trailer MERCEDES-BENZ GL 2010 Owner's Manual

Tread
The portion of a tire that comes into contact
with the road.
Treadwear indicators
Narrow bands, sometimes called “wear bars”
that show across the tread of a tire when only
1 / 16 in (1.6 mm) of tread remains.
TWR (Tongue Weight Rating)
Maximum permissible weight on trailer
tongue.
Uniform Tire Quality Grading Standards
A tire information system that provides
consumers with ratings for a tire’s traction,
temperature and treadwear. Ratings are
determined by tire manufacturers using U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
Vehicle maximum load on the tire
Load on an individual tire that is determined
by distributing to each axle its share of the
maximum loaded vehicle weight and dividing
it by two.
Winter driving
General information
Have your vehicle winterized at an authorized
Mercedes-Benz Center.
i Vehicles with diesel engine:
Do not cover the radiator, for example with
a winter front. Otherwise the readings of
the on-board diagnostic system may be
inaccurate. Some of theses readings are
required by law and must be accurate at all
times.
Winter tiresGWarning!
Winter tires with a tread depth of less than
1 / 6 in (4 mm) must be replaced. They are no
longer suitable for winter operation.
GWarning!
If you use your spare wheel when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may very
well impair turning stability and that overall
driving stability may be reduced. Adapt your
driving style accordingly.
Have the spare wheel replaced by a regular
road wheel with a winter tire at the nearest
authorized Mercedes-Benz Center.
Always use winter tires at temperatures
below 45‡ (7†) and whenever wintry road
conditions prevail. Not all M+S rated tires
provide special winter performance. Make
sure the tires you use show the mountain/
snowflake imarking on the tire sidewall.
These tires meet specific snow traction
performance requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC) and
have been designed specifically for use in
snow conditions. Use of winter tires is the
only way to achieve the maximum
effectiveness of your vehicle’s driving safety
systems such as the ABS and the ESP ®
in
winter operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
For information on winter tires for your
vehicle model, see the “Technical data”
section ( Y page 365).
Always observe the speed rating of the winter
tires installed on your vehicle.
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Trailer towingGWarning!
Failure to use proper equipment and driving
technique can result in a loss of vehicle
control when towing a trailer.
Improper towing or failure to follow the
instructions in this manual can result in
vehicle damage and/or serious personal
injury. Follow the guidelines below carefully
to assure safe trailer operation.
Contact an authorized Mercedes-Benz Center
should you require an explanation of
information contained in this manual.
Trailer hitch
R Only install a trailer hitch receiver approved
for your vehicle.
For information on availability and
installation, contact an authorized
Mercedes-Benz Center.
R The bumpers on your vehicle are not
designed for use with clamp-type hitches.
Do not attach rental hitches or other
bumper-type hitches to them.
R To reduce the possibility of damage,
remove the hitch ball adapter from the
receiver when not in use.
Electrical connections
The vehicle is prewired to accept the seven-
wire harness included in the Mercedes-Benz
approved trailer hitch receiver kit.
i A four-pole conversion plug is available
from your authorized Mercedes-Benz
Center as a spare part.
For further information, contact an
authorized Mercedes-Benz Center.
Vehicle and trailer weights and ratings
The Gross Trailer Weight (GTW) is the weight
of the trailer plus the weight of all cargo,
equipment, luggage, etc. loaded on the
trailer. The maximum permissible GTW to be
towed: 7 500 lb (3 402 kg).
Trailer Tongue Weight Rating (TWR) is the
maximum permissible weight on the trailer
tongue: 600 lb (272 kg) limit for Mercedes-
Benz approved hitch receiver.
Loading a trailer
R When loading a trailer, you should observe
that neither the permissible GTW, nor the
Gross Vehicle Weight Rating (GVWR) are
exceeded. The GVWR is indicated on the
certification label located on the driver’s
door B-pillar ( Y page 242).
Maximum permissible values are listed on
the safety compliance certification labels
for the vehicle and for the trailer to be
towed.
The lowest value listed must be selected
when determining how the vehicle and
trailer are loaded.
R The tongue weight at the hitch ball must be
added to the rear axle weight to prevent
exceeding the rear Gross Axle Weight
Rating (GAWR). The GAWR is indicated on
the certification label located on the
driver’s door B-pillar ( Y page 242).
i Mercedes-Benz recommends loading the
trailer in such a manner that it has a tongue
weight between 8 % and 15 % of the GTW.
i The weight of other accessories,
passengers and cargo will reduce the
maximum trailer weight and tongue weight
your vehicle can tow.
Checking weights of vehicle and trailer
R To assure that the towing vehicle and trailer
are in compliance with the maximum
permissible weight limits, have the loaded
rig (towing vehicle including driver,
passengers and cargo, trailer fully loaded)
weighed on a commercial scale.
R Check the vehicle’s front and rear gross
axle weight, the Gross Trailer Weight (GTW)
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The values as measured must not exceed
the weight limits listed under “Vehicle and
trailer weights and ratings” ( Y page 269).
Coupling a trailer GWarning!
While you are coupling or decoupling a trailer,
make sure nobody locks or unlocks the
vehicle and/or opens or closes doors or the
tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result.
Make sure that you do not operate the ADS
button or the vehicle level control system
when coupling/decoupling the trailer.
Observe maximum permitted trailer
dimensions (width and length).
Most states and all Canadian provinces
require
R safety chains between the towing vehicle
and the trailer
The chains should be criss-crossed under
the trailer tongue. They must be attached
to the hitch receiver, and not to the
vehicle’s bumper or axle.
Make sure to leave enough slack in the
chains to permit turning corners.
R a separate brake system at various trailer
weights
R a break-away switch on trailers with a
separate brake system.
Check with your local state laws for specific
requirements.
The switch activates the trailer brakes in
the possible event that the trailer might
separate from the tow vehicle.
! Do not connect a trailer brake system (if
trailer is so equipped) directly to the
vehicle’s hydraulic brake system, as your
vehicle is equipped with antilock brakes. If
you do, neither the vehicle’s brakes nor the
trailer’s brakes will function properly.
i The provided vehicle electrical wiring
harness for trailer towing has a brake signal
wire for hook-up to a brake controller.XMake sure the automatic transmission is in
park position P (Y page 115).XEngage the parking brake for the vehicle
( Y page 112).XStart the engine ( Y page 108).XSelect the highway level ( Y page 159).XVehicles with Adaptive Damping System
(ADS):
Set the ADS to AUTO or COMF
( Y page 159).XTurn off the engine ( Y page 113).XClose all doors and the tailgate.XAttach the trailer.XPlug in all electrical connectors.
i
When you are towing a trailer, the vehicle
level always remains in the highway setting.
The following applies additionally when
towing a trailer:
R The vehicle is lowered to the highway
level when it reaches a speed of 5 mph
(8 km/h) if not set to highway level.
R The highspeed level is not available.
The restrictions that apply to towing also
apply when using accessories that are
connected to the trailer power socket, such
as a bicycle rack.
Towing a trailer
There are many different laws, including
speed limit restrictions, having to do with
trailer towing. Make sure your rig will be legal,
not only for where you reside, but also for
where you will be driving. A good source for
this information can be the police or local
authorities.
Note the following, when driving with a trailer:
R In order to gain skill and an understanding
of the vehicle’s behavior, you should
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practice turning, stopping and backing up
in an area which is free of traffic.
R Before you start driving check the
- trailer hitch
- break-away switch
- safety chains
- electrical connections
- lighting
- tires
R Adjust the mirrors ( Y page 94) to permit
unobstructed view beyond rear of trailer.
R If the trailer has electric brakes, start your
vehicle and trailer moving slowly, and then
apply only the trailer brake controller by
hand to make sure the brakes are working
properly.
R Always secure items in the trailer to
prevent load shifts while driving.
R When towing a trailer, check occasionally
to make sure the load is secure, and that
trailer lighting and brakes (if so equipped)
are functioning properly.
R Take into consideration that when towing a
trailer, the handling characteristics are
different and less stable from those when
operating the vehicle without a trailer.
It is important to avoid sudden maneuvers.
R The vehicle and trailer combination is
heavier, and therefore limited in
acceleration and climbing ability, and has a
larger braking distance.
It is more prone to reacting to cross wind
gusts, and requires more sensitive steering
input.
R If possible, do not brake abruptly, but
rather engage the brake slightly at first to
permit the trailer to activate its brake. Then
increase the braking force.
! If the trailer should begin to sway, reduce
the vehicle’s speed immediately.Do not attempt to straighten out the tow
vehicle and trailer by increasing the speed.
R If the transmission shifts between gears on
inclines repeatedly, shift to a lower gear
range manually ( Y page 118). Select 4, 3 ,
2 or 1.
A lower gear and reduction of speed
reduces the chance of engine overloading
and/or overheating.
R On very steep inclines, not manageable
with automatic transmission in gear range
1 , switch on off-road driving program
( Y page 158) or LOW RANGE mode
( Y page 120).
R When going down an incline, shift into a
lower gear and use the engine’s braking
effect.
Avoid riding the brakes, thus overheating
the vehicle and trailer brakes (if so
equipped).
R If the engine coolant rises to an extremely
high temperature when the air conditioning
is on, turn off the air conditioning system.
Engine coolant heat can be additionally
vented by opening the windows, switching
the climate control fan speed to high and
setting the temperature control to the
maximum.
R During a passing maneuver extreme care
must be exercised since your vehicle with
a trailer will require additional passing
distance ahead than when driving without
a trailer.
Because your vehicle and trailer is longer
than your vehicle alone, you will also need
to go much farther ahead of the passed
vehicle before you can return to your lane.
Decoupling a trailer GWarning!
While you are coupling or decoupling a trailer,
make sure nobody locks or unlocks the
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vehicle and/or opens or closes doors or the
tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result.
Make sure that you do not operate the ADS
button or the vehicle level control system
when coupling/decoupling the trailer.XMake sure the automatic transmission is in
park position P (Y page 115).XEngage the parking brake for the vehicle
( Y page 112).XStart the engine ( Y page 108).XClose all doors and the tailgate.XEngage the parking brake for the trailer.GWarning!
As soon as you disconnect the electrical
connection between the trailer and the
vehicle, the vehicle will lower. To help avoid
personal injury, make sure no one is near the
wheel housing or underneath the vehicle
before the electrical connection is
disconnected.
When you decouple the trailer, the vehicle is
temporarily raised because the springs are
relieved of load. Be especially careful during
this process, as you could otherwise injure
yourself and/or others. Make sure that any
persons remaining in the vehicle do not press
the switches for vehicle level control or the
ADS.
XDisconnect all electrical plug connectors.XDecouple the trailer.XMake sure that the trailer coupling is free
of load.XTurn off the engine ( Y page 113).
Driving abroad
If you plan to drive the vehicle outside the U.S.
or Canada, you should request dealer
network information for your destination from
any authorized Mercedes-Benz Center.
Control and operation of radio
transmitter
Safety notes
GWarning!
Please do not forget that your primary
responsibility is to drive the vehicle. A driver’s
attention to the road must always be his/her
primary focus when driving. For your safety
and the safety of others, we recommend that
you pull over to a safe location and stop
before placing or taking a telephone call.
If you choose to use the telephone 18
while
driving, please use the hands-free device and
only use the telephone when road, weather
and traffic conditions permit. Some
jurisdictions prohibit the driver from using a
mobile telephone while driving a vehicle.
Only operate the COMAND 18
(Cockpit
Management and Data System) if road,
weather and traffic conditions permit.
Otherwise, you may not be able to observe
traffic conditions and could endanger yourself
and others.
Bear in mind that at a speed of just 30 mph
(approximately 50 km/h), your vehicle is
covering a distance of 44 feet (approximately
14 m) every second.
Emission control
Certain systems of the engine serve to keep
the toxic components of the exhaust gases
within permissible limits required by law.
These systems will function properly only
when maintained strictly according to factory
specifications. Any adjustments on the
engine should, therefore, be carried out only
by qualified Mercedes-Benz Center
authorized technicians.
18 Observe all legal requirements.272Driving instructionsOperation
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Safety systemsDisplay messagesPossible causes/consequences and M SolutionsGTele Aid
Inoperativ
eOne or more main functions of the Tele Aid system are
malfunctioning.XHave the Tele Aid system checked at an authorized
Mercedes-Benz Center.+Restraint
Sys.
Malfunctio
n
Service
RequiredThe system is malfunctioning.XDrive with added caution to the nearest authorized
Mercedes-Benz Center and have the system checked
immediately.GWarning!
In the event a malfunction of the SRS is
indicated as outlined above, the SRS may not
be operational.
For your safety, we strongly recommend that
you contact an authorized Mercedes-Benz
Center immediately to have the system
checked. Otherwise the SRS may not be
activated when needed in an accident, which
could result in serious or fatal injury, or it
might deploy unexpectedly and unnecessarily
which could also result in injury.
Driving systems
Display messagesPossible causes/consequences and M SolutionsÁLevel
Selection
Not
PermittedThe selected vehicle level cannot be adjusted, because
R you are driving too fast for the desired vehicle level
R you are towing a trailer
R you are using accessories that are connected to the trailer
power socket, e.g. a bicycle rackXReduce vehicle speed and set the desired vehicle level
again ( Y page 159).XObserve the notes on trailer towing ( Y page 269).ÁMalfunctio
nThe air suspension is malfunctioning.XDo not drive faster than 50 mph (80 km/h).XHave the system checked at an authorized Mercedes-Benz
Center.Vehicle status messages in the multifunction display301Practical hintsX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 301Z

Display messagesPossible causes/consequences and M SolutionsbLow Beam
Left
or
Low Beam
RightThe left or right low-beam lamp is malfunctioning.XHalogen headlamp: Replace the bulb as soon as possible
( Y page 328).XBi-Xenon headlamp: Contact an authorized Mercedes-
Benz Center as soon as possible.bFoglamp
Rear LeftThe rear fog lamp is malfunctioning.XReplace the bulb as soon as possible ( Y page 328).bSwitch
Off LightsYou have removed the SmartKey from the starter switch,
opened the driver’s door and left the headlamps on or
removed the SmartKey with KEYLESS-GO from the vehicle
and left the headlamps on.XTurn the exterior lamp switch to $ or Ã
( Y page 97).
or
XWith the rear fog lamp switched on: Push in the exterior
lamp switch to its stop.bTail Lamp
Left
or
Tail Lamp
RightThe left or right tail lamp is malfunctioning. A substitute bulb
is being used.XReplace the bulb as soon as possible ( Y page 328).bTrailer
Brake LampThe left or right trailer brake lamp is malfunctioning.XReplace the bulb as soon as possible.bTrailer
Tail Lamp
Left
or
Trailer
Tail Lamp
RightThe left or right trailer tail lamp is malfunctioning.XReplace the bulb as soon as possible.bTrailer
Turn
Signal
Left
or
Trailer
Turn
Signal
RightThe left or right trailer turn signal lamp is malfunctioning.XReplace the bulb as soon as possible.312Vehicle status messages in the multifunction displayPractical hints
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XMake sure the ignition is switched on.XWith the vehicle at a standstill, depress the
brake pedal and keep it pressed.XShift the automatic transmission into
neutral position N.XRelease the brake pedal.XIf engaged, release the parking brake.XSwitch on the hazard warning flasher
( Y page 101).
!
Keep in mind that it is important to have
the ignition switched on. Removing the
SmartKey from the starter switch or
opening a front door with the ignition
switched off will automatically shift the
automatic transmission into park position
P .
! The vehicle may be towed only for
distances up to 30 miles (50 km) and at a
speed not to exceed 30 mph (50 km/h).
i While being towed with the hazard
warning flasher in use, use the combination
switch in the usual manner to signal turns.
Only the selected turn signal will operate.
Upon canceling the turn signal, the hazard
warning flasher will operate again.
Stranded vehicle
Freeing a stranded vehicle, on which the
wheels are dug into sand or mud, should be
done with the greatest of care, especially if
the vehicle is heavily loaded.
Note the following when freeing a stranded
vehicle:
R Avoid pulling the vehicle abruptly or
diagonally, since it could result in damage
to the chassis alignment.
R Never try to free a vehicle that is still
coupled to a trailer.
R If possible, a vehicle equipped with a trailer
hitch receiver should be pulled backward in
its own previously made tracks.
Fuses
Introduction
The electrical fuses in your vehicle serve to
switch off malfunctioning power circuits.
If a fuse is blown, the components and
systems secured by that fuse will stop
operating.
GWarning!
Only use fuses approved by Mercedes-Benz
with the specified amperage for the system in
question and do not attempt to repair or
bridge a blown fuse. Using other than
approved fuses or using repaired or bridged
fuses may cause an overload leading to a fire,
and/or cause damage to electrical
components and/or systems. Have the cause
determined and remedied by an authorized
Mercedes-Benz Center.
A blown fuse must be replaced by an
appropriate spare fuse (recognizable by its
color or the fuse rating given on the fuse) of
the amperage recommended in the fuse
chart. Any Mercedes-Benz Center will be glad
to advise you on this subject.
i In case of a blown fuse contact Roadside
Assistance or an authorized Mercedes-
Benz Center.
If a newly inserted fuse blows again, have the
cause determined and rectified by an
authorized Mercedes-Benz Center.
The fuse chart is located in the cargo
compartment with the vehicle tool kit
( Y page 284). The fuse chart explains the fuse
allocation and fuse amperages.
Before replacing fuses
XEngage the parking brake.XMake sure the automatic transmission is in
park position P.
The transmission position indicator in the
multifunction display should be on P.XSwitch off all electrical consumers.Fuses355Practical hintsX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 355Z