Mercedes-Benz 2009 S-Class Operator's Manual page 396

Controls in detail
Driving systems
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 Blind Spot Assist sensors are built into
the front and rear bumpers. Make sure that
the area of the bumpers 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.
394
Indicator and warning lamps
Exterior rear view mirror, driver's side
Yellow indicator lamp/red warning lamp
1
X
Make sure that the radar sensors
( Y page 253) and Blind Spot Assist
( Y page 251) are switched on.
X
Switch on the ignition.
Red warning lamps in the exterior rear
1
view mirrors come on.
X
Start the engine.
Yellow indicator lamps in the exterior
1
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
1
Assist is active. If the Blind Spot Assist
detects a vehicle in its range, red warning
lamp on the corresponding side of the
1
vehicle comes on.
When you shift the automatic transmission in
reverse gear R, yellow indicator lamps
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
1
depending on the brightness of the ambient
light.
G Warning!
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 and red warning
lamp on the corresponding side of the
1
in
1
vehicle will flash.