XEstablish the electrical connection between
the vehicle and the trailer.
XCheck that the trailer lighting system is work-
ing.
XPush the combination switch upwards/down-wards and check whether the corresponding
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 work-
ing properly. The function of other systems also
depends on this, for example:
RESP®
RParking Assist PARKTRONIC
RParking Pilot
RActive Blind Spot Assist
RActive Lane Keeping Assist
iVehicles with the AIRMATIC package: if you
couple up a trailer, the vehicle always remains
at normal level. When coupling up a trailer,
please observe the following:
RIf the normal level has not been set man-
ually, the vehicle is automatically lowered
to normal level. This is the case if a speed of
5 mph (8 km/h) is reached.
RThe Sport drive program is not available.
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 (wi
dth 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 fas-
tened to the vehicle's trailer coupling, 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 tow-
ing 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 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.
Towing a trailer203
Driving an d parking
Z
RIf possible, do not brake suddenly, but insteaddepress 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-
neath the vehicle being trapped. There is a
risk of injury.
Make sure that nobody is in the immediate
vicinity of the wheel housings or under the
vehicle when you disconnect the trailer cable.
!Do not disconnect a trailer with an engaged
overrun brake. Otherwise, your vehicle could
be damaged by the rebounding of the overrun brake.
XShift the transmission to position P.
XApply the vehicle's electric parking brake.
XStart the engine.
XClose the doors and tailgate.
XApply the trailer's parking brake.
XDetach the trailer cable and decouple the
trailer.
XSwitch off the engine.
Permissible trailer loads and drawbar
loads
Weight specifications
Maximum allowable gross mass
The gross vehicle weight of the trailer is calcu-
lated by adding 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 361).
Permissible noseweight
You will find installing dimensions and loads
under "Technical data" (Ypage 361).
Loading a trailer
RWhen loading the trailer, make sure that nei-
ther the permissible gross weight of the trailer
nor the gross vehicle weight are exceeded.
The permissible gross vehicle weight is indi-
cated on the identification plate located on
the B-pillar on the driver's side of the vehicle.
You can find the maximum permissible values
on the type plates of your vehicle and the
trailer. When calculating how much weight
204Towing a trailer
Driving and parking
the vehicle and trailer may carry, pay atten-
tion to the respective lowest values.
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 indi-
cated on the identification plate located 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 additional accessories, pas-
sengers, and cargo reduces the permissible
trailer load and drawbar load for your vehicle.
Checking the vehicle and trailer weight
RTo check that the weights of the towing vehi-
cle and the trailer comply with the maximum
permissible values, have the vehicle/trailer
combination (including the driver, passen-
gers, and cargo with a fully laden trailer)
weighed on a calibrated weighbridge.
RCheck the gross axle weight rating of the front and rear axles, the gross weight of the trailer
and the trailer drawbar noseweight.
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 270)
and the safety notes regarding stowage spaces
(
Ypage 270).
Information on cleaning and care of the trailer
tow hitch (
Ypage 304).
Trailer power supply
!
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 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.
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.
Towing a trailer205
Driving an d parking
Z
Change of direction announced without a
lane recommendation
:Road into which the change of direction
leads
;Distance to change of direction and visual
distance display
=Change-of-direction symbol
When a change of direction is to be made, you
will see symbol =for the change of direction
and distance graphic ;. The distance indicator
shortens towards the top of the display as you
approach the point of the announced change of
direction. The change of direction starts once
the distance display reaches zero.
Change of direction announced with a
lane recommendation
:Road into which the change of direction
leads
;Distance to change of direction and visual
distance display
=Lanes not recommended
?Recommended lane and new lane during a
change of direction
AChange-of-direction symbol
On multilane roads, lane recommendations can
be displayed for the next change of direction if
the digital map supports this data. During the
change of direction, new lanes may be added.
Lane not recommended =: you will not be able
to complete the next change of direction if you
stay in this lane.
Recommended lane and new lane during a
change of direction ?: in this lane you will be
able to complete the next two changes of direc-
tion without changing lane.
Other status indicators of the naviga-
tion system
The navigation system displays additional infor-
mation and the vehicle status.
Possible displays:
RNew Route...or Calculating Route...
A new route is calculated.
RRoad Not Mapped
The vehicle position is inside the area of the
digital map but the road is not recognized, e.g.
newly built streets, car parks or private land.
RNo Route
No route could be calculated to the selected
destination.
RO
You have reached the destination or an inter-
mediate destination.
Audio menu
Selecting a radio station
:Active station list
;Station frequency with memory position
The multifunction display shows station ;with
station frequency or station name. The preset
position is only displayed along with station ;if
this has been stored. You can store TV chan-
nels ;in the multimedia system.
XSwitch on the multimedia system and select
radio; see the separate operating instruc-
tions.
XPress the =or; button on the steering
wheel to select the Audiomenu.
Menus and submenus211
On-board computer and displays
Z
Display messagesPossible causes/consequences andMSolutions
The yellow!warning lamp and th ered F (USAonly) or !
(Canada only) indicator lamp ligh tup.
The electric parking brak eis malfunctioning .
To release:
XSwitc hoff th eignition and tur nit bac kon .
XReleas eth eelectric parking brak emanually.
or
XReleas eth eelectric parking brak eautomatically (Ypage 146).
If th eelectric parking brak estill canno tbe released:
XDo no tdrive on .
XConsult aqualified specialist workshop .
The redF(USAonly) or !(Canada only) indicator lamp flashes
and th eyellow !warning lamp lights up.
The electric parking brak eis malfunctioning .
To release:
XSwitc hoff th eignition and tur nit bac kon .
XReleas eth eelectric parking brak emanually.
To apply :
XSwitchoff th eignition and tur nit bac kon .
XApply th eelectric parking brak emanually.
If th ered F (USAonly) or !(Canada only) indicator lamp con-
tinue sto flash:
XDo no tdrive on .
XSecureth evehicl eagainst rollin gaway (Ypage 342).
XShift th etransmission to position P.
XTurn thefron twheels toward sth ecurb.
XConsult aqualified specialist workshop .
Display messages225
On-board computer and displays
Z
Drivingsystems
Display messagesPossible causes/consequences an dMSolutions
À
Attention Assist :Take a Break!
Based on certain criteria, ATTENTION ASSIST has detecte dfatigue or
a lac kof concentration on th epar tof th edriver . Awarnin gtone also
sounds.
XIf necessary, take abreak .
Durin glon gjourneys, take regular break sin goo dtime so you get
enough rest.
À
Attention AssistInoperative
ATTENTION ASSIST is inoperative .
XVisitaqualified specialis tworkshop .
Á
Drive Mor eSlowly
You canno tchang eth evehicle level.
Possible causes are :
Ryou are drivingto ofas tfo rth eselecte dvehicle level
Ryou are drivin gto ofas twit h a trailer or th etrailer-couplin gsocke tis
bein gused ,e.g. fo r abicycl erac k
XDrive more slowly and then selec tth edesire dvehicle level again
(Ypage 171).
XObserv eth enote son towin g atrailer (Ypage 200).
Á
Compresso rIs Cool‐ing
You hav eselecte d ahigher vehicle level. The compressor first needs
to cool down because of frequent level changes.
XDrive in amanne rappropriat efo rth ecurren tvehicle level.
XMak esur ethat there is sufficien tgroun dclearance.
XAllow th ecompressor to cool down .
Whe nth ecompressor has cooled down ,th edisplay messag edis -
appears .The vehicle then continues risin gto th eselecte dlevel.
Á
Malfunction
AIRMATIC is malfunctioning.
XDrive as appropriat efo rth ecurren tvehicle level, but do no texceed
50 mph (80 km/h).
XMak esur ethat there is sufficien tgroun dclearance.
XVisit aqualified specialis tworkshop .
ACTIVECURVESYSTEMMalfunctionThe ACTIV ECURV ESYSTEM is malfunctioning. The vehicle' shandlin g
characteristics may be affected.
XDo no tdrive at speeds abov e50 mph (80 km/h).
XVisit aqualified specialis tworkshop .
238Display messages
On-board computer and displays
Display messagesPossible causes/consequences andMSolutions
LaneKeepin gAssistCurrently Unavaila‐ble See Operator' sManualorActive Lan eKeepingAssist Cur ‐rently UnavailableSee Operator' sMan ‐ual
LaneKeepin gAssis tor Active Lan eKeepin gAssis tis deactivated and
temporarily inoperative.
Possibl ecauses are:
Rth ewindshield in th ecamera' sfield of vision is dirty
Rvisibilit yis impaire ddue to heav yrain ,snow or fog
Rthere hav ebeen no lan emarking sfor an extended period
Rth elan emarking sare worn, dark or covered, e.g. by dir tor snow
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Lan eKeepin gAssis tor Active Lan eKeepin gAssis tis operational
again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 145).
XClean th ewindshield.
Lan eKeepin gAssistInoperativeorActiveLan eKeepin gAssistInoperative
LaneKeepin gAssis tor Active Lan eKeepin gAssis tis malfunctioning .
XVisitaqualified specialist workshop .
Blind SpotAssistCurrently Unavaila‐ble See Operator' sManualorActiveBlind Spo tAssistCurrently Unavaila‐ble See Operator' sManual
Blind Spot Assistor Active Blind Spot Assis tis temporarily inoperative.
Possibl ecauses are:
Rth eradar sensor system is outside th eoperating temperature range
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation
The yellow 9indicator lamp salso ligh tup in th eexterio rmirrors.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Blind Spot Assis tor Active Blind Spot Assis tis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 145).
XRestart th eengine.
Blind Spo tAssistNot Available Whe nTowingaTraile rSee Operator' sMan ‐ualorAct. BlindSpo tAsst. NotAvailable Whe nTow ‐ing aTraile rSeeOperator' sManual
Blind Spot Assis tor Active Blind Spot Assis tis deactivated while tow-
ing atrailer .
You hav eestablished th eelectrical connection between th etrailer and
your vehicle.
XPress aon thesteering whee lto confirm th edisplay message .
240Display messages
On-board computer and displays
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
üNThe red seat belt warning lamp lights up after the engine starts, as soon as the
driver's or the front-passenger door is closed.
The driver or front passenger has not fastened their seat belt.
XFasten your seat belt (Ypage 42).
The warning lamp goes out.
There are objects on the front-passenger seat.
XRemove the objects from the front-passenger seat and stow them in a secure
place.
The warning lamp goes out.
üN The red seat belt warning lamp flashes and an intermittent audible warning
sounds.
The driver or front passenger has not fastened their seat belt. The vehicle is being driven faster than 15 mph (25 km/h) or has briefly been driven faster than 15 mph
(25 km/h).
XFasten your seat belt (Ypage 42).
The warning lamp goes out and the intermittent warning tone ceases.
There are objects on the front-passenger seat. The vehicle is being driven faster
than 15 mph (25 km/h) or has briefly been driven faster than 15 mph (25 km/h).
XRemove the objects from the front-passenger seat and stow them in a secure
place.
The warning lamp goes out and the intermittent warning tone ceases.
Warning and indicator lamps in the instrument cluster251
On-board computer and displays
Z