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
For vehicles with steering wheel buttons you
can have the current ATTENTION ASSIST
(Attention Level) assessment displayed.
X Select Status Overview in the Assist.
menu and display the attention level
(Y page
189).
The following information is displayed: R the length of the journey since the last
break.
R the attention level determined by ATTEN-
TION ASSIST, displayed in a bar display in
five levels from low to high.
R if ATTENTION ASSIST is unable to calculate
the attention level and cannot output a
warning, the System Passive message
appears in the display. The bar display is
then dimmed. This is the case, for example,
if you are predominantly driving at a speed
below
40 mph (60 km/h) or above 125 mph
(200 km/h).
Activating ATTENTION ASSIST X
Activating ATTENTION ASSIST with the on-
board computer:
R on vehicles without steering wheel but-
tons
(Y page 180)
R on vehicles with steering wheel buttons
(Y page 190)
For vehicles with steering wheel buttons,
the system determines the attention level of
the driver depending on the setting selec-
ted:
Standard: the sensitivity with which the
system determines the attention level is set
to normal.
Sensitive: the sensitivity is set higher. The
driver is warned earlier.
When ATTENTION ASSIST is switched on and
the vehicle engine is running: R on vehicles without steering wheel buttons,
the À indicator lamp in the instrument
cluster lights up
R on vehicles with steering-wheel buttons, the
display shows the À symbol:
- in the status area
- in the Status Overview of the Assist.
menu (Y page
189)
For vehicles with steering wheel buttons, if you
deactivate ATTENTION ASSIST, the system is
automatically re-activated when you start the engine. The system sensitivity then corre-
sponds to the last selection activated – stand-
ard or sensitive.
If you switch off ATTENTION ASSIST in a vehi-
cle without steering wheel buttons, the system
remains switched off even after you start the
engine. The status of the system after switch-
ing on the engine always corresponds to the
status last selected.
Warning in the display If the system detects tiredness or increasing
lapses in concentration, the warning
Atten‐
tion Assist: Take a Break! or Attent.
Asst: Take Break!is shown in the display.
An additional warning tone sounds.
X If necessary, take a break.
X Confirm the message by pressing the a
button on the steering wheel.
On long journeys, take regular breaks in good
time to allow yourself to rest. If you do not
take a break and ATTENTION ASSIST contin-
ues to detect increasing lapses in concentra-
tion, you will be warned again after
15 minutes
at the earliest. This will only happen if ATTEN-
TION ASSIST still detects typical indicators of
fatigue or increasing lapses in concentration. PARKTRONIC
General notes PARKTRONIC is an electronic parking aid. The
system is equipped with ultrasonic sensors in
the front and rear bumpers to monitor the area
around your vehicle. PARKTRONIC indicates
visually and audibly the distance between your
vehicle and an object.
Your vehicle features two separate sound
emitters with different frequencies for the
warning tones. The warning ranges in front of
and behind the vehicle are indicated by differ-
ent warning tones.
PARKTRONIC is activated automatically when
you:
R turn the key to position 2 in the ignition lock
R release the parking brake and
R move the selector lever to position D, N or R156
Driving systems
Driving and parking
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h
). PARKTRONIC is reactiva-
ted at speeds below 10 mph (16 km/h).
Important safety notes PARKTRONIC is only an aid. It cannot replace
your own awareness of the immediate sur-
roundings. You are responsible for safe
maneuvering, parking and pulling away. Make
sure that there are no persons, animals or
objects in the maneuvering area while maneu-
vering and parking in/leaving parking spaces.
! Pay particular attention to obstacles above
or below the sensors when parking, such as
flower pots or trailer towbars. PARKTRONIC
does not recognize such objects when they
are in the immediate vicinity of the vehicle.
You could damage the vehicle or objects.
PARKTRONIC can suffer interference from:
R ultrasonic sources such as a truck's
compressed-air brakes, an automatic car
wash or a pneumatic drill
R attachments to the vehicle, e.g. rear
mounted racks
R number plates (vehicle license plates)
that are not affixed flat against the
bumper
R dirty or icy sensors
Remove a detachable trailer coupling if it is no
longer required. PARKTRONIC measures the
minimum detection range to an obstacle from
the bumper, not the ball coupling.
Range of the sensors PARKTRONIC does not account for obstacles
that are:
R beneath its detection range, e.g. persons,
animals or objects
R above its detection range, e.g. overhanging
loads, overhangs or loading ramps of trucks The sensors must be free of dirt, ice or slush.
Otherwise, they cannot function correctly.
Clean the sensors regularly, taking care not to
scratch or damage them (Y page
267).
Front sensors Center Approx. 39 in
(100 cm
) Corners Approx. 24 in
(60 cm
) Rear sensors
Center Approx. 47 in
(120 cm
) Corners Approx. 31 in
(80 cm
) Minimum distance
Center Approx. 8 in (20 cm)
Corners Approx. 8 in (20 cm)
If an obstacle is within this range, the corre-
sponding segments of the warning displays
light up and you hear a warning tone. If the
distance falls below the minimum, the dis- Driving systems
157
Driving and parking Z
Towing a trailer
PARKTRONIC detects a coupled trailer if your
vehicle is equipped with the corresponding
electrical installations for trailer towing.
PARKTRONIC is deactivated for the rear area
when you establish an electrical connection
between your vehicle and a trailer. If you use
an adapter for the socket, remove it from the
socket after detaching the trailer. Otherwise,
PARKTRONIC remains deactivated for the rear
area.
Problems with PARKTRONIC Problem
Possible causes/consequences and
M SolutionsOnly the red segments
in the PARKTRONIC
warning displays are lit.
In addition, a warning
tone sounds for approx.
two seconds
PARKTRONIC is then
deactivated.
The indicator lamp of
the f button lights
up and the red seg-
ments in the
PARKTRONIC warning
display go out. PARKTRONIC has malfunctioned and has switched itself off.
X
If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. The PARKTRONIC warn-
ing displays implausible
distances.
For example, all the
segments may be lit
even though there is no
obstacle present. The PARKTRONIC sensors are dirty or iced up.
X Clean the PARKTRONIC sensors ( Y page 267).
X Turn the key to position 2 in the ignition lock. The license plate or other parts attached near the sensors may not
be secured correctly.
X Check the license plate and attachment parts near the sensors
for correct seating. An external radio or ultrasonic source may be causing interference.
X Check PARKTRONIC functions in a different location. Active Parking Assist
General notes Active Parking Assist is an electronic parking
aid. The system uses ultrasound sensors to
measure the road on both sides of the vehicle
and indicates suitable parking spaces. It can
then actively steer and brake the vehicle to
help you to park and exit the parking space.
Active Parking Assist includes the
PARKTRONIC parking aid which indicates visu-
ally and audibly the distance between your vehicle and an obstruction. To do this,
PARKTRONIC uses the ultrasonic sensors of
the Active Parking Assist
(Y page 156).
Important safety notes Active Parking Assist is only an aid. It is not a
substitute for your attention to the immediate
surroundings. You are responsible for safe
maneuvering, parking and pulling away. Make
sure that no persons, animals or objects are in
the maneuvering range. Driving systems
159
Driving and parking Z
Active Parking Assist does not assist you park-
ing in spaces at right angles to the direction of
travel if:
R two parking spaces are located directly next
to one another
R the parking space is directly next to a low
obstacle such as a low curb
R you forward park
Active Parking Assist does not assist you park-
ing in spaces that are parallel or at right angles
to the direction of travel if:
R the parking space is on a curb
R the system reads the parking space as being
blocked, for example by foliage or grass
paving blocks
R the area is too small for the vehicle to
maneuver into
R the parking space is bordered by an obsta-
cle, e.g. a tree, a post or a trailer :
Detected parking space on the left
; Parking symbol
= Detected parking space on the right
If the driver's seat belt is fastened and all
doors are closed, Active Parking Assist is acti-
vated automatically when driving forwards.
The system is operational at speeds of up to
approximately
22 mph (35 km/h). While in
operation, the system independently locates
and measures parking spaces on both sides of
the vehicle.
Active Parking Assist will only detect parking
spaces:
R parallel or at right angles to the direction of
travel
R that are parallel to the direction of travel
and are at least 59 in (1.5 m) wide
R that are parallel to the direction of travel
and at least 40 in (1.0 m) longer than your
vehicle
R that are at right angles to the direction of
travel and at least 40 in (1.0 m) wider than
your vehicle i
Note that Active Parking Assist cannot
measure the length of a parking space if it is
at right angles to the direction of travel. You
will need to judge whether your vehicle will
fit in the parking space.
When the vehicle is driving at speeds of up to
approximately
20 mph (30 km/h), parking
symbol ; is shown as a status display in the
header.
The system detects and differentiates between
parking spaces which are parallel or at right
angles to the direction of travel. When a park-
ing space is detected, an arrow appears next
to parking symbol ; to indicate which side
the parking space is on. The parking space is
displayed while you are driving past it and until
you are approximately 50 ft (15 m) away from
it.
Active Parking Assist displays parking spaces
on the passenger side as standard. The park-
ing spaces on the driver's side are only dis-
played if you operate the turn signal on the
driver's side. When parking on the driver's
side, you must operate the turn signal until
you have started active parking assistance by
pressing the a button on the steering
wheel.
Parking G
WARNING
If you leave the driver's seat when the vehi-
cle is only being braked by Active Parking
Assist, the vehicle could roll away if:
R there is a malfunction in the system or in
the voltage supply.
R the electrical system in the engine com-
partment, the battery or the fuses are
tampered with.
R the battery is disconnected.
R the vehicle is accelerated, e.g. by a vehi-
cle occupant.
There is a risk of an accident.
Before leaving the driver's seat, always
secure the vehicle against rolling away.
If PARKTRONIC detects obstacles, Active Park-
ing Assist brakes automatically during the
parking process. You are responsible for brak-
ing in good time. Driving systems
161
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
X
Start the engine.
X Switch on the turn signal in the direction in
which you are pulling away.
X Shift the transmission to position h or k.
The display shows the message Start
Park Assist? Yes: OK No: %.
X To cancel the process: press the % but-
ton on the steering wheel or drive off.
or
X To exit the parking space using active
parking assistance: press the a button
on the steering wheel.
The display shows the message Park
Assist Active: Accelerate and Brake
Obs. Surroundings.
X Let go of the steering wheel.
X Pull away, being ready to brake at all times.
Exit the parking space slowly and do not
drive faster than
6 mph (10 km/h). Other-
wise parking assistance is canceled and
Active Parking Assist is stopped.
Active Parking Assist brakes the vehicle to a
standstill when the vehicle approaches a
border of the parking space.
X While the vehicle is stationary, shift the
transmission to position h or k as
required or according to the message.
Active Parking Assist immediately steers in
the other direction. The display shows the
message Park Assist Active: Acceler‐
ate and Brake Obs. Surroundings.
i You will achieve the best results by waiting
for the steering procedure to complete
before pulling away.
If you back up after activation, the steering
wheel is moved to the straight-ahead posi-
tion.
X Drive forwards and reverse as prompted by
the PARKTRONIC warning displays, several
times if necessary.
Once you have exited the parking space com-
pletely:
R The display shows the Park Assist Fin‐
ished message.
R A tone sounds.
R The steering wheel is moved to the straight-
ahead position
The parking assistance function of Active Park-
ing Assist is stopped. You will then have to
steer and merge into traffic on your own.
PARKTRONIC is still available. You can take over the steering before the vehi-
cle has exited the parking space completely.
This is useful, for example when you recognize
that it is already possible to pull out of the
parking space.
Canceling active parking assistance X
Stop the movement of the steering wheel or
steer yourself.
or X Press the f button and deactivate
PARKTRONIC
(Y page 158).
Parking assistance is canceled immediately
and Active Parking Assist is stopped. The
display shows the Park Assist Canceled
message.
Active parking assistance is canceled automat-
ically in the following cases:
R you apply the parking brake.
R parking using Active Parking Assist is no
longer possible.
R you are driving faster than
6 mph
(10 km/h).
R a wheel spins and ESP ®
intervenes or fails.
The ÷ warning lamp in the instrument
cluster then lights up.
R you unfasten your seat belt.
R you open a door or the tailgate/rear-end
door.
R you shift the transmission to position j.
A warning tone sounds, the parking symbol in
the display goes out and the Park Assist
Canceled message appears.
Once active Parking Assist has been canceled,
you must steer and brake again yourself.
If a system malfunction occurs, vehicles are
automatically braked down to a standstill. To
continue driving, you must depress the accel-
erator pedal again. Rear view camera
General notes On vehicles with a tailgate, the rear view cam-
era is next to the tailgate handle
(
Y page
267).
On vehicles with rear-end doors, the rear view
camera is in the top of the license plate mold-
ing ( Y page 267). Driving systems
163
Driving and parking Z