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XCleaning inside of windshield: Use a soft,
non-scratching cloth ( Y page 263).
Blind Spot Assist
The Blind Spot Assist uses radar sensors to
monitor the area on both sides of your
vehicle. It will assist you when you change
lanes driving at speeds of above 20 mph
(30 km/h). A red warning lamp will come on
in the exterior rear view mirror as soon as
another vehicle is detected. If you then
activate the corresponding turn signals to
change lanes, the red warning lamp flashes
and warning sounds (collision warning). The
Blind Spot Assist operates using sensors in
the rear bumper.
GWarning!
The Blind Spot Assist is only a driving aid and
may not detect all vehicles.
The Blind Spot Assist may not be able to
detect narrow vehicles such as motorcycles
or bicycles, or it may not detect them until it
is too late.
The monitoring function may be impaired if
your sensors are dirty, subject to heavy spray,
or if visibility is poor due to e.g. snow, rain, or
fog. This can result in vehicles not being
detected or being detected too late.
The Blind Spot Assist cannot detect road,
traffic and weather conditions.
It is the driver’s responsibility at all times to
be attentive to road, weather and traffic
conditions and to provide the steering,
braking and other driving inputs necessary to
retain control of the vehicle. Failure to do so
could result in recognizing dangers too late,
possibly resulting in an accident and serious
injury to yourself and others.
In order for the Blind Spot Assist to function,
the radar sensors must be switched on and
operational.
When traveling in Canada in a vehicle not
registered in Canada, you must switch off the
radar sensor system ( Y page 144). Canadian
law does not permit the use of the radar
sensor system for vehicles from outside of
Canada. When you switch off the radar sensor
system, the following functions are
deactivated:
R Blind Spot Assist
R BAS PLUS ( Y page 63)
R PRE-SAFE ®
Brake ( Y page 69)
R DISTRONIC PLUS ( Y page 149)
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
2. this device must accept any interference received, including
interference that may cause undesired
operation of the device.
Removal, tampering, or altering of the
device will void any warranties, and is not
permitted. 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.
Sensor monitoring range
The Blind Spot Assist is able to monitor a
range up to 10 ft (3 m) to the rear and both
sides of the vehicle.
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GWarning!
The Blind Spot Assist monitors certain areas
in the immediate vicinity of your vehicle.
Vehicles approaching and passing at speeds
that exceed the speed of your vehicle
significantly will not be detected. There will be
no warning display and no audible warning.
When driving in a very wide lane, the sensors
may not be able to cover the entire width of
the neighboring lane. Vehicles driving on the
outside of the neighboring lane may not be
detected.
It is the driver’s responsibility at all times to
be attentive to road, weather and traffic
conditions and to provide the steering,
braking and other driving inputs necessary to
retain control of the vehicle. Failure to do so
could result in recognizing dangers too late,
possibly resulting in an accident and serious
injury to yourself and others.
When driving in a very narrow lane, the
sensors may detect and display vehicles in the
second lane over. This will be the case if there
are vehicles driving on the inside edge of their
lane.
The system may issue causeless warnings in
the area of guardrails or similar structural
boundaries.
The two Blind Spot Assist sensors are built
into the rear bumper. Make sure that the area
of the bumper around the sensors is free of
dirt, ice and snow. The radar sensors must not
be obstructed, for example, by bicycle
carriers or overhanging luggage.
! In the event of a significant impact or
damage affecting the bumpers, have the
radar sensors checked by a qualified
specialist workshop such as a Mercedes-
Benz Center. Failure to do this can result in
Blind Spot Assist not functioning correctly.
Indicator and warning lamps
Exterior rear view mirror, driver’s side
XMake sure that the radar sensors
(Y page 144) and Blind Spot Assist
(Y page 138) are switched on.
XSwitch on the ignition.
Red warning lamps : in the exterior rear
view mirrors come on.
XStart the engine.
Yellow indicator lamps : in the exterior
rear view mirrors come on up to a speed of
20 mph (30 km/h).
Above a speed of 20 mph (30 km/h), yellow
indicator lamps : go out and the Blind Spot
Assist is active. If the Blind Spot Assist
detects a vehicle in its range, red warning
lamp : on the corresponding side of the
vehicle comes on. The warning is issued each
time a vehicle enters the area monitored by
the Blind Spot Assist from behind or from the
side. When you pass another vehicle, the
warning is issued only when the speed
differential is less than 7 mph (12 km/h).
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When you shift the automatic transmission in
reverse gear R, yellow indicator lamps : in
the exterior rear view mirrors goes out after
approximately 3 seconds. The Blind Spot
Assist is then not active.
The brightness of indicator lamps/warning
lamps : is controlled automatically
depending on the brightness of the ambient
light.
GWarning!
The Blind Spot Assist is not active at speeds
below approximately 20 mph (30 km/h). The
yellow indicator lamps in the exterior rear
view mirrors are illuminated. You will not be
alerted to the presence of vehicles in the
monitored area at these speeds.
It is the driver’s responsibility at all times to
be attentive to road, weather and traffic
conditions and to provide the steering,
braking and other driving inputs necessary to
retain control of the vehicle. Failure to do so
could result in recognizing dangers too late,
possibly resulting in an accident and serious
injury to yourself and others.
Collision warning
If a vehicle is detected in the Blind Spot Assist
range and you activate the turn signal, a two-
tone warning will sound once. Red warning
lamp : on the corresponding side of the
vehicle will flash.
GWarning!
Do not change lanes or make turns, while red
warning lamp : is flashing. Doing so could
result in an accident and serious injury to
yourself and others.
XRemain on the lane that you are currently
on until traffic conditions permit to change.
If the turn signal remains on, red warning
lamp : will flash to indicate that vehicles
have been detected. No further audible
warnings will sound.
Lane Keeping Assist
The Lane Keeping Assist supports you at a
vehicle speed of above 40 mph when you
have set the display unit to miles in the
Display Unit Speed-/Odometer: menu in
the control system (Y page 141). When you
have set the display unit to km, the system
supports you at a vehicle speed of above
60 km/h. When the Lane Keeping Assist
detects lane markings, the system is
designed to alert you in case you leave your
lane unintentionally. A warning is usually
issued when a front wheel is on the lane
marking. An interval vibration in the steering
wheel that lasts for up to 1.5 seconds will
then alert you.
The Lane Keeping Assist monitors the area in
front of your vehicle via camera :.
The system can distinguish various
conditions in order to alert you early enough
and to avoid unnecessary warnings when
crossing lane markings.
The warning is issued sooner when
Rcutting a curve on the outside of the turn
Rdriving on very wide lanes such as highway
lanes
Rthe system recognizes dividing lines
because crossing them is often crucial due
to soft shoulders or guardrails behind for
example
The warning is issued later however when
Rdriving on narrow lanes
Rcutting a curve on the inside of the turn
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The system does not issue a warning when
Rsteering, braking, or accelerating in a
clearly active manner, e.g. when changing
lanes, passing, exiting a highway
Rcutting a narrow curve
Rmaking a very sharp turn
Ra driving safety system such as the ABS,
the BAS, or the ESC has been activated
When setting the turn signal in either
direction, the warning will be suppressed. The
system will issue a warning if a turn signal has
been on for an extended period of time.
GWarning!
The Lane Keeping Assist does not keep the
vehicle in the lane. The Lane Keeping Assist
is only an aid to the driver and may not always
recognize lane markings properly or fail to
recognize them at all.
The system may be impaired or unavailable
when
Rvisibility is poor, e.g. due to snow, rain, fog,
or heavy spray
Roncoming traffic, sun glare or reflection
from other vehicles
Rthe camera area of the windshield is dirty,
foggy, or otherwise obstructed
Rlane markings are not present
Rlane markings are worn, dark, or covered
e.g. by snow or dirt
Rthe distance to the preceding vehicle is too
short
Rwhen lane markings are ambiguous, for
example in road work sections
Rlane markings change rapidly, e.g. on
highway exits or turn-off lanes
Rlanes are narrow and winding
The Lane Keeping Assist cannot take road and
traffic conditions into account. It is the
driver’s responsibility at all times to be
attentive to road, weather and traffic
conditions and to provide the steering,
braking and other driving inputs necessary to
retain control of the vehicle. Failure to do so
could result in recognizing dangers too late,
possibly resulting in an accident and serious
injury to yourself and others.
Switching on or off
Example illustration
XSwitch on or off the Lane Keeping Assist via
the control system (Y page 138).
Lane Keeping Assist indicator : appears
in the multifunction display.
ATTENTION ASSIST
The ATTENTION ASSIST supports you during
long, monotonous rides, e.g. on freeways and
highways. The ATTENTION ASSIST is active at
a vehicle speed of between 50 mph
(80 km/h) and 112 mph (180 km/h). Always
obey applicable speed limits. The
ATTENTION ASSIST suggests to take a rest
when recognizing fatigue or increasing
inattentiveness of the driver.
GWarning!
The ATTENTION ASSIST is only an aid to the
driver. It might not recognize fatigue or
increasing inattentiveness in time or fail to
recognize them at all. The system cannot
substitute a rested and attentive driver.
Fatigue can cause you to recognize dangers
too late, to misjudge potential dangers, or to
react slower. Therefore, make sure to be
rested before and during your trip. Take rests
early enough and regularly, especially during
long trips. Failure to do so could cause you to
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recognize dangers too late which could result
in an accident and serious injury to you and/
or others.
The ATTENTION ASSIST interprets your
fatigue or increasing inattentiveness
considering the following criteria:
Rthe individual driving style, for example the
way you steer
Rthe driving conditions such as time of day
and duration of the ride
The ATTENTION ASSIST function is restricted
and warnings will be delayed or not issued at
all when
Rroad conditions are bad, e.g. heavy bumps
or potholes
Rcrosswinds are strong
Rdriving in a sporty manner with high speed
in curves or rapid acceleration
Rdriving slower than 50 mph (80 km/h) or
faster than 112 mph (180 km/h) most of
the time
Roperating the COMAND or making phone
calls via COMAND
Rchanging lanes or varying the vehicle
speed, i.e. you intervene actively
Warnings and displays in the
multifunction display
Example illustration
XSwitch on the ATTENTION ASSIST via the
control system (Y page 138).
ATTENTION ASSIST indicator : appears in
the multifunction display.
When the ATTENTION ASSIST is active, it will
warn you after 20 minutes of driving at the
earliest. An intermittent warning will then
sound twice and the message Attention
Assist: Time for a rest? appears in the
multifunction display.
XIf possible park your vehicle in a safe
location and take a rest.
XConfirm the message by pressing button
a on the multifunction steering wheel.
If you do not take a rest and the
ATTENTION ASSIST continues to recognize
fatigue or increasing inattentiveness, you will
be warned once more after 15 minutes at the
earliest.
During long trips, take regular and duly rests
that allow you to recover sufficiently.
The ATTENTION ASSIST will be reset and
restarts evaluating the degree of your fatigue
when
Ryou turn off the engine
Ryou release the seat belt and open the
driver’s door, e.g. during a rest or for a
driver change
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Climate control system
Overview of climate control system functions
Your vehicle is equipped with either of the following climate control systems:
Dual-zone automatic climate control
USA only
Canada only
3-zone automatic climate control
Canada only
The dual-zone automatic climate control
combines an automatic heating and
ventilation system with a cooling system.
You can adjust the dual-zone automatic
climate control separately for the driver’s
and passenger side.
The 3-zone automatic climate control
combines an automatic heating and
ventilation system with a cooling system.
You can adjust the 3-zone automatic climate
control separately for each zone in the
vehicle.
Rear climate control
Canada only
The rear climate control allows separate climate settings for the rear compartment.180Climate control systemControls in detail
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Control panels
Dual-zone automatic climate control
USA only
FunctionRecommendation/Notes:Air distribution and
air volume
(automatic mode)
iSwitch on the automatic mode. The
indicator lamp above button à comes
on.
(Y page 186);Front defrosteriKeep this setting selected only until the
windshield and the front door windows are
clear again.
(Y page 189)=ZONE-function on/
off
(Y page 191)?Air recirculationiOnly use this function for a short time,
e.g. in a tunnel. Otherwise, the windows
can fog up due to lack of fresh air.
(Y page 190)AMAX COOL function
on/off
(Y page 190)BA/C cooling on/offiSwitch on/off the air conditioning.(Y page 185)CRear window
defroster
(Y page 191)DClimate control on/
off
iSwitch on/off the climate control
system.
(Y page 185)ETemperature
control, passenger
side
iSet the temperature to 72‡ (22†).(Y page 186)FAir distribution(Y page 189)GAir volume(Y page 189)Climate control system181Controls in detail212_AKB; 2; 41, en-USd2ureepe,Version: 2.11.8.12009-07-17T09:14:21+02:00 - Seite 181Z
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FunctionRecommendation/NotesHTemperature
control, driver’s side
iSet the temperature to 72‡ (22†).(Y page 186)IDisplay
Canada only
FunctionRecommendation/Notes:Air recirculationiOnly use this function for a short time,
e.g. in a tunnel. Otherwise, the windows
can fog up due to lack of fresh air.
(Y page 190);Front defrosteriKeep this setting selected only until the
windshield and the front door windows are
clear again.
(Y page 189)=ZONE-function on/
off
(Y page 191)?DisplayAAir distribution and
air volume
(automatic mode)
iSwitch on the automatic mode. The
indicator lamp above button à comes
on.
(Y page 186)BA/C cooling on/offiSwitch on/off the air conditioning.(Y page 185)CRear window
defroster
(Y page 191)DClimate control on/
off
iSwitch on/off the climate control
system.
(Y page 185)ETemperature
control, passenger
side
iSet the temperature to 72‡ (22†).(Y page 186)FAir distribution(Y page 189)182Climate control systemControls in detail
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