2012 MERCEDES-BENZ GL transmission

process has not been completed. LOW
RANGE is in the neutral position. There is no
connection between the engine and the drive
wheels.
! Do not drive any further, otherwise you
could damage the vehicle’s drive train.XStop the vehicle. Take into account the
road and traffic conditions when doing this.XDepress the parking brake.XCarry out the gear change process again.
If the gear change process has been carried
out, the Stop vehicle Apply parking
brake message disappears.
Differential lock
General notes
i Differential locks are available only in
vehicles with the Off-Road Pro engineering
package.
Your vehicle is equipped with the following:
R A differential lock for the transfer box: this
controls the balance between the front and
rear axles.
R A differential lock for the rear axle: this
controls the balance between the wheels
and the rear axle.
Differential locks improve the vehicle's
traction. 4ETS ( Y page 70) controls the
balance between the wheels on the front axle.
For information about driving off-road, see
( Y page 174).
Information on differential and
differential locks
When the vehicle drives around a corner, the
wheels on the outside of the bend must cover
a greater distance and must therefore turn
more rapidly than the wheels on the inside.
The differential, a transmission in the drive
train, compensates for these different
rotational speeds, making cornering possible.
A differential has the disadvantage that the
wheels with the least road grip are driven with
the greatest force. An example: a wheel of a
driven axle is on a snow-covered surface and
therefore does not have any traction. The
differential causes this wheel to be subjected
to the strongest driving force, as the flow of
force takes the path of least resistance. On
the other hand, the opposite wheel on this
axle, which is located on a firm surface and
could therefore make traction possible, does
not receive any driving force. 4ETS rectifies
this disadvantage and provides good
steerability by braking the spinning wheel
automatically and therefore channeling more
driving force to the wheel that is on a firm
surface and that can therefore supply
traction.
ESP ®
and 4ETS are traction systems that are
ideally suited for driving on roads and on
gentle terrain. The LOW RANGE off-road gear
also improves off-road capability.
Difficult terrain conditions require further
more extensive measures such as the locking
of one or more differentials. Your vehicle is
equipped with two differential locks: one
(central) differential lock for the transfer case
and one differential lock for the rear axle.
Each differential lock can be activated with
the selector wheel on the center console.
When the (central) differential for the transfer
case is locked, the speed of the front wheels
is just as high as the speed of the rear wheels.
If the differential for the rear axle is locked,
both rear wheels turn at the same speed,
regardless of their individual torques. Please
note that activating the differential locks
severely restricts the vehicle's steerability.
For your own safety, the safety of others and
to prevent damage to your vehicle, the
differential locks must not be activated on
paved roads. Please note that the function of
the differential is absolutely necessary for
driving on paved roads and that the
differentials must not be locked on paved
roads under any circumstances. The
steerability of the vehicle would otherwise be208Off-road driving systemsDriving and parking

Allow for enough play in the chains to
facilitate turning tight corners.
R a separate brake system for certain types
of trailer.
R a safety switch for braked trailers. Check
the specific legal requirements applicable
to your federal state.
If the trailer detaches from the towing
vehicle, the safety switch applies the
trailer's brakes.
! Do not connect the trailer's brake system
(if featured) to the hydraulic brake system
of the towing vehicle, as the latter is
equipped 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.
i The vehicle's wiring harness features a
line to the brake indicator lamp.XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XSelect highway level.XVehicles with the adaptive damping
system: set ADS to AUTO or COMF .XSwitch off the engine.XClose all doors and the tailgate.XCouple up the trailer.XEstablish all electrical connections.
i
Vehicles with the AIRMATIC package:
with a trailer attached, the vehicle will
always remain at highway level. When
coupling up a trailer, please observe the
following:
R if highway level has not been set
manually, the vehicle will automatically
sink to highway level as soon as it
reaches a speed of 5 mph (8 km/h).
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.
Towing a trailer
There are numerous legal requirements
concerning the towing of a trailer, e.g. speed
restrictions. Make sure that your vehicle/
trailer combination complies with the local
requirements not only in your area of
residence but also at any location to which
you are traveling. The police and local
authorities can provide reliable information.
Please observe the following when towing a
trailer:
R To acquaint yourself with driving with a
trailer and with the resulting changes to
handling, you should practice cornering,
stopping and reversing in a traffic-free
location.
R Before driving, check:
- the trailer tow hitch
- the safety switch for braked trailers
- the safety chains
- the electrical connections
- the lights
- the wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer features electronically
controlled brakes, pull away the vehicle/
trailer combination carefully, manually
brake using the brake controller, and check
the brakes for correct function.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion.
R If you couple up a trailer, regularly check
the cargo for secure fastening and make
sure that the trailer lamps and (if
applicable) the trailer brakes are
functioning correctly.
R Bear in mind that the handling will be less
stable when towing a trailer than when
Trailer towing211Driving and parkingZ

driving without one. Avoid sudden steering
movements.
R The 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.
R If possible, avoid abrupt braking. Depress
the brake pedal moderately at first, so that
the trailer can activate its own brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission continues to
shift back and forth between two gears
when driving up or downhill, restrict the
shift range. Select shift range 4, 3, 2, or 1.
A lower gear and lower speed reduce the
risk of engine failure.
R On long and steep gradients that are
difficult to drive down in shift range 1,
switch to the off-road drive program or
engage the LOW RANGE off-road gear.
R When 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.
R If the coolant temperature increases
dramatically while the air-conditioning
system is switched on, switch off the air-
conditioning system.
Coolant heat can additionally be dissipated
by opening the windows and by setting the
blower fan and the interior temperature to
maximum.
R When overtaking, pay particular attention
to the extended length of your vehicle/
trailer combination.
Due to the length of your vehicle/trailer
combination, you will have to travel an
additional distance beyond the vehicle you
are overtaking before returning to the
previous lane.Decoupling a trailerGWARNING
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.
XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XClose all doors and the tailgate.XApply the trailer's parking brake.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.
XRemove the trailer cable and decouple the
trailer.XSwitch off the engine.212Trailer towingDriving and parking

Multifunction display
Values and settings as well as display
messages are shown in the multifunction
display.:Trip odometer;Odometer=Transmission position?Status bar with outside temperature or
speed ( Y page 224)
For further information on displaying the
transmission position, see ( Y page 155).
218Displays and operationOn-board computer and displays

XTo select the next/previous track:
briefly press the & or * button.XTo select a track from the track list
(rapid scrolling): press and briefly hold the
& or * button.
The current track will not be displayed in
audio AUX mode ( Auxiliary audio mode:
external audio source connected).
Operating video DVD
XSwitch on COMAND and select video DVD
(see the separate operating instructions).XPress the V or U button on the
steering wheel to select the Audio menu.
DVD changer display (example)
:Current DVD (for DVD changer);Current sceneXPress the & or * button to select a
scene.
Navigation system menu
Displaying navigation instructions
In the Navigation menu: the instructions
from the navigation system appear in the
multifunction display. For more information,
see the separate operating instructions.
XSwitch on COMAND (see the separate
operating instructions).XPress the V or U button on the
steering wheel to select the Navigation
menu.Route guidance inactive
The direction of travel appears in the
multifunction display. If the name of the
street is part of the navigation system data,
this will also be displayed.
Route guidance active
The multifunction display shows navigation
instructions, for example:
Off-road menu
Depending on your vehicle's optional
equipment, you can set the following current
settings to be shown in the Off-road menu:
R Level control ( Y page 189)
R compass ( Y page 296)
R differential locks ( Y page 208)
i Large buildings, power cables or powerful
transmission masts as well as metallic
objects on or in the vehicle may interfere
with the compass display.
XPress V or U on the steering wheel
to select the Offroad menu.222Menus and submenusOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsÆ
Being lowered Max.
12 MPHThe vehicle is being lowered from off-road level 3 to off-road level
2. The display message informs you of the maximum speed
permissible for off-road level 3.XDo not drive faster than 12 mph (20 km/h) until off-road level 2
has been reached.8
Locking System
Inoperative
Service RequiredThe differential locks are defective.XDo not drive faster than 50 mph (80 km/h).XHave the vehicle checked at a qualified specialist workshop.8
Diff. Lock System
Overheated - Wait
briefly.The differential locks are too hot and have been disengaged.XDrive on carefully.XAllow the differential locks to cool down.
The differential locks reengage as soon as they have cooled
down.8
Stop vehicle,
engage parking
brakeA gearshift process has been canceled. LOW RANGE is in the
neutral position. There is no connection between the engine and
the drive wheels.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake. Do not continue driving under any
circumstances.XRepeat the gearshift process.Å
Service Required
If parked engage
pk. brakeLOW RANGE is malfunctioning.XDo not drive faster than 50 mph (80 km/h).XEngage the parking brake to park.XHave the vehicle checked at a qualified specialist workshop.Å
Max. Speed 25 MPHYou have exceeded the maximum speed for the gearshift process.XDrive slower.
The gearshift process is carried out.Å
Max. Speed 40 MPHYou have exceeded the maximum speed for the gearshift process.XDrive slower.
The gearshift process is carried out.Å
Shift briefly into
NYou have reduced the vehicle speed, but the automatic
transmission is not in position N.XBriefly shift the automatic transmission to position N.Display messages249On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutionsh
Tire Pressure
Caution: Tire
DefectGRisk of accident
The tire pressure in one or more tires has dropped suddenly.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 362).h
Tire Pressure
Check TiresGRisk of accident
The tire pressure in one or more tires has dropped significantly.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 362).XCheck the tire pressure. If necessary, correct the tire pressure
( Y page 347).h
Please correct the
tire pressuresThe tire pressure is too low in at least one of the tires or the tire
pressure difference between the wheels is too great.XCheck the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 347).
Vehicle
Display messagesPossible causes/consequences and M SolutionsShift to P or N
to start engine.You have attempted to start the engine with the transmission in
position R or D.XShift the transmission to position P or N.Auxiliary Battery
MalfunctionThe auxiliary battery for the automatic transmission is no longer
being charged.XVisit a qualified specialist workshop at the next opportunity.XUntil then, set the automatic transmission to position P before
you switch off the engine.XBefore leaving the vehicle, apply the parking brake.Depress brake to
shift out of P.You have attempted to move the transmission selector lever to
position D, R or N without depressing the brake pedal.XDepress the brake pedal.254Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsDoor Open
Vehicle Not In ParkThe driver's door is open and the transmission is in position R, N
or D.XShift the transmission to position P.XEngage the parking brake.Drive to workshop
without shifting
gears.You cannot change the transmission position due to a malfunction.
If transmission position D is selected:XDrive to a qualified specialist workshop without shifting the
transmission from position D.
If transmission position R, N or P is selected:
XNotify a qualified specialist workshop or breakdown service.Only shift to P
when vehicle is at
a standstill.The vehicle is moving.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XShift the transmission to position P.EGRisk of accident
The hood or the tailgate is open.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XClose the hood or tailgate.You have attempted to lock the vehicle with KEYLESS-GO while
the tailgate or door is open.XClose all the doors and/or the tailgate.;At least one door is open.XClose all the doors.D
Power Steering
Malfunction See
Operator's ManualGRisk of accident
The power steering assistance is defective.
You will need to use more force to steer.
XCheck whether you are able to apply the extra force required.XIf you are able to steer safely: carefully drive on to a qualified
specialist workshop.XIf you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop.Display messages255On-board computer and displaysZ