
Lane Keeping Assist does not keep your vehicle
in its lane.
The system may be impaired or may not function
if:
Rif the vehicle is incorrectly loaded
(Ypage 212)
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 highly variable shade conditions on
the road
A warning may be given if a front wheel passes
over a lane marking. In addition, a warning tone
sounds and the Ãindicator lamp in the
instrument cluster flashes red.
Activating/deactivating Lane Keeping
Assist
Lane Keeping Assist is automatically activated
when you start the engine.
XTo deactivate: press thejbutton in the
center console (Ypage 35).
On vehicles without steering wheel but-
tons:
OFF
flashes briefly in the display and the Ã
indicator lamp in the instrument cluster
flashes yellow and then lights up continu-
ously.
On vehicles with steering wheel buttons:
The Lane
Keep.AssistDeactivatedmes-
sage appears in the display and the Ã
indicator lamp in the instrument cluster
flashes yellow and then lights up continu-
ously. Lane Keeping Assist is deactivated.
XTo activate:
press thejbutton in the
center console again (Ypage 35).
On vehicles without steering wheel but-
tons:
on
flashes briefly in the display and the Ã
indicator lamp in the instrument cluster goes
out. If a lane marking is detected, the Ã
indicator lamp lights up green.
On vehicles with steering wheel buttons:
The Lane Keep. Assist Activated
mes-
sage appears in the display and the Ã
indicator lamp in the instrument cluster goes
out. If a lane marking is detected, the Ã
indicator lamp lights up green.
Lane Keeping Assist is activated.
A Lane Keeping Assist warning is suppressed if:
Ra driving safety system intervenes, such as
ABS, BAS or ESP®.
Ryou have set the turn signal and a lane change is detected. In this case, the warnings are
suppressed for a certain period of time.
Ryou accelerate hard, e.g. kickdown on vehi-
cles with an automatic transmission.
Ryou brake hard.
Ryou steer actively, e.g. swerve to avoid an
obstacle or change lane quickly.
Ryou cut the corner on a sharp bend.
In order that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, the system recognizes certain conditions
and warns you accordingly.
Lane Keeping Assist warns you earlier if:
Ryou approach the outer lane marking on a
bend.
Rthe road has very wide lanes, e.g. a freeway.
Rthe system recognizes solid lane markings.
Warnings are given later if:
Rthe road has narrow lanes.
Ryou cut the corner on a bend.
All-wheel drive
Important safety notes
!Never tow the vehicle with one axle raised.
This may damage the transfer case. Damage
of this sort is not covered by the Mercedes-
Benz Limited Warranty. All wheels must
Driving systems147
Driving and parking
Z

remain either on the ground or be fully raised.
Observe the instructions for towing the vehi-
cle with all wheels in full contact with the
ground.
!A function or performance test should only
be carried out on a two-axle dynamometer.
Before you operate the vehicle on such a
dynamometer, please consult a qualified
workshop. You could otherwise damage the
drive train or the brake system.
If you fail to adapt your driving style or if you are
inattentive, the all-wheel drive system can nei-
ther reduce the risk of an accident nor override
the laws of physics. The all-wheel drive system
cannot take road, weather and traffic conditions
into account. The all-wheel drive system is only
an aid. You are responsible for the distance to
the vehicle in front, for vehicle speed and for
braking in good time.
4ETS ensures permanent drive for all four
wheels, and together with ESP
®it improves the
vehicle's traction.
If a driven wheel spins due to lack of traction:
RWhen pulling away, make use of the traction
control integrated in ESP®. Depress the
accelerator pedal as far as necessary.
RWhile driving, slowly take your foot off the
accelerator pedal
In wintry driving conditions, always use winter
tires (M+S tires) and if necessary, snow chains
(
Ypage 249). This is the only way to get the full
benefit from the all-wheel drive system.
For information on "Driving off-road", see
(
Ypage 137).
Engaging all-wheel drive
Conditions for engaging/disengaging
All-wheel drive can only be engaged or disen-
gaged if:
Rthe engine is running
Rthe vehicle is stationary
If it is not possible to engage all-wheel-drive:
Rmove the selector lever to position N
Rrelease the brake pedal
Rpress the;button
Rmove the selector lever from Nto Dor R
Engaging/disengaging all-wheel drive
XTo engage/disengage: press the;but-
ton.
The indicator lamp in the ;button flashes.
The h and: indicator lamps light up in
the instrument cluster. ESP
®and ASR are
deactivated for the duration of the engaging/ disengaging process.
If the engaging/disengaging process is suc-
cessful, the hand: indicator lamps in
the instrument cluster go out and ESP
®and
ASR are reactivated.
If the indicator lamp in the ;button is lit,
all-wheel drive is engaged. On vehicles with
steering-wheel buttons, the display then
shows the following message: Four-wheel
drive active.
If the engaging/disengaging process fails, the indicator lamp in the ;button flashes
three times briefly. One of the gear change
conditions was not fulfilled.
As long as the indicator lamp in the ;button
is flashing, you can cancel the engaging/disen-
gaging process by pressing the ;again.
iIf the LOW RANGE transmission ratio
(Ypage 148) is engaged, all-wheel drive can-
not be disengaged.
LOW RANGE transmission ratio
General notes
The LOW RANGE transmission ratio assists you
when driving on difficult terrain. If you engage
LOW RANGE, the engine's performance charac-
teristics and the automatic transmission's shift-
ing characteristics are adjusted accordingly.
The transmission ratio from the engine to the
wheels is around 40% lower than in the on-road position. This increases the drive torque.
148Driving systems
Driving and parking

Conditions for engaging/disengaging
LOW RANGE can only be engaged or disengaged
if:
Rthe engine is running
Rthe vehicle is stationary
Rthe brake pedal is depressed
Rthe selector lever of the automatic transmis-
sion is in positionPor N
Rall-wheel drive is engaged
Engaging and disengaging LOW RANGE
:Engages and disengages LOW RANGE
XTo engage or disengage: press button:
or ;.
The + indicator lamp flashes in the instru-
ment cluster for the duration of the engaging/
disengaging process.
If the engaging/disengaging process is suc-
cessful:
Rand LOW RANGE is engaged, the +indi-
cator lamp lights up.
Rand LOW RANGE is disengaged, the +
indicator lamp goes out.
As long as the +indicator lamp is flashing,
you can cancel the engaging/disengaging
process by pressing button :or; again.
If the engaging/disengaging process fails, the + indicator lamp briefly flashes three
times. One of the gear change conditions was
not fulfilled.
DSR (Downhill Speed Regulation)
Important safety notes
Observe the notes on braking in the section on
"Driving and parking". If you fail to adapt your
driving style or you are inattentive, DSR can nei-
ther reduce the risk of accident nor override the laws of physics. DSR cannot take road, weather
and traffic conditions into account. DSR is only
an aid. You are responsible for the distance to
the vehicle in front, for vehicle speed and for
braking in good time.
General notes
DSR supports you with the LOW RANGE trans-
mission ratio when you are driving downhill off-
road and on construction sites. DSR maintains a
preset speed for you on downhill gradients by
applying the brakes as required. Maintaining the
speed is dependent on the road surface condi-
tions and the downhill gradient and cannot
therefore be guaranteed in all situations.
You can set the speed to between 2.5 mph
(4 km/h) and 11 mph (18 km/h) using the brake
and accelerator pedals or the cruise control
lever.
RIf the vehicle is stationary, or its speed is less
than 2.5 mph (4 km/h) the speed is set to
2.5 mph (4 km/h).
RIf you drive faster than 11 mph (18 km/h) off-
road, DSR switches to standby mode. DSR
remains activated, but does not brake auto-
matically.
RIf you drive downhill slower than 11 mph
(18 km/h), DSR sets the speed to the previ-
ously set speed.
RDSR switches off automatically if you drive
faster than 28 mph (45 km/h).
Cruise control lever
:Activates DSR and stores the current or
higher speed
;Activates DSR and stores the current speed
=Activates DSR and stores the current or
lower speed
?Deactivates DSR
The cruise control lever is the uppermost lever
on the left of the steering column. For as long as
Driving systems149
Driving and parking
Z

the LOW RANGE transmission ratio is engaged,
only use the cruise control lever to operate DSR.
When the LOW RANGE transmission ratio is dis-
engaged, use cruise control.
Activation conditions
In order to activate DSR, both activation condi-
tions must be fulfilled:
RThe LOW RANGE transmission ratio is
engaged. The+indicator lamp in the
instrument cluster lights up.
RThe vehicle is stationary or you are not driving faster than 11 mph (18 km/h).
Activating DSR
You can activate DSR when the vehicle is sta-
tionary or moving.
XBrake or accelerate the vehicle to the
required speed between 2.5 mph (4 km/h)
and 11 mph (18 km/h).
XBriefly push the cruise control lever up :or
down =.
or
XBriefly pull the cruise control lever towards
you ;.
XRelease the brake or accelerator pedal.
The current speed is stored. When the vehicle
is stationary, the speed is stored at 2.5
(4 km/h). DSR maintains the stored speed on
the downhill gradient and brakes automati-
cally.
When DSR is activated and the vehicle pulls
away, accelerates or brakes, the speed set cor-
responds to the speed at which the accelerator
or brake pedal is released. Thi s i
s only the case
if you are not driving faster than 11 mph
(18 km/h).
DSR status indicator in the on-board com-
puter
Vehicles with steering wheel buttons
LOW RANGE is engaged
RThe DSRmessage is displayed in the status
area of the on-board computer.
RDSR can be activated.
DSR is activated
RThe DSRmessage and the set speed are dis-
played in the status area of the on-board com-
puter. DSR is activated but is not intervening
RYou are driving at between 11 mph (18 km/h)
and 28 mph (45 km/h).
RThe
DSRmessage is displayed in the status
area of the on-board computer. Also, the
speed 11 mph (18 km/h) flashes.
DSR is activated but is not intervening
RYou are driving faster than 28 mph (45 km/h).
RThe DSRmessage is displayed in the status
area of the on-board computer. Also, the ---
message is displayed for 5 seconds.
DSR is activated but is not intervening
RThe DSR---message is displayed in the sta-
tus area of the on-board computer.
There is a malfunction in the Electronic Brak-
ing System (EBS). Visit a qualified specialist
workshop.
Setting the speed whilst driving downhill
You can set the speed to between 2.5 mph
(4 km/h) and 11 mph (18 km/h) using the brake
and accelerator pedals or the cruise control
lever.
XBrake or accelerate the vehicle to the
required speed on the downhill gradient.
XRelease the brake or accelerator pedal. The
current speed is stored.
or
XBriefly push the cruise control lever
upwards :to increase the speed or down-
wards =to reduce the speed.
The last speed stored is increased or reduced
incrementally.
XRelease the cruise control lever. The current
speed is stored.
or
XPress and hold the cruise control lever up :
or down =until the desired speed has been
reached.
XRelease the cruise control lever.
The current speed is stored.
iIt may take a moment before the vehicle
brakes to the set speed. Take this delay into
account when setting the speed with the
cruise control lever.
150Driving system s
Driving an d parking

Deactivating DSR
XBriefly press thecruise control lever for-
ward s?.
or
XAccelerate and drive faste rthan 28 mph
(45 km/h).
DS Rdeactivates automatically if:
Ryou are drivin gfaste rthan 28 mph (45 km/h).
Ryou disengage th eLO WRANGE transmissio n
ratio.
Rthere is amalfunction in th eES P®or AB Ssys-
tem.
PARKTRONIC
General notes
PARKTRONI Cis an electronic parkin gaid. The
system is equipped wit hultrasonic sensor sin
th efron tand rea rbumpers to monitor th eare a
around your vehicle. PARKTRONI Cindicate svis -
ually and audibl yth edistanc ebetween your
vehicl eand an object.
Your vehicl efeatures tw oseparat esoun demit-
ters wit hdifferen tfrequencies fo rth ewarnin g
tones. The warnin granges in fron tof and behin d
th evehicl eare indicate dby differen twarnin g
tones.
PARKTRONI Cis activated automatically when
you:
Rtur nth eke yto position 2in th eignition loc k
Rrelease theparkin gbrak eand
Rmov eth eselector lever to D,Nor R.
PARKTRONI Cis deactivated at speeds abov e
11 mph (18 km/h). PARKTRONI Cis reactivated
at speeds belo w10 mph (16 km/h).
Important safet ynotes
PARKTRONI Cis only an aid. It canno treplac e
your own awareness of th eimmediat esurround -
ings. You are responsibl efo rsaf emaneuvering,
parkin gand pullin gaway. Whe nmaneuvering,
parkin gand pullin gaway, mak esur ethat there
are no persons, animals or objects in th emaneu-
verin garea.
!Pay particular attention to obstacles abov e
or belo wthesensor swhen parking, suc has
flower pot sor trailer towbars. PARKTRONI C
doe sno trecogniz esuc hobjects when they are in th
eimmediat evicinit yof th evehicle.
You could damage th evehicl eor objects .
PARKTRONI Ccan suffer interferenc efrom:
Rultrasonic source ssuc has atruck's
compressed-air brakes, an automati ccar
wash or apneumati cdrill
Rattachments to th evehicle, e.g. rea rmoun-
te dracks
Rnumber plates (vehicle license plates) that
are no taffixed flat against th ebumper
Rdirty or icy sensor s
Remove adetachable trailer couplin gif it is no
longer required. PARKTRONI Cmeasures th e
minimum detection range to an obstacle from
th ebumper, no tth eball coupling.
Range of th esensor s
PARKTRONI Cdoe sno taccoun tfo robstacles
that are :
Rbeneathits detection range, e.g. persons, ani -
mals or objects
Rabov eits detection range, e.g. overhangin g
loads ,overhang sor truck loading ramps
The sensor smus tbe free of dirt, ice or slush.
Otherwise ,they canno tfunction correctly.
Driving systems15 1
Driving an d parking
Z

Selector lever posi-
tionMonitoring
DFront area
Ror NFront and rear area
PNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the vehi-
cle's distance from the obstacle.
From the:
Rsixth segment, an intermittent warning tone
sounds for approximately 2 seconds.
Rseventh segment, a continuous warning tone
sounds. This indicates that you have now
reached the minimum distance.
Roll-back warning
PARKTRONIC automatically monitors the area
behind the vehicle if the vehicle begins to roll
backwards without reverse gear engaged, e.g.
after stopping on an uphill gradient.
If PARKTRONIC recognizes an obstacle at a dis-
tance of at most 31 in (80 cm), all the segments
in the warning displays light up. A continuous
warning tone also sounds as the vehicle
approaches the obstacle and for a further
2 seconds after the vehicle has come to a halt.
Activating/deactivating PARKTRONIC
XPress the fbutton.
If PARKTRONIC is deactivated, the indicator
lamp in the switch lights up.
Towing a trailer
PARKTRONIC detects a coupled trailer if your
vehicle is equipped with the corresponding elec-
trical installations for trailer towing.
PARKTRONIC is deactivated for the rear area
when you establish an electrical connection
between your vehicle and a trailer. If you use an
adapter for the socket, remove it from the
socket after detaching the trailer. Otherwise,
PARKTRONIC remains deactivated for the rear
area.
Remove a detachable trailer coupling if it is no
longer required. PARKTRONIC measures the
minimum detection range to an obstacle from
the bumper, not the ball coupling.
Driving systems153
Driving and parking
Z

Problems with PARKTRONIC
ProblemPossible causes/consequences andMSolutions
Only the red segments in
the PARKTRONIC warn-
ing displays are lit.
A warning tone also
sounds for approx-
imately 2 seconds.
PARKTRONIC is deacti-
vated after approx-
imately 20 seconds.
The indicator lamp of the
f button lights up
and the red segments in
the PARKTRONIC warn-
ing display go out.PARKTRONIC has malfunctioned and has switched itself off.
XIf problems persist, have PARKTRONIC checked at a qualified spe- cialist workshop.
The PARKTRONIC warn-
ing displays implausible
distances.
For example, all the seg-
ments may be lit even
though there is no obsta-
cle present.The PARKTRONIC sensors are dirty or iced up.
XClean the PARKTRONIC sensors (Ypage 236).
XTurn the key to position 2again in the ignition lock.
The license plate or other parts attached near the sensors may not be
secured correctly.
XCheck the license plate and attachment parts near the sensors for
correct seating.
An external radio or ultrasonic source may be causing interference.
XCheck PARKTRONIC functions in a different location.
Rear view camera
Important safety notes
The rear view camera is only an aid. It cannot
replace your own awareness of the immediate
surroundings. You are responsible for safe
maneuvering, parking and pulling away. When
maneuvering, parking and pulling away, make
sure that there are no persons, animals or
objects in the maneuvering area.
The rear view camera is a visual parking aid.
Information on operation can be found in the
separate Audio 15 supplement.
The camera is in the middle of the roof above the
high-mounted brake lamp (
Ypage 236).
You can find information on cleaning the camera
in the "Maintenance and care" section
(
Ypage 236).
Working mode
ADR (working speed governor)
General notes
When activated, ADR automatically increases
the engine speed to a preset speed or a speed
you have set.
iAfter a cold start, the idling speed of the
engine is increased automatically. If the pre-
set working speed is lower than the increased idling speed, the working speed is only
reached once the engine has completed the
warm-up phase.
It is only possible to activate ADR with the
vehicle stationary and the parking brake
applied.
The selector lever of the automatic transmis-
sion must be in position P.
154Working mode
Driving and parking

Switching ADR on and off
XTo activate:press upper section :of the
E switch while the engine is running.
The indicator lamp in the switch comes on.
The K indicator lamp in the instrument
cluster lights up or the display shows the fol-
lowing message: Operating speed gover‐
nor active.
XTo deactivate:press lower section ;of the
E switch while the engine is running.
The indicator lamp in the switch goes out.
ADR is automatically deactivated if:
Ryou release the parking brake.
Rthe brake pedal is depressed.
Rthe vehicle moves.
Rthe control unit detects a malfunction.
Setting the working speed
XActivate ADR.
XTo increase: press theEbutton.
XTo decrease: press theFbutton.
Towing a trailer
Notes on trailer towing
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.
GWARNING
If you use a ball coupling that is not approved
for your vehicle, it may cause excessive strain
on the trailer tow hitch. This can cause dam-
age to the vehicle and the trailer may come
loose during the journey. The handling may be
impaired and the rear axle may be overloaded.
This may lead to an accident involving serious
or even fatal injury.
Therefore note the following:
ROnly install a ball coupling that is approved for your vehicle.
RBefore the journey, make sure that the ballcoupling is correctly installed and secured.
To do this, observe the operating instruc-
tions of the ball coupling manufacturer.
RDo not make any modifications to the ball
coupling or the trailer tow hitch.
You must observe the operating instructions
of the trailer tow hitch or ball coupling manu-
facturer.
GWARNING
If the ball coupling is not correctly installed
and secured, it could come loose while driving and endanger other road users. There is a risk
of an accident and injury.
Towing a trailer155
Driving and parking
Z