2012 MERCEDES-BENZ GL-Class engine

Activating/deactivating DSR
Activating
DSR can only be activated if you are driving
no faster than 20 mph (30 km/h).
Vehicle without the Off-Road Pro Engineering
package
Vehicle with the Off-Road Pro Engineering package
XPress button :.
Indicator lamp ; lights up.
The DSR symbol and a message, such as the
following, appear in the multifunction display:
If the speed that is being driven is too high,
the DSR symbol and the Max. speed
20 mph (Canada: 30 km/h) message appears
in the multifunction display.
DeactivatingXPress button :.
Indicator lamp ; goes out.
The DSR symbol appears in the
multifunction display with the Off
message.
DSR is deactivated automatically if you are
driving faster than 21 mph (Canada:
35 km/h). The DSR symbol appears in the
multifunction display with the Off message.
You also hear a warning tone.
Changing the set speed while
the vehicle is in motion
When DSR is activated, the control speed can
be changed to a value between 3 mph and
10 mph (Canada: between 4 km/h and
18 km/h) during the journey.
XTo increase or decrease in 1 mph
(Canada: 1 km/h) increments: press the
cruise control lever to the point of
resistance briefly upwards : for a higher
control speed or briefly downwards ; for
a lower control speed.
The set value appears in the multifunction
display.XTo increase or decrease in 5 mph
(Canada: 10 km/h) increments: push the
cruise control lever beyond the point of
resistance briefly upwards : for a higher
control speed or briefly downwards ; for
a lower control speed.
The set value appears in the multifunction
display.Off-road driving systems205Driving and parkingZ

Off-road drive program
i The off-road drive program is available
only in vehicles without the Off-Road Pro
engineering package.
The off-road drive program assists you in
driving off-road. The engine’s performance
characteristics and the gearshifting
characteristics of the automatic transmission
are adapted for this purpose. ABS, ESP ®
and
4 ETS programs especially adapted to off-
road driving are also activated.
Do not use the off-road drive program on
roads that are covered in snow or icy or if you
have installed snow chains on your vehicle.
For information about driving off-road, see
( Y page 174).XTo activate: press off-road button :.
Indicator lamp ; lights up. Off-road
indicator = appears in the multifunction
display.XTo activate: press off-road button :.
Indicator lamp ; and off-road indicator
= go out.LOW RANGE off-road gear
General notes
The LOW RANGE off-road gear assists you in
driving off-road and when fording. When LOW
RANGE is engaged, the engine’s performance
characteristics and the gearshifting
characteristics of the automatic transmission
are adapted for this purpose. ABS, ESP ®
and
4 ETS programs especially adapted to off-
road driving are also activated.
Information on "Off-road driving"; see
( Y page 174) . You will find information about
driving safety systems in conjunction with
LOW RANGE in the "Safety" section
( Y page 67).
Shift ranges
HIGH RANGERoad position for all
normal driving situationsLOW RANGEOff-road position for
driving off-road and
fording
The gear ratio between the
engine and wheels is only
approximately one third of
that in the HIGH RANGE
road position. The drive
torque is correspondingly
higher as a result.
Do not use LOW RANGE:
R on slippery road
surfaces, e.g. in the case
of slush
R on snow or ice-covered
roads
R if you have snow chains
on your vehicleGWARNING
Always wait until the procedure of shifting
from HIGH RANGE to LOW RANGE – and from
LOW RANGE to HIGH RANGE – has been
entirely completed. During this procedure do
206Off-road driving systemsDriving and parking

not turn off the engine or shift the automatic
transmission into another gear.
If you do not wait until the shifting procedure
has been entirely completed then it might not
be correctly performed. The transfer case
might be in neutral, thus interrupting the
transfer of power between the engine and the
drive axle.
The vehicle is then freely movable, even if a
gear has been selected, and could
unintentionally be set into motion –
particularly on up – or downhill grades. This
could lead to an accident and cause injury to
yourself and others.
Please observe related messages appearing
in the multifunction display.
From HIGH RANGE to LOW RANGE
! Only carry out the gear change process if:
R the engine is running
R the transmission is in position N
R you are not driving faster than
25 mph (40 km/h)
XPress LOW RANGE button :.
Indicator lamp ; flashes. LOW RANGE
indicator = appears in the multifunction
display.When the gear change is complete,
indicator lamp ; lights up.
While indicator lamp ; is flashing, you can
cancel the gear change by pressing LOW
RANGE button : again.
From LOW RANGE to HIGH RANGE
! Only carry out the gear change process if:
R the engine is running
R the transmission is in position N
R you are not driving faster than 43 mph
(70 km/h)
XPress LOW RANGE button :.
Indicator lamp ; flashes.
If the gear change process has taken place,
indicator lamp ; and LOW RANGE
indicator = in the multifunction display go
out.
While indicator lamp ; is flashing, you can
cancel the gear change by pressing LOW
RANGE button : again.
Messages in the multifunction display
If a gear change process has not been
successful, the following messages may be
displayed in the multifunction display:
Drive max. 25 mph (Canada: 40 km/h): You
have driven faster than 25 mph (40 km/h).
Indicator lamp ; also flashes.
XDrive more slowly to carry out the gear
change process.
Briefly engage gear N : The transmission
is in position D and you are now driving below
25 mph (40 km/h).
XShift the transmission to N to complete the
gear change process.
Shifting process canceled
Reactivate : The shifting process has not
been completed.
XMaintain all gear change conditions and
carry out the gear change process again.
Stop vehicle Apply parking brake : A
warning tone is also heard. The gear change
Off-road driving systems207Driving and parkingZ

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

lost and steering would no longer be possible.
The differential locks must therefore only be
activated off-road and only if activating the
other driving systems (4ETS, ESP ®
and LOW
Range off-road gear) is no longer sufficient.
Engaging the differential locks
! Pull away slowly when the differential
locks are activated.
Function or performance tests may only be
performed on a 2-axle dynamometer. If you
wish to operate the vehicle on such a
dynamometer, please consult an
authorized Mercedes-Benz Center
beforehand. You could otherwise damage
the drive train or the brake system.
Automatic mode
Use automatic mode ; for all driving
situations, including driving off-road or when
fording.
In automatic mode, the differential locks are
engaged and disengaged according to driving
requirements. This guarantees sufficient
traction for most driving situations with
unrestricted vehicle steerability.
XStart the engine.
The differential locks are in automatic
mode. The indicator lamp in selector
wheel : lights up above symbol for
automatic mode ;.Engaging manuallyGWARNING
Never drive on a paved surface with the center
and rear axle differential locks manually
engaged. Ability to steer the vehicle is greatly
reduced when the differential locks are
manually engaged, increasing the risk of an
accident.
For safety reasons, the locks are
automatically released at a vehicle speed
above 31 mph (50 km/h). Nevertheless, you
should only manually lock the differential if
absolutely necessary because engaged locks
will restrict the vehicle drivetrain while
cornering and cause the vehicle to chatter.
This could cause you to lose control of the
vehicle and cause an accident.
! The differential locks must not be
activated when the vehicle is being towed
or while the wheels are spinning.
Only engage the differential locks manually if
traction in automatic mode is insufficient.
The differential locks can be activated
manually up to a speed of 19 mph
(30 km/h).
XStart the engine.XTurn selector wheel : to desired position
= or ?.
The indicator lamp in selector wheel :
lights up at the corresponding symbol.
The engaged differential appears in the
multifunction display:
AThe differential lock for the transfer case
is locked.
If you have not previously selected the off-
road menu ( Y page 222) in the on-board
Off-road driving systems209Driving and parkingZ

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

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 24).
Important safety notes
You will find an illustration of the instrument
cluster in the "At a glance" section
( Y page 29).
GWARNING
A driver's attention to the road and traffic
conditions must always be his/her primary
focus when driving.
For your safety and the safety of others,
selecting features through the multifunction
steering wheel should only be done by the
driver when traffic and road conditions permit
it to be done safely.
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.
GWARNING
No messages will be displayed if either the
instrument cluster or the multifunction
display is inoperative.
As a result, you will not be able to see
information about your driving conditions,
such as
R speed
R outside temperature
R warning/indicator lamps
Rmalfunction/warning messages
R failure of any systems
Driving characteristics may be impaired.
If you must continue to drive, do so with added
caution. Contact an authorized Mercedes-
Benz Center as soon as possible.GWARNING
Malfunction and warning messages are only
indicated for certain systems and are
intentionally not very detailed. The
malfunction and warning messages are
simply a reminder with respect to the
operation of certain systems. They do not
replace the owner's and/or driver's
responsibility to maintain the vehicle's
operating safety. Have all required
maintenance and safety checks performed on
the vehicle. Bring the vehicle to an authorized
Mercedes-Benz Center to address the
malfunction and warning messages.
Displays and operation
Tachometer
The red band in the tachometer indicates the
engine's overrevving range.
! Do not drive in the overrevving range, as
this could damage the engine.
The fuel supply is interrupted to protect the
engine when the red band is reached.
Outside temperature display
The outside temperature display is in the
multifunction display ( Y page 218).
GWARNING
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
216Displays and operationOn-board computer and displays