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 max-
imum permissible speed is. Observe the
legally prescribed maximum speed in the rel-
evant country.
For certain Mercedes-Benz vehicles, the max-
imum permissible rear axle load is increased
when towing a trailer. Refer to the "Technical
data" section to find out whether this applies
to your vehicle.
If you utilize any of the added maximum rear
axle load when towing a trailer, the vehicle/
trailer combination may not exceed a maxi-
mum speed of 60 mph (100 km/h) for rea-
sons concerning the operating permit. This
also applies in countries in which the permis-
sible maximum speed for vehicle/trailer com-
binations 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 lower gear in good time
on long and steep downhill gradients.
iThis also applies if you have activated
cruise control.
This will use the braking effect of the engine,
so that less braking will be required to main-
tain the speed. This relieves the load on the
brake system 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
RMaintain a greater distance from the vehi-
cle in front than when driving without a
trailer.
RAvoid braking abruptly. If possible, brake
gently at first to allow the trailer to run on.
Then, increase the braking force rapidly.
RThe values given for gradient-climbing
capabilities from a standstill refer to sea level. When driving in mountainous areas,
note that the power output of the engine
and, consequently, the vehicle's gradient-
climbing capability, decreases with
increasing altitude.
If the trailer swings from side to side:
XDo not accelerate.
XDo not counter-steer.
XBrake if necessary.
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.
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 and secured
correctly the trailer may come loose. There is
a risk of an accident.
Install and secure the ball coupling as descri-
bed in the ball coupling installation instruc-
tions. Make sure that the ball coupling is
installed and secured correctly before every
journey.
230Towing a trailer
Driving and parking
cleaned, remove the ball coupling. The trailer
tow hitch must then not be used to tow a
trailer, as safe operation cannot be guaran-
teed.
Have the entire trailer tow hitch checked at a
qualified specialist workshop.
Coupling up a trailer
!
Do not connect the trailer's brake system
(if featured) to the hydraulic brake system
of the towing vehicle, as the latter is equip-
ped with an anti-lock brake system. Doing
so will result in a loss of function of the
brake systems of both the vehicle and the
trailer.
XShift the transmission to position P.
XApply the vehicle's electric parking brake.
XStart the engine.
XVehicles with AIR BODY CONTROL:
selectComfort driving program or Trailer
off-road program.
XSwitch off the engine.
XClose the doors and tailgate.
XCouple up the trailer.
XEstablish the electrical connection
between the vehicle and the trailer.
XCheck that the trailer lighting system is
working.
XPush the combination switch upwards/
downwards and check whether the corre-
sponding turn signal on the trailer flashes.
A trailer that is connected is recognized only
when the electrical connection is established
correctly and when the lighting system is
working properly. The function of other sys-
tems also depends on this, for example:
RESP®
RPARKTRONIC
RActive Parking Assist
RActive Blind Spot Assist
RActive Lane Keeping Assist
iVehicles with AIR BODY CONTROL: if you
couple up a trailer, the vehicle always
remains at highway level. When coupling up
a trailer, please observe the following:
RUnless highway level has been set man-
ually, the vehicle is automatically low-
ered to highway level. This is the case if a
speed of 5 mph (8 km/h) is reached.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Observe the maximum permissible trailer
dimensions (width and length).
Most U.S. states and all Canadian provinces
require by law:
RSafety chains between the towing vehicle
and the trailer. The chains should be cross-
wound under the trailer drawbar. They must
be fastened to the vehicle's trailer cou-
pling, not to the bumper or the axle.
Leave enough play in the chains to make
tight cornering possible.
RA separate brake system for certain types
of trailer.
RSafety switch for braked trailers. Check the specific legal requirements applicable to
your state.
If the trailer becomes detached from the
towing vehicle, the safety switch applies
the trailer brakes.
Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed
restrictions. Make sure that your car/trailer
combination complies with the local regula-
tions:
Rin your place of residence
Rin the location to which you are driving
The police and local authorities can provide
reliable information.
232Towing a trailer
Driving and parking
Observe the following when towing a trailer:
RTo gain driving experience and to become
accustomed to the new handling charac-
teristics, 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 reg-
ular intervals that the load is firmly secured.
If the trailer 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 driv-
ing without one. Avoid sudden steering
movements.
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 moder-
ately 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
gradients, 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
to utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if
installed, the trailer brakes.
RIf the coolant temperature increases dra-
matically while the air-conditioning system is switched on, switch off the air-condition-
ing system.
Coolant heat can also be dissipated by
opening the windows and switching the
ventilation blower and the interior temper-
ature 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
combination, you require addi
tional 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.
!Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the rebound-
ing of the overrun brake.
Towing a trailer233
Driving and parking
Z
XMake sure that the automatic transmissionis set to position P.
XApply the vehicle's parking brake.
XClose all doors and the tailgate.
XApply the trailer's parking brake.
XRemove the trailer cable and decouple the
trailer.
Removing the ball coupling
XRemove the spring cotter.
XRemove the bolt from the ball coupling
recess.
XRemove the ball coupling from the ball cou-
pling recess.
XClean the ball coupling if it is dirty.
XStow the ball coupling so that it cannot be
thrown around.
Observe the loading guidelines (
Ypage 306)
and the safety notes regarding stowage
spaces (
Ypage 306).
Information on cleaning and care of the trailer
tow hitch (
Ypage 349).
Trailer power supply
The trailer socket of your vehicle is equipped
at the factory with a permanent power supply.
The permanent power supply is supplied via
trailer socket pin 4.
!Accessories with a maximum power con-
sumption of 180 W can be connected to the
permanent power supply.
You must not charge a trailer battery using
the power supply.
The trailer's permanent power supply is
switched off in the event of low vehicle supply
voltage and after six hours at the latest.
A qualified specialist workshop can provide
more information about installing the trailer
electrics.
Permissible trailer loads and trailer
drawbar noseweights
Weight specifications
The gross trailer weight is calculated by add-
ing the weight of the trailer to the weight of
the load and equipment on the trailer.
You will find installing dimensions and loads
under "Technical data" (
Ypage 415).
Loading a trailer
RWhen loading the trailer, make sure that
neither the permissible gross weight of the
trailer nor the gross vehicle weight is
exceeded. The permissible gross vehicle
weight is indicated on the identification
plate on the B-pillar on the driver's side of
the vehicle.
You can find the maximum permissible val-
ues on the type plates of your vehicle and
the trailer. When calculating how much
weight the vehicle and trailer may carry,
pay attention to the respective lowest val-
ues.
RThe trailer drawbar load on the ball coupling
must be added to the rear axle load to avoid
exceeding the permissible gross axle
weight. The permissible gross vehicle
weight is indicated on the identification
plate on the B-pillar on the driver's side of
the vehicle.
iMercedes-Benz recommends a trailer
load where the trailer drawbar noseweight
accounts for 8% to 15% of the trailer's per-
missible gross weight.
iThe weight of other accessories, passen-
gers and loads reduces:
Rthe permissible trailer load
Rthe permissible noseweight that your
vehicle can tow
234Towing a trailer
Driving and parking
The assistance graphic displays the status
of and information from the following driv-
ing systems or driving safety systems:
RDISTRONIC PLUS (Ypage 183)
RTraffic Sign Assist (Ypage 216)
RDistance warning and the autonomous
braking function COLLISION PREVEN-
TION ASSIST PLUS (
Ypage 70)
RPRE-SAFE®Brake (Ypage 75)
RBlind Spot Assist (Ypage 217) or Active
Blind Spot Assist (
Ypage 222)
RATTENTION ASSIST (Ypage 214)
RLane Keeping Assist (Ypage 220) or
Active Lane Keeping Assist
(
Ypage 225)
RRear window wiper (Ypage 135)
XPress :to display the ATTEN-
TION ASSIST assessment.
Service menu
Introduction
Depending on the equipment installed in the
vehicle, you have the following options in the
Service
menu:
RCalling up display messages in message
memory (
Ypage 257)
RChecking the tire pressure electronically
(
Ypage 383)
RCalling up the service due date
(
Ypage 343)
Settings menu
Introduction
Depending on the equipment installed in the
vehicle, you have the following options in the
Settings
menu:
RChanging assistance settings
(
Ypage 252)
RChanging head-up display settings
(
Ypage 254)
RChanging the light settings (Ypage 255)
RChanging the instrument cluster settings
(
Ypage 255)
RRestoring the factory settings
(
Ypage 256)
Assistance submenu
Activating/deactivating COLLISION PRE-
VENTION ASSIST PLUS
XPress the òbutton on the steering
wheel to open the menu list.
XPress the :or9 button on the steer-
ing wheel to select the Settings
menu.
XConfirm by pressingaon the steering
wheel.
XUse : or9 to select the DriveAs‐
sistsubmenu.
XPressato confirm.
XPress 9or: to select Collision
Prevention.
252Menus and submenus
On-board computer and displays
XPressato confirm.
The current selection appears.
XTo activate/deactivate: press thea
button again.
When COLLISION PREVENTION ASSIST
PLUS is deactivated, the æsymbol
appears in the multifunction display in the
Assistance Graphic
menu.
For further information about COLLISION
PREVENTION ASSIST PLUS, see (
Ypage 70).
Activating/deactivating PRE-SAFE
®
Brake
PRE ‑SAFE
®Brake is only available for vehi-
cles with the Driving Assistance package.
XPress the òbutton on the steering
wheel to open the menu list.
XPress the :or9 button on the steer-
ing wheel to select the Settings
menu.
XConfirm by pressingaon the steering
wheel.
XUse : or9 to select the DriveAs‐
sistsubmenu.
XPressato confirm.
XPress :or9 to select PRE-SAFE
Brake.
XPressato confirm.
The current selection appears.
XTo activate/deactivate: press thea
button again.
When PRE-SAFE
®Brake is deactivated, the
æ symbol appears in the multifunction
display in the Assistance
Graphicmenu.
For more information on PRE ‑SAFE
®Brake,
see (
Ypage 75).
Activating/deactivating Blind Spot Assist
XPress the òbutton on the steering
wheel to open the menu list.
XPress the :or9 button on the steer-
ing wheel to select the Settings
menu.
XConfirm by pressingaon the steering
wheel.
XUse : or9 to select the DriveAs‐
sistsubmenu.
XPressato confirm.
XPress :or9 to select BlindSpot
Assist.
XPressato confirm.
The current selection appears.
XTo activate/deactivate: press thea
button again.
For further information about Blind Spot
Assist, see (
Ypage 217).
For further information about Active Blind
Spot Assist, see (
Ypage 222).
Setting ATTENTION ASSIST
XPress the òbutton on the steering
wheel to open the menu list.
XPress the :or9 button on the steer-
ing wheel to select the Settings
menu.
XConfirm by pressingaon the steering
wheel.
XUse : or9 to select the DriveAs‐
sistsubmenu.
XPressato confirm.
XPress :or9 to select ATTENTION
ASSIST.
XPressato confirm.
XPress :or9 to select Off,Stand‐
ardor Sensitive.
XPress the abutton to confirm the selec-
tion.
When ATTENTION ASSIST is deactivated,
the é symbol appears in the Assis‐
tance Graphicmenu in the multifunction
display.
For further information about ATTENTION
ASSIST, see (
Ypage 214).
Setting Lane Keeping Assist
XPress the òbutton on the steering
wheel to open the menu list.
XPress the :or9 button on the steer-
ing wheel to select the Settings
menu.
Menus and submenus253
On-board computer and displays
Z
Safety systems
Display messagesPossible causes/consequences andMSolutions
!÷
Currently Unavail‐
able See Opera‐
tor's Manual
ABS (Anti-lock Brake System), ESP®(Electronic Stability Program),
BAS (Brake Assist), PRE‑ SAFE®, HOLD function, Crosswind Assist,
hill start assist, STEER CONTROL, Active Lane Keeping Assist and
Active Blind Spot Assist are temporarily unavailable.
BAS PLUS with Cross-Traffic Assist, PRE‑SAFE
®Brake, PRE‑ SAFE®
PLUS and COLLISION PREVENTION ASSIST PLUS may also have
failed.
In addition, the ÷and! warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
For example, the on-board voltage may be insufficient.
GWARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP
®is not operational, ESP®is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
XDrive on carefully.
Carefully drive a suitable distance, making slight steering move-
ments at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the multifunction display still shows the display message:
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
!÷
Inoperative See
Operator's Manual
ABS, ESP®, BAS, PRE‑SAFE®, HOLD function, Crosswind Assist,
hill start assist, STEER CONTROL, Active Lane Keeping Assist and Active Blind Spot Assist are unavailable due to a malfunction.
BAS PLUS with Cross-Traffic Assist, PRE‑ SAFE
®Brake, PRE‑SAFE®
PLUS and COLLISION PREVENTION ASSIST PLUS may also have
failed.
The$ (USA only) or J(Canada only), ÷and! warn-
ing lamps in the instrument cluster may also light up.
ATTENTION ASSIST is deactivated.
GWARNING
258Display messages
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
The brakesystem continues to function normally, but without th e
function slisted above. The wheels could therefore loc kif you
brak ehard, fo rexample.
The steerabilit yand brakin gcharacteristics may be severely affec -
ted. The brakin gdistanc ein an emergenc ybrakin gsituation can
increase .
If ES P
®is no toperational, ES P®is unable to stabiliz eth evehicle.
There is an increase dris kof skiddin gand an accident.
XDrive on carefully.
XVisit aqualified specialist workshop immediately.
÷
Inoperative See
Operator' sManual
ES P®,BAS, PRE ‑SAFE®, HOLD function ,Crosswin dAssist, hill
start assist ,STEE RCONTROL ,Active Lan eKeepin gAssis tand
Active Blind Spot Assis tare unavailable due to amalfunction .
BA SPLU Swit hCross-Traffic Assist, PRE ‑SAFE
®Brake ,PRE ‑S AF E®
PLU Sand COLLISION PREVENTION ASSIST PLU Smay also hav e
failed.
The ÷ warnin glamp also lights up in th einstrumen tcluster.
ATTENTION ASSIST is deactivated.
GWARNIN G
The brakesystem continues to function normally, but without th e
function slisted above.
The brakin gdistanc ein an emergenc ybrakin gsituation can thus
increase .
If ES P
®is no toperational, ES P®is unable to stabiliz eth evehicle.
There is an increase dris kof skiddin gand an accident.
XDrive on carefully.
XVisit aqualified specialist workshop immediately.
Display messages25 9
On-board computer and displays
Z