display MERCEDES-BENZ R-Class 2012 W251 Workshop Manual

the vehicle's speed to the last speed stored
after you have finished overtaking.
DISTRONIC is automatically deactivated if:
R you apply the parking brake.
R you are driving slower than
20 mph (25 km/h) and there is no vehicle
in front, or if the vehicle in front is no longer
detected.
R ESP ®
intervenes or you deactivate ESP ®
.
R you shift the transmission to P, R or N.
If DISTRONIC is deactivated, you will hear a
warning tone. You will see the DISTRONIC
Off message in the multifunction display for
approximately five seconds.
Tips for driving with DISTRONIC
The following contains descriptions of certain
road and traffic conditions in which you must
be particularly attentive. In such situations,
brake if necessary. DISTRONIC is then
deactivated.
GWARNING
The Distronic works to maintain the speed
selected by the driver unless a moving
obstacle proceeding directly ahead of it in the
same travel direction is detected (e.g.
following another vehicle ahead of you at your
set distance).
This means that:
R Your vehicle can pass another vehicle after
you have changed lanes.
R While in a sharp turn or if the preceding
vehicle is in a sharp turn, the Distronic
could lose sight of the preceding vehicle.
Your vehicle could then accelerate to the
previously selected speed.
The Distronic regulates only the distance
between your vehicle and those directly
ahead of it, but does not register stationary
objects in the road, e.g.:
R a stopped vehicle in a traffic jam
R a disabled vehicle
R an oncoming vehicle
The driver must always be alert, observe all
traffic and intercede as required by means of
steering or braking the vehicle.GWARNING
The Distronic should not be used in snowy or
icy road conditions.
Cornering, going into and coming out of a
bend
The ability of DISTRONIC to detect vehicles
when cornering is limited. Your vehicle may
brake unexpectedly or late.
Vehicles traveling on a different line
DISTRONIC may not detect vehicles traveling
on a different line. The distance to the vehicle
in front will be too short.
Driving systems179Driving and parkingZ

The vehicle is automatically lowered to high-
speed level when you:
R drive faster than 70 mph (112 km/h)
R drive between 60 mph (96 km/h) and
70 mph (112 km/h) for approximately
20 seconds.
The individual vehicle levels differ from
highway level as follows:
R +1.97 in (+ 50 mm) at the raised level
R +/-0 in (+/-0 mm) at the highway level
R -0.47 in (-12 mm) at the high-speed level
i The high-speed level is not available if you
are pulling a trailer. Observe the notes on
driving with a trailer ( Y page 191).
i Observe the speed limitations. Drive
carefully at an appropriate speed.
Raised level
Only select raised level when this is
appropriate for the road conditions.
Otherwise, fuel consumption may increase
and handling may be affected.
If you select the raised level at a speed of over
40 mph (64 km/h) the Level Selection
Not Permitted message appears in the
multifunction display.XStart the engine.
Indicator lamp ; is not lit:
XPress button :.
Indicator lamp ; flashes. The vehicle rises
to raised level.While the adjustment is taking place, a
message appears in the multifunction
display, e.g.:
If you press the V, U , * or &
button on the multifunction steering wheel,
the message will disappear.
Once the vehicle has reached raised level,
indicator lamp ; remains lit. A message
appears in the multifunction display for
approximately five seconds, e.g.:
The level is automatically taken up to highway
level if you drive faster than 25 mph
(40 km/h).
Highway level
! Make sure that there is enough ground
clearance when the vehicle is being
lowered. It could otherwise hit the ground,
damaging the underbody.
XMake sure that the doors are closed.XStart the engine.182Driving systemsDriving and parking

If indicator lamp ; is lit:XPress button :.
Indicator lamp ; flashes. The vehicle is
lowered to highway level.
While the adjustment is taking place, a
message appears in the multifunction
display, e.g.:
If you press the V, U , * or &
button on the multifunction steering wheel,
the message will disappear.
Once highway level has been reached,
indicator lamp ; goes out. A message
appears in the multifunction display for
approximately five seconds, e.g.:
The level is automatically raised from high-
speed level to highway level if the speed falls
below 40 mph (64 km/h). The level is
automatically taken up to highway level if you
drive faster than 25 mph (40 km/h).
4MATIC (permanent four-wheel drive)
4MATIC ensures that all four wheels are
permanently driven. Together with ESP ®
and
4ETS , it improves the traction of your vehicle
whenever a drive wheel spins due to
insufficient grip.
GWARNING
If a drive wheel is spinning due to insufficient
traction:
R While driving off, apply as little throttle as
possible.
R While driving, ease up on the accelerator
pedal.
R Adapt your speed and driving style to the
prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The 4MATIC cannot prevent accidents
resulting from excessive speed.
! Never tow the vehicle with one axle
raised. This may damage the transfer case.
Damage of this sort is not covered by the
Mercedes-Benz Limited Warranty. All
wheels must remain either on the ground
or be fully raised. Observe the instructions
for towing the vehicle with all wheels in full
contact with the ground.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires ( M+S tires), with snow
chains if necessary.
! When testing the parking brake, operate
the vehicle only briefly (for a maximum of
ten seconds) on a brake test dynamometer.
When doing this, turn the key to position
0 or 1 in the ignition. Failure to do this can
cause damage to the drive train or the
brake system.
! 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.
Driving systems183Driving and parkingZ

! When parking, pay particular attention to
objects above or below the sensors, such
as flower pots or trailer drawbars.
PARKTRONIC does not detect such objects
when they are in the immediate vicinity of
the vehicle. You could damage the vehicle
or the objects.
The sensors may not detect snow and other
objects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic
car wash, the compressed-air brakes on a
truck or a pneumatic drill could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
Minimum distanceCenterApproximately 8 in
(approximately 20 cm)CornersApproximately 6 in
(approximately 15 cm)
If there is an obstacle within this range, the
relevant warning displays light up and a
warning tone sounds. If the distance falls
below the minimum, the distance may no
longer be shown.
Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located
on the dashboard above the center air vents.
The warning display for the rear area is in the
roof lamp in the rear compartment.
Warning display for the front area
:Segments on the left-hand side of the
vehicle;Segments on the right-hand side of the
vehicle=Segments showing operational readiness
The warning display for each side of the
vehicle is divided into five yellow and two red
segments. PARKTRONIC is operational if
yellow segments showing operational
readiness = light up.
The selected transmission position
determines which warning display is active
when the engine is running.
Transmission
positionWarning displayDFront area activatedR or NRear and front areas
activatedPNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
From the:
R sixth segment onwards, you will hear an
intermittent warning tone for
approximately two seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two
seconds. This indicates that you have now
reached the minimum distance.
Driving systems185Driving and parkingZ

Problems with PARKTRONICProblemPossible causes/consequences and M SolutionsOnly the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is
deactivated after
approximately
20 seconds, and the
indicator lamp in the
PARKTRONIC button
lights up.PARKTRONIC has malfunctioned and has switched off.XIf problems persist, have PARKTRONIC checked at a qualified
specialist workshop.Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is
deactivated after
approximately 20
seconds.The PARKTRONIC sensors are dirty or there is interference.XClean the PARKTRONIC sensors ( Y page 291).XSwitch the ignition back on.The problem may be caused by an external source of radio or
ultrasound waves.XSee if PARKTRONIC functions in a different location.Rear view camera
Important safety notes
The rear view camera is an optical parking aid.
It shows the area behind your vehicle in the
COMAND display.
GWARNING
Make sure that no persons or animals are in
the maneuvering range. Otherwise, they
could be injured.
The rear view camera is located in the handle
strip of the tailgate.
:Rear view camera
View through the camera
The area behind the vehicle is displayed as a
mirror image, as in the rear-view mirror.
Driving systems187Driving and parkingZ

GWARNING
The rear view camera is only an aid and may
display obstacles
R from a distorted perspective
R inaccurately
R may not display obstacles at all
The rear view camera does not relieve you of
the responsibility to be cautious. Take care
and pay careful attention. The rear view
camera may not show objects which are
R very close to the rear bumper
R under the rear bumper
R above the tailgate handle
You are responsible for safety at all times and
must continue to pay attention to the
immediate surroundings when parking and
maneuvering. This includes the area behind,
in front of, and beside the vehicle. Otherwise
you could endanger yourself and/or others.
GWARNING
The rear view camera will not function or will
not fully function if:
R the tailgate is open
R it is raining or snowing strongly or if it is
foggy
R it is night or if you are parking/
maneuvering your vehicle in a very dark
area
R a very bright white light is affecting the
camera
R the immediate vicinity is illuminated with
fluorescent light (the display can flicker)
R temperature changes abruptly, for example
if you drive out of the cold into a heated
garage (condensation on the lens)
R the camera lens is dirty or covered
R the rear of your vehicle is damaged
In this case, have the position and the
setting of the camera checked at a
specialist workshop. Mercedes-Benz
recommends that you consult a Mercedes-
Benz Center for this purpose.
Do not use the rear view camera in these
situations. You could otherwise injure
yourself and other people and/or cause
damage - including damage to your vehicle -
while parking/maneuvering.
Activating the rear view cameraXMake sure that the SmartKey is in position
2 in the ignition lock.XMake sure that the "rear view camera"
function is selected in COMAND (see the
separate operating instructions for
COMAND).XEngage reverse gear.
The area behind the vehicle is shown in the
COMAND display with guide lines.
Guide lines in the COMAND display
GWARNING
Use of rear view camera can be dangerous if
you are color-blind or have impaired color
vision.
Only use rear view camera if you can see and
distinguish all colored guidelines shown by
rear view camera on the COMAND system
display.
GWARNING
Please note that objects that do not touch the
ground may appear to be further away than
they actually are, for example:
R the bumper of a vehicle parked behind you
R the trailer drawbar
R the ball coupling of a trailer tow hitch
R the rear end of a truck
R a slanted post
In such cases, you should not use the guide
lines to judge the distance. You may misjudge
the distance, which increases the risk of
impacting the objects.
Even if the object you approach is directly on
the ground, do not approach the object any
closer than the red guide line.
188Driving systemsDriving and parking

Information in the COMAND display (example)
Guide lines ; and = show the approximate
distance to the rear area. Yellow guide
line ; indicates a distance of approximately
3 ft (1 m) and red guide line = indicates a
distance of approximately 10 in (0.25 m). The
distances only apply to objects that are at
ground level. Blue guide lines : depict the
width required for the vehicle. They are used
to align the vehicle with the edge of the road,
e.g. the curb.
Blind Spot Assist
Important safety notes
Blind Spot Assist uses a radar sensor system
to monitor the areas on both sides of your
vehicle. It begins to work at speeds of
approximately 20 mph (30 km/h). A warning
display in the exterior mirrors draws your
attention to detected vehicles in the
monitored area. If you then indicate a turn
towards that side before changing lanes, you
will also receive visual and audible collision
warnings. The Blind Spot Assist monitoring
system uses sensors in the rear bumper.
GWARNING
Blind Spot Assist is only an aid designed to
assist driving. It may fail to detect some
vehicles and is no substitute for attentive
driving.
Blind Spot Assist cannot detect road and
traffic conditions. It may fail to detect narrow
vehicles, such as motorcycles or bicycles, or
may only detect them too late.
Monitoring may be affected by dirty sensors,
strong spray or poor visibility caused by snow,
rain or mist, for example. In this case, vehicles
are detected late or not at all.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
i USA only:
This device has been approved by the FCC
as a “Vehicular Radar System”. The radar
sensor is intended for use in an automotive
radar system only. Removal, tampering, or
altering of the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
For Blind Spot Assist to assist you when
driving, the radar sensor system must be
activated ( Y page 208) and operational.
Monitoring range of the sensors
Blind Spot Assist monitors the area shown in
the figure up to 10 ft (3 m) behind and
immediately adjacent to your vehicle.
Driving systems189Driving and parkingZ

GWARNING
Blind Spot Assist monitors certain areas in the
immediate vicinity of your vehicle. Vehicles
that approach and drive past at high speeds
are not detected. There is no display and no
warning.
If the lanes are very wide, it may not be
possible to monitor the complete width of the
neighboring lane. For this reason, vehicles in
the next lane may not be detected, especially
if they are driving in a staggered formation.
This may be the case if vehicles are driving at
that edge of their lane which is furthest away
from your vehicle.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may
be indicated, especially if the vehicles are not
driving in the middle of their lane. This may
be the case if the vehicles are driving on the
inner side of their lane.
Due to the nature of the system:
R warnings may be issued in error when
driving close to crash barriers or similar
solid lane borders.
R warnings may be interrupted when driving
alongside particularly long vehicles, for
example trucks, for a prolonged time.
The two sensors for Blind Spot Assist are
integrated into the sides of the rear bumper.
Make sure that the bumper is free from dirt,
ice or slush around the sensors. The radar
sensors must not be covered, for example by
bicycle racks or overhanging cargo. Following
a severe impact or in the event of damage to
the bumpers, have the function of the radar
sensors checked at a qualified specialist
workshop, such as an authorized Mercedes-
Benz Center. Blind Spot Assist may otherwise
not work properly.
Indicator and warning display:Yellow indicator lamp/red warning lamp
When Blind Spot Assist is activated, indicator
lamp : lights up yellow in the exterior
mirrors up to a vehicle speed of 20 mph
(30 km/h). When the vehicle speed exceeds
20 mph (30 km/h), the indicator lamp goes
out and Blind Spot Assist is ready for use.
When your speed exceeds approximately
20 mph (30 km/h), warning lamp : lights up
red on the corresponding side whenever a
vehicle is detected in the blind spot
monitoring range. This warning is always
given when a vehicle enters the blind spot
monitoring range from behind or from the
190Driving systemsDriving and parking

side. When you are passing another vehicle,
the warning is emitted only if the difference
in speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if the
reverse gear is engaged. In this event, Blind
Spot Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.GWARNING
Blind Spot Assist is not active at speeds under
approximately 20 mph (30 km/h). The
indicator lamps in the exterior mirrors are
yellow. Vehicles in the monitoring range are
then not indicated.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the turn
signal, a double warning tone sounds. Red
warning lamp : flashes. If the turn signal
remains on, detected vehicles are indicated
by the flashing of red warning lamp :. There
are no further warning tones.
Switching on Blind Spot Assist
XMake sure that the radar sensor system
( Y page 208) and Blind Spot Assist
( Y page 210) are activated in the on-board
computer.XTurn the SmartKey to position 2 in the
ignition lock.
Warning lamps : light up red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.
Trailer towing
When you attach a trailer, make sure you have
correctly established the electrical
connection. This can be accomplished by
checking the trailer lighting. In this event,
Blind Spot Assist is deactivated. The indicator
lamp in the exterior mirrors lights up yellow
and the Blind Spot Assist Currently
Unavailable See Operator's Manual
message appears in the multifunction
display.
i You can deactivate the indicator lamps in
the exterior mirrors.
To do so, switch off Blind Spot Assist when:
R the SmartKey is in position 2 in the
ignition lock.
R the engine is not running.
R the electrical connection to the trailer
has been established.
Trailer towing
Notes on towing a trailer
Important safety notes
GWARNING
When towing a trailer, incorrect equipment
and driving style could cause you to lose
control of the vehicle.
Towing incorrectly or not observing this
Operator's Manual could lead to damage to
the vehicle and/or serious injuries. Observe
the following guidelines to ensure safe trailer
towing.
Contact a Mercedes-Benz Center if you need
further explanation of the information
contained in this Operator's Manual.
General information
R Only install an approved trailer coupling on
your vehicle.
Further information on availability and on
installation is available from any authorized
Mercedes-Benz Center.
R The bumpers of your vehicle are not
suitable for installing detachable trailer
couplings.
Trailer towing191Driving and parkingZ

Useful information ............................198
Important safety notes ....................198
Displays and operation ....................198
Menus and submenus ......................201
Display messages ............................. 213
Warning and indicator lamps in the
instrument cluster ............................238197On-board computer and displays