trailer MERCEDES-BENZ GL 2016 Owner's Guide

R
Uphill or downhill gradient in percentage R
On-road/off-road program selected R
Condition of the differential lock for the
transfer case R
LOW RANGE off-road gear is selected R
Condition of the LOW RANGE off-road
gear R
On-road trailer program is selected
Towing a trailer
Important safety notes
G WARNING
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 man-
ufacturer on the vehicle identification plates
and those for the towing vehicle under "Tech-
nical data" ( Y
page 458).
G WARNING
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.
G WARNING
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
detachable 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: R
the permissible trailer drawbar noseweight R
the permissible trailer load R
the permissible rear axle load of the towing
vehicle R
the 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: R
in the vehicle documents R
on the identification plates for the trailer
tow hitch and the trailer R
on 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: R
is heavier R
is restricted in its acceleration and gradi-
ent-climbing capability R
has an increased braking distance R
is affected more by strong crosswinds R
demands more sensitive steering R
has a larger turning radius Towing a trailer 263
Driving and parking Z

This could impair the handling characteris-
tics.
When towing a trailer, always adjust your
speed to the current road and weather con-
ditions. Do not exceed the maximum permis-
sible speed for your vehicle/trailer combina-
tion.
Notes on towing a trailer
General notes The following models cannot be used to tow a
trailer: R
GLE 550 e 4MATIC Sport Utility Vehicle R
Do not exceed the legally prescribed max-
imum speed for vehicle/trailer combina-
tions in the relevant country.
This lowers the risk of an accident. R
Only install an approved trailer coupling on
your vehicle.
Further information on availability and on
installation is available from any authorized
Mercedes-Benz Center. R
The bumpers of your vehicle are not suita-
ble for installing detachable trailer cou-
plings. R
Do not install hired trailer couplings or
other detachable trailer couplings on the
bumpers of your vehicle. R
If you no longer need the ball coupling,
remove it from the ball coupling recess.
This will reduce the risk of damage to the
ball coupling.
When towing a trailer, set the tire pressure on
the rear axle of the towing vehicle for the
maximum load. You will find the values in the
tire pressure table in the fuel filler flap of the
vehicle ( Y
page 425).
Please note that when towing a trailer, the
following driving systems have limited avail-
ability or are not available at all: R
PARKTRONIC ( Y
page 224)R
Blind Spot Assist ( Y
page 244)R
Active Lane Keeping Assist ( Y
page 251) You will find installing dimensions and loads
under "Technical data" ( Y
page 457).
Driving tips Observe the information on ESP ®
trailer sta-
bilization ( Y
page 75) and on pulling away with
a trailer ( Y
page 168).
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. See "Technical data" to
find out whether this applies to your vehicle
( Y
page 458). 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 oper-
ating permit. This also applies in countries in
which the permissible maximum speed for
vehicle/trailer combinations 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.
This also applies if you have activated cruise
control or DISTRONIC PLUS.
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.264
Towing a trailer
Driving and parking

Drivin g tipsIf th e trailer swings from sid e to side:X
Do no t accelerate.X
Do no t counter-steer .X
Brak e if necessary.R
Maintain a greater distanc e from th e vehi-
cl e in fron t than when drivin g without a
trailer .R
Avoid braking abruptly. If possible, brake
gentl y at first to allow th e trailer to run on .
Then, increase th e braking forc e rapidly.R
The values given fo r gradient-climbin g
capabilities from a standstill refer to sea
level. Whe n drivin g in mountainous areas,
note that th e powe r output of th e engin e
and , consequently, th e vehicle' s gradient-
climbin g capability, decreases wit h
increasing altitude.
Installing th e ball coupling
G WARNING
If th e ball couplin g is no t correctl y installed
and secured, it can come loose durin g th e
journey and endanger other road users. There
is a ris k of an acciden t and injury.
Always install and secure th e ball couplin g as
described . Before every journey, ensur e that
th e ball couplin g is secure d wit h th e bolt and
th e correspondin g sprin g cotter.
G WARNING
If th e ball couplin g is no t installed correctl y or
no t secure d wit h th e bolt provided and th e
correspondin g sprin g cotter, th e trailer may
come loose. There is a ris k of an accident.
Always install and secure th e ball couplin g as
described . Before every journey, ensur e that
th e ball couplin g is secure d wit h th e bolt and
th e correspondin g sprin g cotter. G WARNING
If th e ball couplin g is no t installed and secure d
correctl y th e trailer may come loose. There is
a ris k of an accident.
Install and secure th e ball couplin g as descri-
bed in th e ball couplin g installation instruc -
tions. Mak e sur e that th e ball couplin g is
installed and secure d correctl y befor e every
journey.
X
Pull protective cap C in th e direction of th e
arrow, out of th e ball couplin g recess .X
Stow protective cap C so that it canno t be
thrown around .
Observ e th e loadin g guidelines
( Y
page 340) and th e safet y note s regard -
in g stowag e spaces ( Y
page 341).Towing a trailer 265
Driving and parking Z

so will result in a loss of function of the
brake systems of both the vehicle and the
trailer. X
Shift the transmission to position P .X
Apply the vehicle's electric parking brake. X
Start the engine. X
Vehicles with the AIRMATIC package:
select highway level. X
Vehicles with ADS: set ADS to AUTO or
COMF .X
Switch off the engine. X
Close the doors and tailgate. X
Couple up the trailer. X
Establish the electrical connection
between the vehicle and the trailer. X
Check that the trailer lighting system is
working.
i Vehicles with the AIRMATIC package:
with a trailer attached, the vehicle will
always remain at highway level. When cou-
pling up a trailer, please observe the fol-
lowing: R
Unless 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. R
High-speed level 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 (width and length).
Most U.S. states and all Canadian provinces
require by law: R
Safety 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. R
A separate brake system for certain types
of trailer. R
Safety 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: R
in your place of residence R
in the location to which you are driving
The police and local authorities can provide
reliable information.
Observe the following when towing a trailer: R
To 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 R
Before driving, check: -
trailer tow hitch -
safety switch for braked trailers -
safety chains -
electrical connections -
lights -
wheels R
Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer. R
If the trailer has electronically controlled
brakes, pull away carefully. Brake manually Towing a trailer 267
Driving and parking Z

using the brake controller and check
whether the brakes function correctly. R
Se cure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion. R
When 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. R
Bear in mind that the han dlin g will be less
st able when towing a trailer than when driv-
ing wit hout one. Avoid sudden steering
movements. R
The vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient cli mbin g capability and a longer
braking dist ance.
It is more susceptible to side winds and
requires more careful steering. R
If poss ible, do not brake suddenly, but
instead depr ess the brake pedal moder-
ate ly at first so that the trailer can activate
it s brakes. Then increase the pressure on
the brake pedal. R
If the automat ic transmission repeat edly
shifts between gears on uphill or down hill
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. R
When driv ing down hill, shift to a lower gear
to uti liz e the engine's braking effect.
Avoid continuous brake application as this
m ay
overheat the vehicle brakes and, if
instal led, the trailer brakes.R
If the coolant temperature increases dra-
matical ly while the air-cond it ioning system
is swit ched on, switch off the air-condition-
ing system.
Coolant heat can also be dissipated by
opening the win dows and switching the ventilation blowe r and the interior temper-
ature to the highest leve l.R
When overtaking, pay particular attention
to the extended length of your vehicle/
trailer combination.
Due to the length of the vehicle/trailer
combination, 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
G WARNIN G
If you uncouple a trailer wit h th e overrun
brak e engaged , you could trap your han d
between th e vehicl e and th e trailer drawbar.
Ther e is a ris k of injury.
Do no t uncouple a trailer if th e overrun brak e
is engaged .
G WARNIN G
Vehicles wit h leve l control :
The vehicl e is lowered as soo n as you discon -
nect th e trailer cable. This could result in your
limb s or those of other people that are
between th e vehicl e body and tires or under-
neath th e vehicl e bein g trapped . Ther e is a
ris k of injury.
Mak e sure that nobody is in th e immediat e
vicinity of th e whee l housing s or under th e
vehicl e when you disconnect th e trailer cable.
! Do not disc onnect a trailer wit h an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the reboun d-
ing of the overrun brake. X
Sh ift the transmission to position P .X
Ap ply the vehicle's electr ic parking brake.X
St art the engine. X
Close the doors and tailgate. X
Apply the trailer's parking brake.268
Towing a trailer
Driving and parking

X
Detach the trailer cable and decouple the
trailer. X
Switch off the engine.
Permissible trailer loads and drawbar
loads
Weight specifications Maximum permissible gross vehicle
weight rating
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" ( Y
page 457).
Permissible noseweight
You will find installing dimensions and loads
under "Technical data" ( Y
page 457).
Loading a trailer R
When 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. R
The 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.
i Mercedes-Benz recommends a trailer
load where the trailer drawbar noseweight accounts for 8% to 15% of the trailer's per-
missible gross weight.
i The weight of additional accessories, pas-
sengers, and cargo reduces the permissi-
ble trailer load and drawbar load for your
vehicle.
Checking the vehicle and trailer weight R
To check that the weights of the towing
vehicle and the trailer comply with the max-
imum permissible values, have the vehicle/
trailer combination (including the driver,
passengers, and cargo with a fully laden
trailer) weighed on a calibrated weigh-
bridge. R
Check the gross axle weight rating of the
front and rear axles, the gross weight of the
trailer and trailer drawbar load.
Removing the ball coupling X
Remove the spring cotter. X
Remove the bolt from the ball coupling
recess. X
Remove the ball coupling from the ball cou-
pling recess. X
Clean the ball coupling if it is dirty. X
Stow the ball coupling so that it cannot be
thrown around.
Observe the loading guidelines ( Y
page 340)
and the safety notes regarding stowage
spaces ( Y
page 341).
Information on cleaning and care of the trailer
tow hitch ( Y
page 381).
Trailer power supply
! You can connect accessories with a max-
imum power consumption of 240 W 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. Towing a trailer 269
Driving an d parking Z

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.270
Towing a trailer
Driving and parking

Display messages
Possible causes/consequences and P Solutions
If these condition s are fulfilled , th e front-passenger seat can be
occupied again . Whether th e PASSENGER AI R BA G OF F indicato r
lamp remain s lit or goe s out depend s on how OCS classifie s th e
occupant .
If th e condition s are no t fulfilled , th e system is no t operating cor-
rectly. X
Visit a qualified specialist workshop immediately.
Lights
i Vehicles wit h LE D bulbs in th e ligh t clusters :
The display message fo r th e correspondin g lamp only appears when all of th e LEDs in th e
lamp hav e failed.
Display messages
Possible causes/consequences and P Solutions
I Check Lef t Corner ‐
ing Light or Check
Right Cornering
Light The lef t or right-hand cornering ligh t is defective.X
Visit a qualified specialist workshop .
I Check Lef t Low
Bea m or Check
Right Low Bea m The lef t or right-hand low-beam headlamp is defective. X
Chec k whether you are permitte d to replac e th e bulb yourself
( Y
page 136).
or X
Visit a qualified specialist workshop .
I Traile r right tai l
lam p The lef t or right-hand trailer tai l lamp is faulty.X
Consult th e manufacturer' s operating instructions.
I Traile r lef t indi‐
cator or Traile r
right indicator The lef t or right-hand trailer tur n signal lamp is defective.X
Consult th e manufacturer' s operating instructions.
I Traile r brake lam p The trailer brak e lamp is defective.X
Consult th e manufacturer' s operating instructions.Display messages 30 3
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
I Front lef t parkin g
lam p or Front
right parkin g lam p The fron t lef t or fron t right parkin g or standin g lamp is defective.X
Chec k whether you are permitte d to replac e th e bulb yourself
( Y
page 137).
or X
Visit a qualified specialist workshop .
I Backup Light The backup lamp is defective. X
Visit a qualified specialist workshop .
I Front lef t sid e
marker lam p or
Front right sid e
marker lam p The fron t left-han d or fron t right-hand side marke r lamp is faulty.X
Visit a qualified specialist workshop .
I Lef t tai l lam p or
Right tai l lam p The lef t or right-hand tai l lamp is defective.
or
The rear left-han d or rear right-hand side marke r lamp is faulty.X
Visit a qualified specialist workshop .
I Check Lef t Daytim e
Runnin g Light or
Check Right Day ‐
tim e Runnin g Light The lef t or right-hand daytime running lamp is faulty. X
Visit a qualified specialist workshop .
I Active Light Sys ‐
tem inoperative The active ligh t function is faulty. X
Visit a qualified specialist workshop .
I Malfunction See
Operator' s Manual The exterio r lighting is defective. X
Visit a qualified specialist workshop .
Vehicles wit h trailer to w hitch : a fus e may hav e blown .X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions.X
Secur e th e vehicl e against rollin g away ( Y
page 189).X
Chec k th e fuses ( Y
page 400).X
If necessary, replac e th e blown fuse. Observ e th e warnin g notes.
If th e display message continues to be displayed: X
Visit a qualified specialist workshop .Display messages 30 5
On-board computer and displays Z

Display messages
Possible causes/consequences and P Solutions
Blind Spo t Assist
Not Available Whe n
Towing a Traile r
See Operator' s Man ‐
ual or A ct. Blind
Spo t Asst. Not
Available Whe n Tow ‐
ing a Traile r See
Operator' s Manual Blind Spot Assis t or Active Blind Spot Assis t is deactivated while
towin g a trailer .
You hav e established th e electrica l connection between th e trailer
and your vehicle. X
Press v on th e steerin g whee l to confirm th e display mes -
sage .
Blind Spo t Assist
inopera‐
tiv e or Active Blind
Spo t Assist inoper ‐
ative Blind Spot Assis t or Active Blind Spot Assis t is defective.
The yello w c indicato r lamp s also ligh t up in th e exterio r mir -
rors. X
Visit a qualified specialist workshop .
Par k Assist Can ‐
celed The driver's doo r is open .X
Repea t th e parkin g gap measuremen t and parkin g process wit h
th e driver's doo r closed .
You hav e inadvertentl y touched th e multifunction steerin g whee l
while steerin g intervention was active .X
Whil e steerin g intervention is active , mak e sur e that th e multi-
function steerin g whee l is no t touched unintentionally.
The vehicl e has started to skid and ES P ®
has intervened.X
Use Active Parking Assis t again later ( Y
page 227).
Par k Assist Inoper ‐
ative PARKTRONI C is malfunctionin g or faulty.X
Follow th e instruction s and helpful hints in th e "Problems wit h
PARKTRONIC" section ( Y
page 227).
If th e multifunction display still shows th e display message :X
Visit a qualified specialist workshop .
Active Parking Assis t is unavailable or faulty.X
Switc h of f th e ignition and restar t th e engine.
If Active Parking Assis t continues to be unavailable (the ] symbol
does no t appea r in th e multifunction display):X
Visit a qualified specialist workshop .
Par k Assist
switched off The vehicl e is parked. A warnin g tone also sounds.
The display message disappear s automatically.Display messages 31 5
On-board computer and displays Z