTENTION ASSIST is deactivated, the
Àsymbol and OFF appear in the multifunc-
tion display in the assistance display when the
engine is running.
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:TakeaBreak!
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. If you do not take
a break, you will be warned again after
15 minutes at the earliest. This will only happen
if ATTENTION ASSIST still detects typical indi-
cators of fatigue or increasing lapses in concen-
tration.
Vehicles with COMAND: if a warning is issued
in the multifunction display, a service station
search is performed in COMAND. You can select a service station and navigation to this service
station will then begin. This function can be acti-
vated and deactivated in COMAND.
Traffic Sign Assist
General notes
Traffic Sign Assist displays the maximum speed
permitted to the driver in the instrument cluster.
The data stored in the navigation system and
general traffic regulations are used to determine
the current speed limit.
As Traffic Sign Assist is a map-based system,
traffic signs put up temporarily (e.g. near road-
works) are not detected. If a traffic sign that is relevant to your vehicle is
passed, the display of the speed limits is upda-
ted.
Traffic signs with a restriction indicated by an
additional sign (e.g. in wet conditions) are also
shown.
The traffic signs are only displayed with the
restrictions if:
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 is displayed in the
instrument cluster either.
Traffic Sign Assist is not available in all coun-
tries. In this case, symbol :is shown in the
assistance graphic display (
Ypage 237).
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 graphics display func-
tion using the on-board computer
(
Ypage 237).
XSelect the Traffic Sign Assist display.
Detected traffic signs are displayed in the
instrument cluster.
206Driving systems
Driving and parking 

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 indicator lamp lights up yellow in
the exterior mirrors and the Blind Spot
Assist Not Available When Towing aTrailer See Operator's Manualmessage
appears in the multifunction display.
iYou can deactivate the indicator lamps in
the exterior mirrors.
To do so, switch off Blind Spot Assist when:
Rthe SmartKey is in position 2in the ignition
lock
Rthe engine is not running
Lane Keeping Assist
General notes
:Lane Keeping Assist camera
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 second s.
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 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
Driving systems209
Driving and parking
Z 

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 onthe roadway
Rno vehicle is detected in the adjacent lane andthere are broken lane markings
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 second s.
In orde r that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, 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 highway
Rthe system detects solid lane markings
The warning vibration occurs later if:
Rthe road has narrow lanes
Ryou cut the corner on a bend
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 does not detect
traffic conditions or road users. In very rare
cases, the system may make an inappropriate
brake application, e.g. after intentionally driv-
ing 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
there is sufficient distance on the side for
other traffic or obstacles.
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.
If a lane-correcting brake application occurs,
display :appears in the multifunction display.
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 be recog-
nized.
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. The following vehicles can
have an influence on brake application: oncom-
ing traffic, vehicles that are overtaking and vehi-
cles that are driving parallel to your vehicle.
iA 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.
214Driving systems
Driving and parking 

Display messagesPossible causes/consequences andMSolutions
LOW RANGE ShiftingCanceled PleaseReactivate
The gear chang eprocess was no tcarrie dout .
XEnsur ethat all gear chang econdition sare fulfilled and carry out th e
gear chang eprocess again .
LOW RANGE Sto pApply ParkingBrakeAwarning tone also sounds. The gear chang eprocess has no tbeen
completed. LOW RANGE is in th eneutral position .There is no con-
nection between th eengin eand th edrive wheels.
!Do no tdrive any further. You could otherwise damag eth evehi-
cle's drive train .
XStop thevehicle. Tak eint oaccoun tth eroa dand traffic condition s
when doin gthis.
XDepress th eelectric parking brak e (Ypage 160).
XCarryout th egear chang eprocess again .
If th egear chang eprocess has been carrie dout ,th eLOW RANGE
Sto pApply Parkin gBrakemessage disappears.
Driving dynamics display in the
COMAND display (vehicles with the Off-
roa d Engineering-package)
Genera lnotes
The drivin gdynamic sdisplay allows you to see
th eselected drive progra mand additional infor-
mation about th evehicle's operating status in
th eCOMAND display.
:Drive progra mselected
;Status of th edifferential loc kfor th etransfer
cas e
=Accelerato rpedal position shown in %
?Brake pedal position shown in %
ACondition of theLOW RANGE offroa dgear
BAngle of inclination
CSteering angle
DUphill or downhill gradien tin percentage
ELevel control
FCompass wit hangle scale
Activating th edrivin gdynamics displa y
XSwitchon COMAND .You can fin dfurther
information in th eseparat eCOMAND operat-
ing instructions.
XPress butto n:.
The drivin gdynamic sdisplay appear sin th e
COMAND display.
Towing a trailer
Import ant safety notes
GWARNIN G
Installin gan unsuitable ball couplin gmay
result in overloadin gof th etrailer to whitch
and th erear axle. This applie sespecially if th e
ball couplin gin question is longer or angled
differently. This could seriously impair th e
Towing a trailer221
Driving and parking
Z 

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 thatis 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 387).
GWARNING
If the ball coupling is not installed correctly or not secured with the bolt provided and the
corresponding spring cotter, the trailer may
come loose. There is a risk of an accident.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter.
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.
Please observe the manufacturer's operating
instructions for the trailer coupling if a detach-
able trailer coupling is used.
Couple and uncouple the trailer carefully. If you
do not couple the trailer to the towing vehicle
correctly, the trailer could become detached.
Make sure that the following values are not
exceeded:
Rthe permissible trailer drawbar noseweight
Rthe permissible trailer load
Rthe permissible rear axle load of the towing
vehicle
Rthe maximum permissible gross vehicle
weight of both the towing vehicle and the
trailer The applicable permissible values, which must
not be exceeded, can be found:
Rin the vehicle documents
Ron the identification plates for the trailer tow
hitch and the trailer
Ron the vehicle identification plate
If the values differ, the lowest value applies.
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
The vehicle/trailer combination:
Ris heavier
Ris restricted in its acceleration and gradient-
climbing capability
Rhas an increased braking distance
Ris affected more by strong crosswinds
Rdemands more sensitive steering
Rhas a larger turning circle
This could impair the handling characteristics.
When towing a trailer, always adjust your speed
to the current road and weather conditions. Do
not exceed the maximum permissible speed for
your vehicle/trailer combination.
Notes on towing a trailer
General notes
!If you have a trailer tow hitch retrofitted,
changes to the cooling system and drive train
may be necessary, depending on the vehicle
type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
RDo not exceed the legally prescribed maxi-
mum speed for vehicle/trailer combinations
in the relevant country.
This lowers the risk of an accident.
ROnly install an approved trailer coupling on
your vehicle.
Further information on availability and on
installation is available from any authorized
Mercedes-Benz Center.
RThe bumpers of your vehicle are not suitable
for installing detachable trailer couplings.
222Towing a trailer
Driving and parking 

RDo not install hired trailer couplings or other
detachable trailer couplings on the bumpers
of your vehicle.
RIf you no longer need the ball coupling,
remove it from the ball coupling recess. This
will reduce the risk of damage to the ball cou-
pling.
When towing a trailer, set the tire pressure on
the rear axle of the towing vehicle for the max-
imum load. You will find the values in the tire
pressure table in the fuel filler flap of the vehicle (
Ypage 364).
Please note that when towing a trailer, the fol-
lowing driving systems have limited availability
or are not available at all:
RParking Assist PARKTRONIC (Ypage 190)
RBlind Spot Assist (Ypage 207)
RActive Lane Keeping Assist (Ypage 213)
On vehicles without level control, the height of
the ball coupling will alter according to the load
placed on the vehicle. If necessary, use a trailer
with a height-adjustable drawbar.
You will find installing dimensions and loads
under "Technical data" (
Ypage 387).
Driving tips
Observe the information on ESP®trailer stabili-
zation (Ypage 68) and on pulling away with a
trailer (Ypage 141).
The maximum permissible speed for vehicle/
trailer combinations depends on the type of
trailer. Before beginning the journey, check the
trailer's documents to see what the maximum
permissible speed is. Observe the legally pre-
scribed maximum speed in the relevant country.
For certain Mercedes-Benz vehicles, the maxi-
mum permissible rear axle load is increased
when towing a trailer. See "Technical data" to
find out whether this applies to your vehicle
(
Ypage 387). If you utilize any of the added
maximum rear axle load when towing a trailer,
the vehicle/trailer combination may not exceed
a maximum speed of 60 mph (100 km/h) for
reasons concerning the operating permit. This
also applies in countries in which the permissi-
ble maximum speed for vehicle/trailer combi-
nations is above 60 mph (100 km/h).
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer. Use the left-hand steering wheel paddle shifter
to shift into a lowe
r g
ear in good time on long
and steep downhill gradients.
This also applies if you have activated cruise
control or Distance Pilot DISTRONIC.
This will use the braking effect of the engine, so that less braking will be required to maintain the
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly. If you need additional
braking, depress the brake pedal repeatedly
rather than continuously.
Driving tips
If the trailer swings from side to side:
XDo not accelerate.
XDo not counter-steer.
XBrake if necessary.
RMaintain a greater distance from the vehicle
in front than when driving without a trailer.
RAvoid braking abruptly. If possible, brake gen-tly at first to allow the trailer to run on. Then,
increase the braking force rapidly.
RThe values given for gradient-climbing capa-
bilities from a standstill refer to sea level.
When driving in mountainous areas, note that
the power output of the engine and, conse-
quently, the vehicle's gradient-climbing capa-
bility, decreases with increasing altitude.
Installing the ball coupling
GWARNING
If the ball coupling is not correctly installed
and secured, it can come loose during the
journey and endanger other road users. There is a risk of an accident and injury.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter.
GWARNING
If the ball coupling is not installed correctly or not secured with the bolt provided and the
corresponding spring cotter, the trailer may
come loose. There is a risk of an accident.
Towing a trailer223
Driving an d parking
Z 

Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed restric-tions. Make sure that your car/trailer combina-
tion complies with the local regulations:
Rin your place of residence
Rin the location to which you are driving
The police and local authorities can provide reli- able information.
Observe the following when towing a trailer:
RTo gain driving experience and to become
accustomed to the new handling characteris-
tics, you should practice the following in a
traffic-free location:
-cornering
-stopping
-backing up
RBefore driving, check:
-trailer tow hitch
-safety switch for braked trailers
-safety chains
-electrical connections
-lights
-wheels
RAdjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
RIf the trailer has electronically controlled
brakes, pull away carefully. Brake manually
using the brake controller and check whether
the brakes function correctly.
RSecure any objects on the trailer to prevent
the cargo from slipping when the vehicle is in
motion.
RWhen you couple up a trailer, check at regular
intervals that the load is firmly secured. If the
tra
iler is equipped with trailer lights and
brakes, check the trailer to ensure that these
are working.
RBear in mind that the handling will be less
stable when towing a trailer than when driving
without one. Avoid sudden steering move-
ments.
RThe vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
RIf possible, do not brake suddenly, but instead depress the brake pedal moderately at first so
that the trailer can activate its brakes. Then
increase the pressure on the brake pedal.
RIf the automatic transmission repeatedly
shifts between gears on uphill or downhill gra-
dients, shift to a lower gear using the left-hand
steering wheel paddle shifter.
A lower gear and lower speed reduce the risk
of engine failure.
RWhen driving downhill, shift to a lower gear toutilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if instal-
led, the trailer brakes.
RIf the coolant temperature increases dramat-
ically while the air-conditioning system is
switched on, switch off the air-conditioning
system.
Coolant heat can also be dissipated by open-
ing the windows and switching the ventilation blower and the interior temperature to the
highest level.
RWhen overtaking, pay particular attention to
the extended length of your vehicle/trailer
combination.
Due to the length of the vehicle/trailer com-
bination, you require additional road space in
relation to the vehicle you are overtaking
before you can change back to the original
lane.
Decoupling a trailer
GWARNING
If you uncouple a trailer with the overrun
brake engaged, you could trap your hand
between the vehicle and the trailer drawbar.
There is a risk of injury.
Do not uncouple a trailer if the overrun brake
is engaged.
GWARNING
Vehicles with level control:
The vehicle is lowered as soon as you discon-
nect the trailer cable. This could result in your
limbs or those of other people that are
between the vehicle body and tires or under-
226Towing a trailer
Driving an d parking 

There is a short delay before a change in outside
temperature appears in the multifunction dis-
play.
Coolant temperature gauge
GWARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
!A display message is shown if the coolant
temperature is too high.
If the coolant temperature is over 248 ‡
(120 †), do not continue driving. The engine
will otherwise be damaged.
The coolant temperature gage is in the instru-
ment cluster on the right-hand side (
Ypage 34).
Under normal operating conditions and with the
specified coolant level, the coolant temperature
may rise to 248 ‡ (120 †).
Operating the on-board computer
Overview
:Multifunction display
;Right control panel
=Left control panel
XTo activate the on-board computer: turn
the SmartKey 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.
Vehicles with the COMAND multimedia system:
you can find further information on the Voice
Control System in the separate operating
instructions.
Vehicles with the Audio 20 multimedia system:
you can find further information on voice-oper-
ated navigation in the manufacturer's operating
instructions.
230Displays and operation
On-board computer and displays