Use cruise control if road and traffic condi-
tions make it appropriate to maintain a steady
speed for a prolonged period. You can set any
speed from 30 km/h
upwards in increments of
1 km/h and 10 km/h.
If you have set Miles as the unit for the digital
speedometer , you can set any speed above
20 mph in increments of 1 mph and 5 mph.
Changing the display unit for the digital speed-
ometer and the distance:
R on vehicles without steering wheel buttons
(Y page 180)
R on vehicles with steering wheel buttons
(Y page 192)
Cruise control should not be activated when
driving off-road or on construction sites.
Cruise control may be unable to maintain the
stored speed on uphill gradients. The stored
speed is resumed if the uphill gradient evens
out and the vehicle's speed does not fall below
20 mph (30 km/h). Cruise control maintains
the stored speed on downhill gradients by
automatically applying the brakes. Observe the
additional driving tips (Y page 142).
Important safety notes Observe the notes on braking (Y page
142).
If you fail to adapt your driving style or if you
are inattentive, cruise control can neither
reduce the risk of an accident nor override the
laws of physics. Cruise control cannot take
road, weather and traffic conditions into
account. Cruise control is only an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in lane.
If you change wheel size, make sure they cor-
respond to the correct wheel size category
(Y page 278). If the category is changed with- out recoding the control units in the vehicle,
the functioning of cruise control may be
impaired.
Do not use cruise control:
R in traffic conditions that are unsuitable for
driving at a constant speed, e.g. in heavy
traffic, on winding roads or off-road.
R on slippery roads. Braking or accelerating
may cause the drive wheels to lose traction
and the vehicle could then skid.
R when there is poor visibility, e.g. due to fog,
heavy rain or snow. If there is a change of drivers, make sure that
you inform the new driver about the set cruise
speed.
Cruise control lever and display :
To activate and store the current speed or
a higher speed
; To activate at the last stored speed
= To activate and store the current speed or
a lower speed
? To deactivate cruise control
The cruise control lever is the lower lever on
the left of the steering column.
When you activate cruise control, the display
briefly shows the Cruise Control message
and the stored speed.
The display also shows the V symbol and
the stored speed:
R in the header on vehicles without steering
wheel buttons (Y page
176)
R in the status area on vehicles with steering
wheel buttons (Y page 183)
Activation conditions To activate cruise control, all of the following
activation conditions must be fulfilled:
R the parking brake must be released. The
F (only USA) or J (only Canada) indi-
cator lamp in the instrument cluster goes
out
R ESP ®
must be switched on, but not currently
intervening or performing a control action
R you are driving faster than
20 mph
(30 km/h)
R the brake pedal is not depressed Driving systems
147
Driving and parking Z
may also cause the system to display a warn-
ing.
If you fail to adapt your driving style, the dis-
tance warning function can neither reduce the
risk of an accident nor override the laws of
physics. The distance warning function cannot
take into account road, weather or traffic con-
ditions. The distance warning function is only
an aid. You are responsible for the distance to
the vehicle in front, for vehicle speed, braking
in good time and for staying in your lane.
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to collisions
at slow speeds where there is no visible dam-
age to the front of the vehicle.
If you change wheel size, make sure they cor-
respond to the correct wheel size category
(Y page
278). If the category is changed with-
out recoding the control units in the vehicle,
the functioning of the distance warning feature
may be impaired. COLLISION PREVENTION
ASSIST may then detect a malfunction and
switch itself off.
Operation
X To activate/deactivate: activate or deacti-
vate the distance warning function in the on-
board computer
(Y page 190).
If the distance warning function of COLLI-
SION PREVENTION ASSIST is activated, the
display shows the Ä symbol:
R in the header
R in the Status Overview of the Assist.
menu (Y page 189)
At speeds up to approx 20 mph (30 km/h)
the display in vehicles with Active Parking
Assist first shows the í status indicator.
Only from a speed of about 20 mph
(30 km/h) does the display show the
Äsymbol instead of the í status indica-
tor.
The distance warning function can help you to
minimize the risk of a front-end collision with a
vehicle ahead or reduce the effects of such a
collision. With the help of the radar sensor sys-
tem, the distance warning function can detect
obstacles that are in the path of your vehicle
for an extended period of time. If the distance
warning function detects that there is a risk of
a collision, you will be warned visually and,
where necessary, acoustically. Without your intervention, the distance warning function
cannot prevent a collision.
The distance warning function issues a warn-
ing at speeds:
R from about
4 mph (7 km/h) if you approach
a vehicle traveling in front or a stationary
vehicle too quickly. The · warning lamp
in the instrument cluster then lights up and
an intermittent warning tone also sounds.
At speeds up to about 45 mph (70 km/h),
the system also detects stationary obsta-
cles, for example stopped or parked vehi-
cles.
X Brake immediately until the distance from
the obstacle increases and the risk of a
front-end collision passes.
or X Take evasive action, provided it is safe to do
so.
Adaptive Brake Assist General notes
Adaptive Brake Assist evaluates the traffic sit-
uation with the help of the radar sensor sys-
tem and can detect obstacles which have been
in your vehicle's path for an extended period
of time. From speeds above 4 mph (7 km/h
),
Adaptive Brake Assist aids you in braking dur-
ing hazardous situations.
Up to a speed of approximately 125 mph
(200 km/h), Adaptive Brake Assist is capable
of reacting to moving obstacles that have
already been detected as such at least once
over the period of observation.
Important safety notes G
WARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R to stationary obstacles
R when cornering
As a result, the Adaptive Brake Assist may
not intervene in all critical conditions. There
is a risk of an accident. 150
Driving systems
Driving and parking
Always pay careful attention to the traffic
situation and be ready to brake. G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. Terminate
the intervention in a non-critical driving sit-
uation.
In particular, the detection of obstacles can be
impaired in the case of:
R dirt on the sensors or anything else covering
the sensors
R snow or heavy rain
R interference from other radar sources
R strong radar reflections, for example, in
parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause Adaptive Brake Assist to inter-
vene.
If you fail to adapt your driving style, Adaptive
Brake Assist can neither reduce the risk of
accident nor override the laws of physics.
Adaptive Brake Assist cannot take into
account road, weather or traffic conditions.
Adaptive Brake Assist is only an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, braking in good time
and for staying in your lane.
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to collisions
at slow speeds where there is no visible dam-
age to the front of the vehicle.
If you change wheel size, make sure they cor-
respond to the correct wheel size category
(Y page
278). If the category is changed with- out recoding the control units in the vehicle,
the functioning of Adaptive Brake Assist may
be impaired. COLLISION PREVENTION ASSIST
may then detect a malfunction and switch
itself off.
If Adaptive Brake Assist is not available due to
a malfunction in the radar sensor system, the
brake system remains available with full brake
boosting effect and BAS.
Operation With the help of the radar sensor system,
Adaptive Brake Assist can detect obstacles
that have been in the path of your vehicle for
an extended period of time. Adaptive Brake
Assist does not react to stationary obstacles.
If Adaptive Brake Assist detects a risk of colli-
sion with a vehicle traveling in front or with a
stationary obstacle, the system calculates the
braking force necessary to avoid this collision.
If you apply the brakes forcefully, Adaptive
Brake Assist will automatically increase the
braking force to a level suitable for the traffic
conditions.
X Brake until the distance to the obstacle
increases and the risk of a collision passes.
ABS prevents the wheels from locking.
The brakes function as usual again if:
R you release the brake pedal
R there is no longer any danger of a collision
R no obstacle is detected in front of your vehi-
cle
Braking assistance is then ended. Blind Spot Assist
General notes Blind Spot Assist monitors the areas on either
side of the vehicle that are not visible to the
driver with two lateral, rear-facing radar sen-
sors in the bumper. It supports you from
speeds of approximately
20 mph (30 km/h). A
warning display in the exterior mirrors draws
your attention to vehicles detected in the
monitored area. If you then switch on the cor-
responding turn signal to change lane, you will
also receive an optical and audible collision
warning. Driving systems
151
Driving and parking Z
means of intermittent vibration through the
steering wheel for up to
1.5 seconds.
Important safety notes G
WARNING
Lane Keeping Assist cannot always clearly
detect lane markings.
In such cases, Lane Keeping Assist can:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, espe-
cially if Lane Keeping Assist alerts you. G
WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There
is a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane
Keeping Assist.
If you fail to adapt your driving style, Lane
Keeping Assist can neither reduce the risk of
accident nor override the laws of physics.
Lane Keeping Assist cannot take into account
road, weather or traffic conditions. Lane Keep-
ing Assist is only an aid. You are responsible
for the distance to the vehicle in front, for
vehicle speed, braking in good time and for
staying in your lane.
Lane Keeping Assist does not keep your vehi-
cle in its lane.
The system may be impaired or may not func-
tion if:
R there is poor visibility, e.g. due to insuffi-
cient 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
(e.g. if the road surface is wet)
R the windshield is dirty, fogged up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R there are no lane markings, or several
unclear lane markings for one lane, e.g.
around construction sites 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
short and thus the lane markings cannot be
detected
R the lane markings change quickly, e.g. lanes
branch off, cross one another or merge
R the road is narrow and winding
R there are highly variable shade conditions
on the road
Deactivating and activating Lane Keep-
ing Assist X
Press the Ç button.
If the indicator lamp in the button lights up
and the display shows the Ç symbol in
the status area, Lane Keeping Assist is
switched on but not ready for use.
If you are driving with Lane Keeping Assist
activated at speeds above
40 mph
(60 km/h) and lane markings are detected,
the display shows the Ç symbol highligh-
ted in the status area. Lane Keeping Assist
is then ready for use. Status indicators in the status overview submenu
The display in the Status Overview submenu
of the on-board computer also shows the sta-
tus of Lane Keeping Assist
(Y page 189). If
Lane Keeping Assist is activated but not ready
for use, the display shows the lane markings in
the symbol as broken lines :. If Lane Keeping154
Driving systems
Driving and parking
Assist is ready for use, the lane markings in
the symbol are shown as solid lines
;.
Setting the sensitivity of Lane Keeping
Assist X
In the Assist. menu on the on-board com-
puter, select the Lane Keeping Assist:
function
(Y page 191).
X Select Standard or Adaptive.
In the Standard setting, no warning vibration
occurs if:
R you operate the turn signal in the corre-
sponding direction. In this event, the warn-
ings are suppressed for a certain period of
time.
R a driving safety system, such as ABS, BAS or
ESP ®
, intervenes or performs a control
action.
When Adaptive is selected, there is also no
warning vibration when: R you accelerate hard, e.g. kickdown.
R brake sharply.
R you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when neces-
sary and in good time if you cross the lane
marking, the system differentiates between
various 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, such as a
highway.
R the system detects solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend. Alertness Assistant ATTENTION
ASSIST
General notes ATTENTION ASSIST helps you during long,
monotonous journeys such as on freeways and
interstate highways. It is active in the 40 mph
(
60 km/h) to 125 mph (200 km/h) range. If
ATTENTION ASSIST detects typical indicators of fatigue or increasing lapses in concentration
on the part of the driver, it suggests taking a
break.
Important safety notes ATTENTION ASSIST is only an aid. The system
may not always detect fatigue or lapses in
concentration until too late, or may not detect
them at all. ATTENTION ASSIST is not a substi-
tute for a well-rested and attentive driver.
The functionality of ATTENTION ASSIST is
restricted, and warnings may be delayed or
not occur at all:
R if the length of the journey is less than
approximately
30 minutes
R if the road condition is poor, e.g. if the sur-
face is uneven or if there are potholes
R if there is a strong side wind
R if you have adopted a sporty driving style
with high cornering speeds or high rates of
acceleration
R if you are predominantly driving at a speed
below 40 mph (60 km/h) or above 125 mph
(200 km/h)
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
ATTENTION ASSIST is reset and starts assess-
ing your attention again when you continue
your journey if:
R you switch off the engine
R you take off your seat belt and open the
driver's door, e.g. for a change of drivers or
to take a break
Displaying the attention level Driving systems
155
Driving and parking Z
X
Bring the vehicle safely to a stop when the
parking symbol shows the desired parking
space in the instrument cluster.
X Shift the transmission to position k.
The display shows the Start Park
Assist? Yes: OK No: % message and
the location of the parking space.
X To cancel the process: press the % but-
ton on the steering wheel or drive off.
or X To park using active parking assistance:
press the a button on the steering
wheel.
The display shows the
Park Assist
Active: Accelerate and Brake Obs.
Surroundings message.
X Let go of the steering wheel.
X Reverse the vehicle, being ready to brake at
all times. Exit the parking space slowly and
do not drive faster than
6 mph (10 km/h).
Otherwise parking assistance is canceled
and Active Parking Assist is stopped.
Active Parking Assist brakes the vehicle to a
standstill when the vehicle approaches the
rear border of the parking space.
Maneuvering may be required in tight parking
spaces. The display shows the Park Assist
Active: Select D Obs. Surroundings
message.
X While the vehicle is stationary, shift the
transmission to position h.
Active Parking Assist immediately steers in
the other direction. The display shows the
Park Assist Active: Accelerate and
Brake Obs. Surroundings message.
i You will achieve the best results by waiting
for the steering procedure to complete
before pulling away.
X Drive forwards and be ready to brake at all
times.
Active Parking Assist brakes the vehicle to a
standstill.
The display shows the Park Assist
Active: Select R Obs. Surroundings
message.
As soon as the parking procedure is complete,
the Park Assist Finished message appears
in the display and a tone sounds. The parking
assistance function of Active Parking Assist is
stopped. The vehicle is parked and kept sta-
tionary without the driver having to depress the brake pedal. The braking effect is canceled
when you depress the accelerator pedal.
Active Parking Assist no longer supports you
with steering interventions and brake applica-
tions. Once active parking assistance has been
stopped, you must steer and brake again your-
self. PARKTRONIC is still available.
Parking tips:
R The way your vehicle is positioned in the
parking space after parking is dependent on
various factors. These include the position
and shape of the vehicles parked in front
and behind it and the conditions of the loca-
tion. It may be the case that Active Parking
Assist guides you too far into a parking
space, or not far enough into it. In some
cases, it may also lead you across or onto
the curb. In this case, cancel the active
parking assistance.
R You can also engage transmission position
h prematurely. The vehicle redirects and
does not drive as far into the parking space.
If you change direction too early, parking
assistance is canceled and Active Parking
Assist is stopped. It is then not possible to
achieve a sensible parking position from the
current position.
Exiting a parking space In order that Active Parking Assist can assist
you when exiting the parking space, the follow-
ing conditions must be fulfilled:
R the border of the parking space must be
high enough at the front and the rear, a
curb, for instance, is not sufficient.
R the border of the parking space must not be
too wide. Your vehicle can be maneuvered
into a position at a maximum of 45° to the
starting position in the parking space.
R a maneuvering distance of at least
3.3 ft
(1.0 m) must be available.
Active Parking Assist can only assist you with
exiting a parking space if you have parked the
vehicle parallel to the direction of travel using
Active Parking Assist.
If PARKTRONIC detects obstacles, Active Park-
ing Assist brakes automatically when exiting
from the parking space. You are responsible
for braking in good time. 162
Driving systems
Driving and parking
Switching the rear view camera on or
off
X
To activate: make sure that the key is in
position 2 in the ignition lock.
X Shift the transmission to position k.
On vehicles with a tailgate, the rear view
camera flap opens. The audio display shows
the area behind the vehicle. The rear area
shown is divided by guide lines.
In vehicles with a trailer coupling installed, the
function mode of the rear view camera can be
switched over when the trailer is reached. The
rear view camera then changes the viewing
angle and shows a locating aid for the ball cou-
pling of the trailer tow hitch to help reach the
drawbar.
X To switch function mode: select and con-
firm "Reverse parking" function : or "Cou-
pling up a trailer“ function ; using the
audio system control knob.
Information on the audio system control
knob can be found in the separate operating
instructions.
The symbol of the selected function is high-
lighted.
X To switch off: shift the transmission to
position i or h.
The dynamic guide lines are hidden and
after about 15 seconds the rear view cam-
era switches itself off.
or X Drive forwards more than about 30 ft
(10 m).
or X Drive forwards faster than 6 mph
(10 km/h
).
or X Shift the automatic transmission to position
j. In vehicles with Active Parking Assist, the rear
view camera remains switched on after the ini-
tial shift to reverse gear for the whole duration
of active parking assistance. You can find
information on active parking assistance under
"Active Parking Assist“
(Y page 159).
Messages in the multimedia system
display :
Yellow guide line at a distance of approx-
imately
13 ft (4.0 m) from the rear of the
vehicle
; White guide line without turning the steer-
ing wheel, vehicle width including the exte-
rior mirrors (static)
= Yellow guide line for the vehicle width
including the exterior mirrors, at the cur-
rent steering angle (dynamic)
? Yellow lane marking the course the tires
will take at the current steering angle
(dynamic) A
Yellow guide line at a distance of approx-
imately
3 ft (1.0 m) from the rear of the
vehicle
B Red guide line at a distance of approx-
imately
12 in (0.30 m) from the rear of the
vehicle
C Bumper
D Vehicle center axis (locating aid) Driving systems
165
Driving and parking Z
Useful information
This Operator's Manual describes all models
as well as standard and optional equipment of
your vehicle that were available at the time of
going to print. Country-specific variations are
possible. Note that your vehicle may not be
equipped with all of the described functions.
This also applies to systems and functions rel-
evant to safety.
Read the information on qualified specialist
workshops (Y page
32).Important safety notes
G
WARNING
If you operate information systems and com-
munication equipment integrated in the
vehicle when driving, you may be distracted
from the traffic situation. You could also
lose control of the vehicle. There is a risk of
an accident.
Only operate this equipment when the traffic
situation permits. If you are not sure that
this is possible, park the vehicle paying
attention to traffic conditions and operate
the equipment when the vehicle is station-
ary. G
WARNING
If you are driving and reach through the
steering wheel to operate the adjustment
knob, you could lose control of the vehicle.
There is a risk of an accident and injury.
Only operate the adjustment knobs when
the vehicle is stationary. Do not reach
through the steering wheel when driving.
You must observe the legal requirements for
the country in which you are currently driving
when operating the on-board computer. G
WARNING
If the instrument cluster has failed or mal-
functioned, you may not recognize function
restrictions in systems relevant to safety. The operating safety of your vehicle may be
impaired. There is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
The on-board computer display only shows
messages and warnings from certain systems.
You should therefore make sure your vehicle is
operating safely at all times. If the operating
safety of your vehicle is impaired, stop the
vehicle as soon as possible, paying attention
to road and traffic conditions. Then consult a
qualified specialist workshop.
The accuracy of the speedometer and odome-
ter displays is legally prescribed. Determining
the speed is dependent on the wheel size or
the rolling circumference of the wheels. If you
change the wheel size on your vehicle, make
sure it is assigned to the correct wheel size
category ( Y page
278). If you change wheel
size category without recoding the control
unit, the speedometer indication will be inac-
curate. Driving safety and driving systems may
be impaired or detect a malfunction and shut
down.
An overview of the instrument cluster can be
found under "Instrument cluster":
R for vehicles without steering wheel buttons
(Y page 38)
R for vehicles with steering wheel buttons
(Y page 40) Display and operation
Instrument lighting
Brightness control knob (example: vehicle with
steering wheel buttons)174
Display and operation
On-board computer and displays