
dynamometer, please consult an
authorized Mercedes-Benz Center
beforehand. You could otherwise damage
the drive train or the brake system.
Information on "Off-road driving"; see
( Y page 166).
DSR (Downhill Speed Regulation)
Important safety guidelines
DSR is an aid to assist you when driving
downhill. It keeps the speed of travel at the
speed selected on the on-board computer.
The steeper the downhill gradient, the greater
the DSR braking effect on the vehicle. When
driving on flat stretches of road or on an uphill
gradient, the DSR braking effect is minimal or
non-existent.
The speed is set to 4 mph (6 km/h) at the
factory; you can adjust this in the on-board
computer ( Y page 219).
GWarning!
Downhill Speed Regulation (DSR) is a
convenience system designed to assist the
driver during vehicle operation. The system
setting must be appropriate to the
topographical and weather conditions
encountered, which can change quickly. The
driver is responsible for the vehicle speed and
for safe brake operation at all times.
Depending on the programmed speed, actual
vehicle speed and gradient, switching on DSR
while driving can cause the vehicle to slow
down rapidly, and you may hear a sound,
caused by the activation of the vehicle's brake
system through DSR. Sudden and unexpected
deceleration can result in loss of vehicle
control, causing an accident and/or serious
personal injury to you and others. Do not
switch on DSR in a situation where rapid
deceleration could result in a loss of vehicle
control.
DSR controls the set speed when it is active
and the automatic transmission is in the D,
R or N position. You can drive at a higher or
a lower speed than that set on the on-board
computer at any time by accelerating or
braking.GWarning!
If you depress the accelerator pedal with DSR
activated, the vehicle can drive faster than the
programmed set speed. You should therefore
drive downhill with particular caution as it
could lead to an accident and/or serious
injury to you or others. Keep in mind that as
soon as you remove your foot from the
accelerator pedal with DSR switched on, DSR
will start regulating the vehicle's speed
including use of brakes if required. Depending
on the programmed set speed, actual vehicle
speed and gradient, DSR can cause the
vehicle to slow down rapidly. Sudden and
unexpected deceleration can result in loss of
vehicle control, causing an accident and/or
serious personal injury to you and others.
Information on "Off-road driving"; see
( Y page 166).
Activating/deactivating DSR
Activating
You can only activate DSR when driving at
speeds below 20 mph (30 km/h).
XPress button :.
Indicator lamp ; lights up.
The DSR symbol and a message such as the
following appear in the multifunction display:
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All models except AMG vehiclesXTo 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
4ETS programs especially adapted to off-road
driving are also activated.
For information on "Off-road driving", see
( Y page 166) . You will find information about
driving safety systems in conjunction with
LOW RANGE in the "Safety" section
( Y page 65).
Shift rangesHIGH 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 mounted
snow chains to 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
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.
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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 RANGEindicator = 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:
Max. Speed 25 Mph (Canada: 40 Km/h): you
have been driving faster than 25 mph
(40 km/h). Indicator lamp ; also flashes.
XDrive more slowly to carry out the gear
change process.
Shift briefly into N : the transmission is
in position D and you are driving slower than
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.
XEnsure that all gear change conditions are
fulfilled and carry out the gear change
process again.
Stop vehicle, engage parking brake :
a warning tone is also heard. The gear change
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, engage
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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 manually
GWarning!
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.
At speeds of up to 19 mph (30 km/h), you
can engage the differential locks manually.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 213) in the on-board
computer, the message disappears after
about five seconds.
The differential locks are not controlled
automatically. The steerability of the vehicle
is restricted considerably. Drive carefully and
accelerate gently for optimum traction.
! If the differential locks are activated
manually, the wheels scuff on the road
when cornering since the rotation
difference between the wheels is no longer
balanced out.
You can switch back to automatic mode at
any time. For safety reasons, the differential
locks disengage automatically at speeds
above 31 mph (50 km/h). If you stop the
vehicle and switch off the ignition for longer
than ten seconds, the differential locks
switch back to automatic mode.
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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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XPress W or X to select the display in
the status line: speed ( Speed) or outside
temperature ( Outside Temperature ).
The selected display now appears
constantly in the lower multifunction
display. When you scroll through the
Standard display menu (Y page 208), you
will see the display you have not selected.XPress the &, V or U button to
select a different display.
Time/date
Only vehicles without the navigation module
have this submenu. To set the time and date
on vehicles without the navigation module,
see the separate operating instructions.
In the Time / Date submenu, you can set the
time and date.
XPress V or U on the steering wheel
to select the Settings menu.XPress & to call up the selection of
submenus.XPress the W or X button to select the
Time / Date submenu.XTo set the clock: press & on the
steering wheel to select Clock Set hour
or Clock Set Minute(s) .
or
XTo set the date: press & to select
Date Set day , Date Set Month or Date
Set Year .XPress W or X to set a value.XPress the &, V or U button to
select a different display.
Lighting
Switching the daytime running lamps on/
off
This function is not available in Canada.
If you have activated the daytime running
lamps function and the light switch is in the
$ or à position, the daytime running
lamps are switched on automatically when
the engine is running.
In the dark, the following also light up:
R the low-beam headlamps
R the parking lamps
R the tail lamps
R the license plate lamp
R the side marker lampsXPress V or U on the steering wheel
to select the Settings menu.XPress & to call up the selection of
submenus.XPress the W or X button to select the
Lighting submenu.XPress & to select Daytime Running
Lamps .XPress W or X to set daytime running
lamps to On or Off .XPress the &, V or U button to
select a different display.
Switching the surround lighting on/off
If you activate the surround lighting function
and the light switch is set to Ã, the
following will light up if it is dark and you
unlock the vehicle using the SmartKey:
R the parking lamps
R the license plate lamp
R the tail lamps
R the fog lamps 33
R the low-beam headlamps 34
R the side marker lamps
The surround lighting switches off
automatically after 40 seconds or when the
driver's door is opened.
33 Only for vehicles with front fog lamps.
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XPress V or U on the steering wheel
to select the Settings menu.XPress & to call up the selection of
submenus.XPress the W or X button to select the
Lighting submenu.XPress & to select Surround Lighting
Function .XPress the W or X button to activate
or deactivate the Surround Lighting
function.XWhen leaving the vehicle, turn the light
switch to position Ã.
The surround lighting is activated.XPress the &, V or U button to
select a different display.
Setting the ambient lighting
This function is only available in the "Grand
Edition" model.
XPress V or U on the steering wheel
to select the Settings menu.XPress & to call up the selection of
submenus.XPress the W or X button to select the
Lighting submenu.XPress the & button to select Ambient
Light .XPress W or X to adjust the
brightness to any level from Level 0 (off)
to Level 5 (bright).XPress the &, V or U button to
select a different display.
Activating/deactivating the exterior
lighting delayed switch-off
When you activate the Headlamp Delayed
Shut-off function and the light switch is set
to à , the exterior lighting remains on for
another 15 seconds after closing the doors
when it is dark.
If the engine is switched off and then none of
the doors are opened, or if an open door is
not closed, the exterior lighting goes out after
60 seconds.
If you have activated the delayed switch-off
function, the light switch is set to à and
you switch off the engine, the following
remain lit:
R the parking lamps
R the license plate lamp
R the tail lamps
R the fog lamps 35
R the low-beam headlamps 36
R the side marker lampsXPress V or U on the steering wheel
to select the Settings menu.XPress & to call up the selection of
submenus.XPress the W or X button to select the
Lighting submenu.XPress the & button to select Headlamp
Delayed Shut-off .XPress the W or X button to activate
or deactivate the Headlamp Delayed
Shut-off function.XBefore switching off the engine, turn the
light switch to position Ã.
The exterior lighting delayed shut-off is
activated.XPress the &, V or U button to
select a different display.
To deactivate the delayed shut-off
temporarily:
XBefore leaving the vehicle, turn the
SmartKey to position 0 in the ignition lock.XTurn the SmartKey to position 2 in the
ignition lock and back to position 0.
The delayed shut-off is deactivated.
The delayed shut-off is reactivated the next
time you start the engine.
35 Only for vehicles with front fog lamps.
36 Only for vehicles without front fog lamps.216Menus and submenusOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Enabled
See Operator's
ManualThe front-passenger air bag is enabled during the journey,
although:
R there is a child, a small adult or an object weighing less than the
system's weight threshold is on the front-passenger seat.
R the front-passenger seat is unoccupied
The system may detect the additional weight of objects on the
seat or forces acting on the seat.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XOpen the front-passenger door.XRemove the child and the child restraint system from the front-
passenger seat.XIf necessary, secure the child in a child restraint system on a
suitable rear seat.XMake sure that no forces are acting on the seat, such as:
R trapped books, bags, etc. lying on, behind or beside the seat
R head restraints pressing against the headliner
The system may otherwise detect these forces and interpret the
seat occupant's weight as greater than it actually is.XMake sure that the seat is unoccupied and has no objects placed
on it, close the front-passenger door, and switch on the ignition.
Observe the 42 indicator lamps (Y page 42) and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 42 indicator lamp must light up and remain lit.
When the indicator lamp is on, OCS ( Y page 42) has disabled
the front-passenger air bag.
R the display messages Front Passenger Airbag Enabled
See Operator's Manual or Front Passenger Airbag
Disabled See Operator's Manual must not appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are met, the front-passenger seat can be
occupied again. Whether the 42 indicator lamp
remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are not met, the system is not operating correctly.
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