sensor MERCEDES-BENZ R-Class 2011 W251 Owner's Guide

Guide lines ; and = show the approximate
distance from the rear of the vehicle. 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 distance only applies to
objects at ground level. Blue line : depicts
the width required for the vehicle. It is used
to align the vehicle with the edge of the road,
e.g. the curb.
Blind Spot Assist
Important safety guidelines
Blind Spot Assist uses a radar sensor system
to monitor the areas on both sides of your
vehicle. It is active at speeds above
approximately 20 mph (30 km/h). A warning
display in the exterior mirrors draws your
attention to vehicles in the monitored area. If
you then indicate a turn towards that side
before changing lane, you will also receive
visual and audible collision warnings. For this
purpose, Blind Spot Assist 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.
iUSA 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. Removing, tampering
with, or altering 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
switched on (Y page 208) and operational.
Monitoring range of the sensors
Blind Spot Assist monitors the area up to 10 ft
(3 m) behind your vehicle and directly next to
your vehicle as shown in the diagram.
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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, the system may be
unable to distinguish the neighboring lane
from the one beyond it. For this reason, the
system may indicate vehicles in the farther
lane, especially if the vehicles are driving in a
staggered formation in different lanes. In
particular, this may be the case if the vehicles
are driving at that edge of their lane which is
nearest your vehicle.
Due to the nature of the system:
R warnings may be issued unnecessarily
when driving close to crash barriers or
similar solid lane borders.
R the warning may be interrupted when
traveling next to long vehicles for extended
periods.
The two sensors for Blind Spot Assist are
integrated into the sides of the rear bumper.
Make sure that the bumper is free of dirt, ice
or slush around the sensors. For example, the
radar sensors must not be covered by bicycle
racks or overhanging loads. In the event of a
severe impact or damage to the bumpers,
have the function of the radar sensors
checked at a qualified specialist workshop,
e.g. an authorized Mercedes-Benz Center.
Blind Spot Assist may otherwise not work
properly.
Information and warning display:Yellow indicator lamp/red warning lamp
If Blind Spot Assist is switched on, indicator
lamps : in the exterior mirrors light up
yellow up to a speed of 20 mph (30 km/h). At
speeds above 20 mph (30 km/h), the
indicator lamp goes out and Blind Spot Assist
is operational.
If a vehicle is detected within the monitoring
range of Blind Spot Assist at speeds above
20 mph (30 km/h), warning lamp : on the
corresponding side lights up red. This warning
is always emitted when a vehicle enters the
blind spot monitoring range from behind or
from the side. When you overtake a vehicle,
the warning only occurs 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
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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 key 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.
Towing a trailer
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 lights up yellow in the exterior mirrors
and the message: Blind Spot Assist
Currently Unavailable See
Operator's Manual appears in the
multifunction display.
i The indicator lamps in the exterior mirrors
can be switched off.
To do this, you must deactivate Blind Spot
Assist when:
R the key is in position 2 in the ignition
lock.
R the engine is not running.
R the electrical connection to the trailer
has been established.
Towing a trailer
Notes on towing a trailer
Important safety instructions
GWarning!
Failure to use proper equipment and driving
technique can result in a loss of vehicle
control when towing a trailer.
Improper towing or failure to follow the
instructions in this manual can result in
vehicle damage and/or serious personal
injury. Follow the guidelines below carefully
to assure safe trailer operation.
Contact an authorized Mercedes-Benz Center
should you require an explanation of
information contained in this 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.
R Do not install hired trailer couplings or
other detachable trailer couplings on the
bumpers of your vehicle.
R To reduce the risk of damage to the ball
coupling, remove it from the ball coupling
recess when not in use.
Coupling up a trailer
GWarning!
Vehicles with AIRMATIC: 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.
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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.
Activating/deactivating the interior
lighting delayed switch-off
When you activate the Interior Lighting
Delayed Shut-off function and remove the
SmartKey from the ignition lock, the interior
lighting remains on for 10 seconds.
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 Interior
Lighting Delayed Shut-off .XPress the W or X button to activate
or deactivate the Interior Lighting
Delayed Shut-off function.XPress the &, V or U button to
select a different display.Vehicle
Activating/deactivating the automatic
locking feature
When you activate the Automatic Door
Locking function, your vehicle will be
centrally locked above a speed of
approximately 9 mph (15 km/h).
i Further information on the automatic
locking feature ( Y page 81).
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
Vehicle submenu.XPress & to select Automatic Door
Locking .XPress W or X to switch Automatic
Door Locking on or off.XPress the &, V or U button to
select a different display.
Activating/deactivating the radar sensor
system
If the radar sensor system is switched off,
Blind Spot Assist (Y page 191) is deactivated.
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.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
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2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.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
Vehicle submenu.XPress the & button to select Radar
Sensor (See Operator's Manual) .XPress the W or X button to activate
or deactivate the Radar Sensor (See
Operator's Manual) .XPress the &, V or U button to
select a different display.
Convenience
Activating/deactivating the EASY-
ENTRY/EXIT feature
You can use the Easy-entry Function to
activate or deactivate the easy-entry/exit
feature ( Y page 110).
GWarning
You must make sure no one can become
trapped or injured by the moving steering
wheel when the easy-entry/exit feature is
activated.
To stop steering wheel movement do one of
the following:
R Move steering wheel adjustment stalk.
R Press one of the memory position buttons.
R Press memory button M.
Do not leave children unattended in the
vehicle, or with access to an unlocked vehicle.
Children could open the driver's door and
unintentionally activate the easy-entry/exit
feature, which could result in an accident
and/or serious personal injury.
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
Comfort submenu.XPress & to select the Easy-entry
Function function.XPress the W or X to activate or
deactivate the Easy-entry Function
function.XPress the &, V or U button to
select a different display.
Switching the belt adjustment on/off
Further information on belt adjustment
( Y page 56).
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
Comfort submenu.XPress the & button to select Belt
Adjustment .XPress the W or X button to activate
or deactivate Belt Adjustment .XPress the &, V or U button to
select a different display.
Switching the fold in mirrors when
locking function on/off
When you activate the Fold In Mirrors
When Locking function, the exterior mirrors
are folded in when the vehicle is locked. When
you switch on the ignition, the exterior
mirrors fold out again.
If you have switched the function on and you
fold the exterior mirrors in using the button
on the door ( Y page 112), they will not fold
out automatically. The exterior mirrors can
then only be folded out using the button on
the door.
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Display messagesPossible causes/consequences and M Solutionsb
AUTO Light
InoperativeThe light sensor is faulty. The low-beam headlamps are switched
on.XUSA only: switch off daytime driving lights in the on-board
computer ( Y page 206).XSwitch the lights on and off using the light switch.XVisit a qualified specialist workshop.b
Switch Off LightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to $ or c .
or
XIf the rear fog lamp is switched on: press the light switch in to
the stop.
Engine
Display messagesPossible causes/consequences and M Solutions+
Top Up Coolant See
Operator's ManualThe coolant level is too low.XAdd coolant, observing the warning notes before doing so
( Y page 281).XIf coolant needs adding more often than usual, have the engine
coolant system checked at a qualified specialist workshop.GWarning
Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may burn
if it comes into contact with hot engine parts. You could be seriously burned.
! The coolant level is too low. Avoid making long journeys with too little coolant in the cooling
system. The engine will otherwise be damaged.
The display messages and the corresponding symbol that indicate that the coolant level is
too low must not be ignored.
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Display messagesPossible causes/consequences and M SolutionsBlind 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 287).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.Cruise Control
--- mph A condition for activating cruise control has not been met.
You wanted to save a speed of less than 20 mph (30 km/h).XIf the situation allows, drive faster than 20 mph (30 km/h) and
save the speed.XCheck the activation conditions for cruise control
( Y page 173).DISTRONIC
--- MPH An activation condition for DISTRONIC is not fulfilled.XIf the situation allows, drive faster than 20 mph (30 km/h) and
save the speed.XCheck activation conditions for DISTRONIC ( Y page 175).Display messages229On-board computer and displaysBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 229Z

Display messagesPossible causes/consequences and M SolutionsDISTRONIC
OverrideDISTRONIC is no longer controlling the speed of the vehicle.XTake your foot off the accelerator pedal.DISTRONIC
InoperativeDISTRONIC is faulty or the display has failed.XVisit a qualified specialist workshop.DISTRONIC
Currently
Unavailable See
Operator's ManualDISTRONIC is deactivated and is temporarily inoperative if:
R the DISTRONIC cover in the radiator grill is dirty.
R its function is impaired due to heavy rain, snow or fog.
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 radar sensor system has not detected any vehicles or
stationary objects, e.g. traffic signs, for a long time.
R the system is outside the operating temperature range.
DISTRONIC becomes available 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 system is within the operating temperature range.
If the display message continues to be displayed:XClean the DISTRONIC cover in the radiator grill ( Y page 287).XRestart the engine.GWarning
DISTRONIC cannot take weather conditions into account. Switch off DISTRONIC or do not turn
it on if the sensor is dirty or visibility is diminished as a result of snow, rain or fog. The distance
control may be impaired even before the system is able to detect a dirty sensor. The DISTRONIC
Currently Unavailable See Operator’s Manual message will be displayed in the
multifunction display and DISTRONIC will be turned off.
Tires
GWarning
Do not drive with a flat tire. A flat tire affects the ability to steer or brake the vehicle. You may
lose control of the vehicle. Continued driving with a flat tire will cause excessive heat build-up
and possibly a fire.
GWarning
Follow recommended tire inflation pressures.
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Do not underinflate tires. Underinflated tires wear excessively and/or unevenly, adversely affect
handling and fuel economy, and are more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can adversely affect handling and ride comfort, wear
unevenly, increase stopping distance, and result in sudden deflation (blowout) because they are
more likely to become punctured or damaged by road debris, potholes etc.Display messagesPossible causes/consequences and M SolutionsTire Pressure
Check TiresGRisk of accident
The tire pressure loss warning system has detected a significant
loss in pressure.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XCheck the tires and, if necessary, change the wheel
( Y page 336).XCheck the tire pressures and, if necessary, set to the correct
tire pressure.XRestart the tire pressure loss warning system when the tire
pressure is correct ( Y page 325).Check tires,
then restart Run
Flat IndicatorA display message for the tire pressure loss warning system was
shown.XSet the correct tire pressure in all four tires.XRestart the tire pressure loss warning system ( Y page 325).Run Flat Indicator
InoperativeThe tire pressure loss warning system is faulty.XVisit a qualified specialist workshop.Tire pressure
displayed after
driving for a few
minutesThe tire pressure monitor is measuring the tire pressure.XDrive on.
The tire pressures appear in the multifunction display after you
have been driving for a few minutes.Tire Pressure
Monitor
InoperativeThe TPMS is faulty.XVisit a qualified specialist workshop.Tire Pressure
Monitor
Inoperative No
Wheel SensorsThe wheels mounted do not have a suitable tire pressure sensor.
The tire pressure monitor is deactivated.XMount wheels with suitable tire pressure sensors.
The TPMS is activated automatically after driving for a few
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Display messagesPossible causes/consequences and M SolutionsCheck
Tire(s)GRisk of accident
The tire pressure in one or more tires has dropped significantly.
The wheel position is displayed in the multifunction display.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XCorrect the tire pressure ( Y page 327).XIf necessary, change the wheel ( Y page 336).Caution:
Tire DefectGRisk of accident
The tire pressure in one or more tires has dropped suddenly. The
wheel position is displayed in the multifunction display.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change the wheel ( Y page 336).Tire pressure(s)
Please CorrectThe tire pressure is insufficient in at least one of the tires or the
tire pressure difference between the wheels is too great. The
wheel position is displayed in the multifunction display.XCheck the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 327).XRestart the tire pressure monitor ( Y page 329).Tire Pressure
Monitor
Wheel Sensor
MissingThere is no signal from the tire pressure sensor of one or several
wheels. The pressure of the affected tire is not displayed in the
multifunction display.XHave the faulty tire pressure sensor replaced at a qualified
specialist workshop.Tire Pressure
Monitor
Currently
UnavailableDue to a source of radio interference no signals can be received
from the wheel sensors. The tire pressure monitor is temporarily
malfunctioning.XDrive on.
The TPMS restarts automatically as soon as the problem has
been solved.h
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 the wheel ( Y page 336).232Display messagesOn-board computer and displays
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