
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 67)controls the
balance between the wheels on the front axle.
Information on "Off-road driving"; see
( Y page 166).
Information about the differential and
differential locks
When the vehicle is driving around a curve,
the wheels on the outside of the curve have
to cover a greater distance and therefore
have to turn faster than the wheels on the
inside. The differential, a transmission in the
drive train, balances these different rotational
speeds out, making cornering possible.
The disadvantage of a differential: the wheels
with the least grip are driven the hardest.
Example: one wheel on a driven axle is on a
snow-covered surface and therefore has no
traction. This wheel has the most driving
force, since the differential distributes most
of the force to the wheel with the least
resistance. The wheel on the opposite side of
this axle, which is on a solid surface and could
therefore enable traction, does not have any
driving force. 4ETS eliminates this
disadvantage and ensures good steerability
by braking the spinning wheel automatically
and thereby directing more force to the wheel
that is on a solid surface and can provide
traction.
ESP ®
and 4ETS are traction systems that are
ideally suited to road driving and driving on
easily negotiable off-road terrain. The LOW
RANGE off-road gear also improves off-road
capability.
Difficult off-road conditions require additional
measures, such as locking one or more
differentials. Your vehicle has two differential
locks: one (central) differential lock for the
transfer case and one differential lock for the
rear axle. Both differential locks can be
activated using the selector wheel on the
center console. When the (central)
differential for the transfer case is locked, the
speed of the front wheels is the same as the
speed of the rear wheels. When the
differential for the rear axle is locked, both of
the rear wheels turn at the same speed,
independent of their individual torques. Note
that activating the differential locks
significantly reduces the steerability of the
vehicle.
For your safety, the safety of others and to
prevent damage to the vehicle, the
differential locks must not be activated on
paved roads. Note that the differential
function is necessary when driving on paved
roads and that the differentials must never be
locked on paved roads. Otherwise, the
vehicle can no longer be steered. The
differential locks must therefore only be
activated when driving off-road, and then only
if activating the other driving systems (4ETS,
ESP ®
and LOW RANGE off-road gear) is no
longer sufficient.
Engaging the differential locks
! Drive off slowly when the differential
locks are engaged.
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.
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XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XVehicles with the AIRMATIC package:
select 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 coupling
- 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
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
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ROn long and steep gradients that are
difficult to drive down in shift range 1,
switch to the off-road drive program.
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 trailer
GWarning!
Vehicles with air suspension program: 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
switch 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!
Vehicles with air suspension program: 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.
XDetach the trailer cable and decouple the
trailer.XDetach the trailer cable and decouple the
trailer.XSwitch off the engine.
Permissible trailer load and drawbar
noseweight
Weight specifications
The Gross Trailer Weight (GTW) is the
combined weight of the trailer together with
the cargo and equipment loaded on the
trailer. Permissible gross weight:
R Vehicles with 4MATIC: 7200 lb (3265 kg)
R Vehicles without 4MATIC: 4630 lb
(2100 kg)
The permissible Trailer drawbar Weight
Rating (TWR) is the maximum weight
permitted on the trailer drawbar:
R Vehicles with 4MATIC: 576 lb (261 kg) limit
for Mercedes-Benz-approved trailer
couplings
R Vehicles without 4MATIC: 370 lb (168 kg)
limit for Mercedes-Benz-approved trailer
couplings
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XPress V or U on the steering wheel
to select the standard display.XPress the & or * button to select
digital speedometer or the outside
temperature.
Digital speedometer
Outside temperature
AMG menu in AMG vehicles
AMG displays
XPress V or U on the steering wheel
to select the AMG menu. :Gear indicator;Upshift instruction=Engine oil temperature
If the engine reaches the overrevving range in
the manual gearshift program, the menu is
displayed in red. You will also see shift up
instruction ;. Shift up instruction ;
overrides other messages in the
multifunction display until you have shifted
up.
When the engine temperature is below
80 †, the oil temperature gauge flashes.
Avoid driving at full engine output during this
time.
Displaying the on-board voltageXPress V or U on the steering wheel
to select the AMG menu.XPress the & button repeatedly until the
on-board voltage is shown.:Gear indicator;On-board voltage
RACETIMER
Displaying and starting RACETIMER
GWarning
The RACETIMER feature is only for use on
roads and in conditions where high speed
driving is permitted. Racing on public roads is
prohibited under all circumstances. The driver
is and must always remain responsible for
following posted speed limits.
You can use the RACETIMER to store lap
times.
When RACETIMER is displayed, you cannot
adjust the volume using the W and X
buttons on the steering wheel.
XPress V or U on the steering wheel
to select the AMG menu.XPress the & button repeatedly until the
RACETIMER is shown.Menus and submenus209On-board computer and displaysBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 209Z

You can select Km or Miles as the unit of
measurement for distance ( Y page 214).
Resetting valuesXPress V or U on the steering wheel
to select the trip computer menu. XPress & or * to select the function
that you wish to reset.XPress and hold the . reset button on the
instrument cluster until the values have
reverted to "0".
Calling up the range
XPress V or U on the steering wheel
to select the trip computer menu.XPress & or * to select Range:.
The multifunction display shows the
estimated range of the vehicle, based on
the current driving style and the fuel level.
If there is only a small amount of fuel
remaining in the fuel tank, a vehicle
refueling C appears instead of the
range.
Displaying the current fuel
consumption
XPress V or U on the steering wheel
to select the trip computer menu.XPress & or * to select
Consumption .
The current fuel consumption is
displayed 37
.Telephone menu
Introduction
You can establish a Bluetooth ®
wireless
connection to COMAND APS (see the
separate operating instructions).
GWarning
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 while driving, please use the hands-
free device and only use the telephone when
weather, road and traffic conditions permit.
Some jurisdictions prohibit the driver from
using a mobile phone while driving a vehicle.
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.
XSwitch on the mobile phone and COMAND
APS (see the separate operating
instructions).XPress V or U on the steering wheel
to select the Telephone menu.
You will see one of the following display
messages in the multifunction display:
R Ready or the name of the network provider:
the mobile phone has found a network and
is ready to receive.
R No Service : No network is available.
Accepting a call
If someone calls you when you are in the
Telephone menu, a display message appears
in the multifunction display, for example:
37 Not in AMG vehicles.220Menus and submenusOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsCThere is only a small amount of fuel in the fuel tank.XRefuel at the nearest gas station.8
Reserve FuelThe fuel level has fallen below the reserve range.
The fuel tank must be filled up to at least the reserve fuel level;
otherwise, engine running may be impaired.XRefuel at the nearest gas station.8
Gas Cap OpenThe fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.XCheck that the fuel filler cap is correctly closed.XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.XIf the fuel filler cap is closed: visit a qualified specialist
workshop.8
Ultra Low-sulfur
Diesel Fuel OnlyVehicles with a diesel engine: the fuel level has fallen below the
reserve range.XCheck that the fuel filler cap is correctly closed.XRefuel at the nearest gas station.XOnly use commercially available vehicular ULTRA-LOW SULFUR
DIESEL FUEL (ULSD, 15 ppm SULFUR MAXIMUM).¸
Replace air filterVehicles with a diesel engine: the engine air filter is contaminated
and must be replaced. XVisit a qualified specialist workshop.·
Clean Fuel FilterVehicles with a diesel engine: there is water in the fuel filter. The
water must be drained off. XVisit a qualified specialist workshop.Ø
Check Additive See
Operator's ManualThe AdBlue ®
tank is empty.XHave the AdBlue ®
tank filled as soon as possible at a qualified
specialist workshop ( Y page 156).
Visit a qualified specialist workshop.Ø
Remaining Starts:
20The AdBlue ®
level has fallen to a minimum.XHave the AdBlue ®
tank filled as soon as possible at a qualified
specialist workshop ( Y page 156).
Visit a qualified specialist workshop.236Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsÆ
Reduce speed to
under 12 MPHGRisk of accident
You are exceeding the speed permissible for the selected off-road
level.
XAdjust your driving style to the altered handling characteristics.XOnly make slight steering movements and avoid fast steering
movements.XTake account of the altered handling characteristics.XDo not driver faster than 12 mph(20 km/h).8
Locking System
Inoperative
Service RequiredThe differential locks are faulty. 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
brieflyThe 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. brakeThe LOW RANGE system 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.238Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsÅ
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.Å
Shifting Process
Canceled
ReactivateThe gearshift process has been canceled.XRepeat the gearshift process.Ã
InoperativeDSR (Downhill Speed Regulation) is deactivated due to a
malfunction.XHave DSR checked at a qualified specialist workshop.Blind Spot Assist
Currently
Unavailable See
Operator's ManualBlind Spot Assist is temporarily inoperative if:
R the sensors are dirty.
R its function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R the on-board voltage is too low.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
Blind Spot Assist is operational again and the display message
disappears when:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the sensors are fully available again.
R the radar sensor system is back within the operating
temperature range.
If the display message continues to be displayed:XClean the sensors ( Y page 291).XRestart the engine.Blind Spot Assist
InoperativeBlind Spot Assist is faulty.
The yellow 9 indicator lamps also light up in the exterior
mirrors.XVisit a qualified specialist workshop.Cruise Control
InoperativeCruise control is faulty. XVisit a qualified specialist workshop.Display messages239On-board computer and displaysBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 239Z