
the instrument cluster goes out. The 
_
indicator lamp in the multifunction display
remains lit.
X To deactivate:  move the combination
switch back to its normal position.
The _ indicator lamp in the instrument
cluster goes out. Headlamps fogged up on the inside
The headlamps may fog up on the inside if
there is high atmospheric humidity.
X Switch on the light and drive off.
The level of moisture diminishes,
depending 
on the length of the journey and
the weather conditions (humidity and
temperature).
If the level of moisture does not diminish:
X Have the headlamps checked at a qualified
specialist workshop. Interior lighting
Overview of interior lighting
Front overhead control panel
:
u To switch the rear interior lighting
on/off
; | To switch the automatic interior
lighting control on/off
= p To switch the right-hand front
reading lamp on/off ?
c To switch the front interior lighting
on/off
A p 
To switch the left-hand front reading
lamp on/off Rear-compartment overhead control panel
:
p To switch the right-hand reading
lamp on/off
; p 
To switch the left-hand reading lamp
on/off Interior lighting control
General notes In order to prevent the vehicle's battery from
discharging, 
the interior lighting functions are
automatically deactivated after some time
unless the SmartKey is in position 2 in the
ignition lock.
The color and brightness of the ambient
lighting may be set using the on-board
computer (Y page 239). 128
Interior lighting
Lights and windshield wipers     

Automatic interior lighting control
Front overhead control panel
:
u To switch the rear interior lighting
on/off
; | To switch the automatic interior
lighting control on/off
= p To switch the right-hand reading
lamp on/off
? c To switch the front interior lighting
on/off
A p To switch the left-hand reading lamp
on/off
X To activate/deactivate:  press the |
button.
When the automatic interior lighting
control 
is activated, the button is flush with
the overhead control panel.
The interior lighting automatically switches
on if you:
R unlock the vehicle
R open a door
R remove 
the SmartKey from the ignition lock
The interior light is activated for a short while
when the SmartKey is removed from the
ignition lock. You can activate this delayed
switch-off using the on-board computer
(Y page 240). Manual interior lighting control
Front overhead control panel
:
u To switch the rear interior lighting
on/off.
; | To switch the automatic interior
lighting control on/off
= p To switch the right-hand reading
lamp on/off
? c To switch the front interior lighting
on/off
A p 
To switch the left-hand reading lamp
on/off
X To switch the front interior lighting on/
off: press the c button.
X To switch the rear interior lighting on/
off: press the u button.
X To switch the reading lamps on/off:
press the p button. Crash-responsive emergency lighting
The 
 interior lighting is activated automatically
if the vehicle is involved in an accident.
X To switch off the crash-responsive 
emergency lighting:  press the hazard
warning lamp button.
or
X Lock and then unlock the vehicle using the
SmartKey. Interior lighting
129
Lights and windshield wipers Z     

Display when DISTRONIC PLUS is
deactivated
:
Vehicle in front, if detected
; Distance indicator, current distance to
the vehicle in front
= Specified minimum distance to the
vehicle in front; adjustable
? Own vehicle
X Select the  Distance Display function
using the on-board computer
(Y page 236).
Display when DISTRONIC PLUS is
activated :
DISTRONIC PLUS activated
; Own vehicle
= Specified minimum distance to the
vehicle in front; adjustable
? Vehicle in front, if detected
X Select the  Distance Display function
using the on-board computer
(Y page 236). i
You will see the stored speed for about
five 
seconds when you activate DISTRONIC
PLUS.
Deactivating DISTRONIC PLUS G
WARNING
DISTRONIC PLUS is deactivated and releases
the brakes if the vehicle is slowed down to a
speed 
below 20 mph (30km/h) by the system,
provided that DISTRONIC PLUS does not
detect a vehicle directly in front. At this point,
the driver must apply the brakes in order to
slow down further and bring the vehicle to a
standstill. There are several ways to deactivate
DISTRONIC PLUS:
X
Briefly press the cruise control lever
forwards  :.
or
X Brake, unless the vehicle is stationary.
When you deactivate DISTRONIC PLUS, you
will see the  DISTRONIC PLUS Off message
in 
the multifunction display for approximately
five seconds.
i The last speed stored remains stored until
you switch off the engine.
DISTRONIC PLUS is automatically
deactivated if:
R you engage the parking brake.
R you are driving slower than 15 mph
(25 km/h) and there is no vehicle in front,194
Driving systems
Driving and parking       

Indicator and warning display
G
WARNING
Blind Spot Assist is not active at speeds below
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. :
Yellow indicator lamp/red warning lamp
When Blind Spot Assist is activated, indicator
lamp  : in the exterior mirrors lights up
yellow 
at speeds of up to 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 (30km/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 (12km/h).
The yellow indicator lamp goes out if 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. Collision warning
If 
a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the
corresponding 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
X Make sure that the radar sensor system
(Y page 241) and Blind Spot Assist
(Y page 
237) are activated in the on-board
computer.
X Turn 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.
Lane Keeping Assist Important safety notes
G
WARNING
Lane Keeping Assist does not keep your
vehicle in its lane. It is only an aid and may
detect the lane markings on the road
incorrectly or not at all.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to
insufficient illumination of the road, or due
to snow, rain, fog or spray.
R there is glare, e.g. from oncoming traffic,
the sun, or reflection from other vehicles.
R the windshield is dirty, fogged up or
covered, for instance by a sticker, in the
vicinity of the camera.
R several 
or no lane markings for a single lane
are present.
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow.
R the distance to the vehicle in front is too
small and the lane markings thus cannot be
detected.216
Driving systems
Driving and parking   

R
the lane markings on the road are unclear,
e.g. near roadworks.
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge.
R the road is narrow and winding.
Lane Keeping Assist cannot detect road and
traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, braking in good time, and
steering correctly. Always adapt your driving
style to suit the prevailing road and weather
conditions. 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.
General notes Lane Keeping Assist monitors the area in
front of your vehicle by means of a
camera 
: 
at the top of the windshield. Lane
Keeping Assist detects lane markings on the
road and warns you before you leave your
lane unintentionally.
If you have selected  km as the display unit in
the Display Unit Speed-/
Odometer(Y page 238) function in the on-
board computer, Lane Keeping Assist assists
you at speeds above 60 km/h. If  miles is
selected as the display unit, the assistance
range starts at 40 mph.
A warning may be given if a front wheel
passes over a lane marking. It will warn you by means of intermittent vibration in the
steering wheel for up to 1.5 seconds.
Switching on Lane Keeping Assist
X
Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive(Y page 237).
Symbol  : appears in the multifunction
display.
If your speed exceeds 
40 mph (60 km/h)
and lane markings are detected,
symbol  : is highlighted. Lane Keeping
Assist is ready for use.
Standard
If  Standard 
is selected, no warning vibration
occurs if:
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, such as
ABS, BAS or ESP ®
.
Adaptive
If  Adaptive is selected, no warning vibration
occurs if:
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard.
R you steer actively, e.g. swerve to avoid an
obstacle or change lane quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when
necessary and in good time if you cross the Driving systems
217
Driving and parking Z     

If Active Blind Spot Assist detects a risk of a
lateral collision in the monitoring range, a
course-correcting 
brake application is carried
out. This is meant to assist you in avoiding a
collision.
If a course-correcting brake application
occurs, red warning lamp  : flashes in the
exterior mirror and a dual warning tone
sounds. The display shown in the illustration
also appears in the multifunction display.
The course-correcting brake application is
available in the speed range between
20 mph(30 km/h) and120 mph(200 km/h).
Either no braking application, or a course-
correcting brake application adapted to the
driving situation occurs, if:
R there are vehicles or obstacles, e.g. crash
barriers, located on both sides of your
vehicle.
R a vehicle approaches you too closely at the
side.
R you have adopted a sporty driving style with
high cornering speeds.
R you clearly brake or accelerate.
R a driving safety system intervenes, e.g.
ESP ®
 or PRE-SAFE ®
 Brake. R
ESP ®
 is switched off.
R a loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist
X Make sure that the radar sensor system
(Y page 241) and Active Blind Spot Assist
(Y page 
237) are activated in the on-board
computer.
X Turn the SmartKey to position  2 in the
ignition lock.
Warning lamps  : in the exterior mirrors
light up red for approximately
1.5 seconds
 and then turn yellow.
Active Lane Keeping Assist Important safety notes
G
WARNING
Active Lane Keeping Assist does not keep
your vehicle in its lane. It is only an aid and
may detect the lane markings on the road
incorrectly or not at all.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to
inadequate 
illumination of the road surface,
snow, rain, fog or spray.
R there is glare, e.g. from oncoming traffic,
the sun, or reflection from other vehicles.
R the windshield is dirty, fogged up or
covered, for instance by a sticker, in the
vicinity of the camera.
R several or no lane markings for a single lane
are present.
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow.
R the distance to the vehicle in front is too
small, and as a result the lane markings
cannot be recognized.
R the lane markings on the road are unclear,
e.g. near roadworks. Driving systems
221
Driving and parking
Z     

R
the lane markings change quickly, e.g.
branch off, cross or merge.
R the road is narrow and winding.
Active Lane Keeping Assist cannot detect
road and traffic conditions. It is not a
substitute for attentive driving. You are
responsible 
for the vehicle's speed, braking in
good time and steering correctly. Always
adapt your driving style to suit the prevailing
road and weather conditions. 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.
General notes Active Lane Keeping Assist monitors the area
in front of your vehicle by means of a
camera 
: 
at the top of the windshield. Active
Lane Keeping Assist detects lane markings on
the road and warns you before you leave your
lane unintentionally. If you do not react to the
warning, a lane-correcting application of the
brakes can bring the vehicle back into the
original lane.
In the  Display Unit Speed-/Odometer:
on-board computer function (Y page 238), if
you select the  km display unit, Active Lane-
Keeping Assist is activated at a speed of
60 km/h. If the  Miles display unit is selected,
the assistance range begins at 40 mph.
Warning vibration in the steering wheel
A warning may be given if a front wheel
passes over a lane marking. It will warn you by means of intermittent vibration in the
steering wheel for up to 1.5 seconds.
In order that you are warned only when
necessary and in good time if you cross the
lane marking, the system recognizes certain
conditions and warns you accordingly.
The warning vibration occurs earlier if:
R
you approach the outer lane marking on a
bend.
R the road has very wide lanes, e.g. a
freeway.
R the 
system recognizes solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.
Lane-correcting brake application G
WARNING
Active Lane Keeping Assist does not keep
your vehicle in its lane. It is only an aid
designed 
to assist driving. It is not a substitute
for attentive driving. In some cases, the lane-
correcting brake application is not sufficient
to bring your vehicle back to the original lane.
In such cases, you must steer the vehicle
yourself to ensure that it does not leave the
lane.
Active Lane Keeping Assist does not detect
road and traffic conditions. Always make sure
that there is sufficient distance to the side for
other traffic or obstacles. In rare cases,
unclear markings or particular structures on
the roadway can be recognized as solid lane
markings. An inappropriate brake application,
e.g. after intentionally driving over a solid lane
marking, may be interrupted at any time by
steering slightly in the opposite direction.
Active Lane Keeping Assist cannot take
weather conditions into account.
You are responsible for the driving at
appropriate speeds, braking in good time, and
steering correctly. Always adapt your driving
style to suit the prevailing road and weather
conditions. Always pay attention to traffic
conditions and your surroundings. Otherwise, 222
Driving systems
Driving and parking   

you may fail to recognize dangers in time,
cause an accident and injure yourself and
others.
If a lane-correcting brake application occurs,
the display shown in the illustration appears
in the multifunction display.
If you leave your lane under certain
circumstances the vehicle will brake briefly
on one side. This is meant to assist you in
bringing 
the vehicle back to the original lane.
This function is available in the range between
40 mph and 120 mph (60 km/h and
200 km/h).
A lane-correcting brake application can only
be made after driving over a solid,
recognizable lane marking. Before this, a
warning must be given by means of
intermittent vibration in the steering wheel.
In addition, a lane with lane markings on both
sides must be recognized. The brake
application also slightly reduces vehicle
speed.
i A further lane-correcting brake
application can only occur after your
vehicle has returned to the original lane.
No lane-correcting brake application occurs
if:
R you clearly and actively steer, brake or
accelerate.
R you cut the corner on a sharp bend.
R you have switched on the turn signals.
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
 Brake or Active Blind
Spot Assist.
R you have adopted a sporty driving style with
high cornering speeds or high rates of
acceleration. R
ESP ®
 is switched off.
R the transmission is not in position  D.
R a 
loss of tire pressure or a defective tire has
been detected and displayed.
Active Lane Keeping Assist does not detect
traffic situations or road users. An
inappropriate brake application may be
interrupted at any time if you:
R steer slightly in the opposite direction.
R use a turn signal.
R clearly brake or accelerate.
A lane-correcting brake application is
interrupted automatically if:
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
 Brake or Active Blind
Spot Assist.
R lane markings can no longer be recognized.
Switching on Active Lane Keeping Assist X
Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive(Y page 237).
Symbol  : appears in the multifunction
display.
If your speed exceeds 
40 mph (60 km/h)
and lane markings are detected,
symbol  : is highlighted. Active Lane
Keeping Assist is ready for use.
If Standard is selected, no warning
vibration occurs if:
R you have switched on the turn signals. In
this event, the warnings are suppressed
for a certain period of time.
R a driving safety system intervenes, such
as ABS, BAS or ESP ®
.
If Adaptive is selected, no warning
vibration occurs if: Driving systems
223
Driving and parking Z