
Always pay careful attention to the traffic
situationand be ready to brake.
The distance warning functioncannot always
clearly identify objects and complextraffic
situations.
In such cases, the distance warning function
may:
Rgive an unnecessary warning
Rnot give a warning
Always pay careful attention to the traffic
situation and do not rely solely on the
distance warning function.
Function
XTo activate/deactivate:activate or
deactivate the distance warning function in
the on-board computer (Ypage 204).
If the distance warning function is not
activated, the symbol appears in the
assistance graphics display.
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. If the distance warning
function detects that there is a risk of a
collision, you will be warned visually and
acoustically.Without your intervention, the
distance warning function cannot prevent a
collision.
Starting at a speed of around 4 mph
(7 km/h) the distancewarning function warns
you if you rapidly approach a vehicle in front.
An intermittentwarning tone will then sound,
and the distance warning lamp will light
up in the instrument cluster.
XBrake immediately in order to increase the
distance from the vehicle in front.
or
XTake evasive action provideditis safe to do
so.
For the distance warning function to assist
you when driving, the function must be
activated in the on-board computer and be
operational (Ypage 204).
Due to the nature of the system, particularly
complicated but non-critical driving
conditions may also cause the system to
display a warning.
With the help of the radar sensor system, the
distance warning function can detect
obstacles that are in the path of your vehicle
for an extended period of time.
From a speed of around 40 mph (70 km/h),
the distance warning function can also react
to stationary obstacles, such as stopped or
parked vehicles.
If you approach an obstacle and the distance
warning function detects a risk of a collision,
the system will initially alert you both visually
and acoustically.
In particular, the detection of obstacles can
be impaired if:
Rdirt on the sensors or anything else
covering the sensors
Rsnow or heavy rain
Rinterference by other radar sources
Rthere are strong radar reflections, for
example in parking garages
Ra narrow vehicle traveling in front, e.g. a
motorbike
Ra vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensor checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
Adaptive Brake Assist
iObserve the "Important safety notes"
section for driving safety systems
(Ypage 61).
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic
situations. In these cases, Adaptive Brake
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Assist may not intervene. There is a riskofan
accident.
Always pay careful attention to the traffic
situationand be ready to brake.
GWARNING
Adaptive Brake Assist does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rto stationary obstacles
Rwhen cornering
As a result, Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic
situationand be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving
conditions may also cause Brake Assist to
intervene.
Adaptive Brake Assist aids you in braking
during hazardous situations at speeds above
4mph (7 km/h) and uses the radar sensor
system to evaluate the traffic situation.
With the help of a sensorsystem, adaptive
Brake Assistcan detect obstacles that are in
the path of your vehicle for an extended
period of time.
Should you approach an obstacle and
Adaptive Brake Assist has detected a riskof
collision, Adaptive Brake Assist calculates the
braking force necessary to avoid a rear-end
collision. Should you apply the brakes
vigorously, Adaptive Brake Assist will
automatically increase the braking force to a
level suitable for the traffic conditions.
XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally againif:
Ryou release the brake pedal
Rthere is no longerany dangerofarear-end
collision.
Rno obstacle is detected in front of your
vehicle
Adaptive Brake Assist is then deactivated.
Up to vehicle speeds of around 155 mph
(250 km/h), adaptive Brake Assist is capable
of reacting to moving objects that have
already been recognized as such at least once
over the period of observation. Adaptive
Brake Assist does not react to stationary
obstacles.
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.
In particular, the detection of obstacles can
be impaired if there is:
Rdirt on the sensors or anything else
covering the sensors
Rsnow or heavy rain
Rinterference by other radarsources
Rthere are strong radar reflections, for
example in parking garages
Ra narrow vehicle traveling in front, e.g. a
motorbike
Ra vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensor checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
COLLISION PREVENTION ASSIST PLUS
General information
COLLISION PREVENTION ASSIST PLUS is
only available on vehicles with DISTRONIC.
COLLISION PREVENTION ASSIST PLUS
extends the functionality of COLLISION
PREVENTION ASSIST with an automatic
64Driving safety systems
Safety

braking function. COLLISION PREVENTION
ASSIST PLUS can help you to minimize the
risk of a front-end collision with a vehicle
ahead or reduce the effects of such a
collision. If COLLISION PREVENTION ASSIST
PLUS detects that thereis a risk of a collision,
you will be warned visually and acoustically.
In critical situations COLLISION PREVENTION
ASSIST PLUS also initiates automatic
braking.
Function
XTo activate/deactivate:activate or
deactivate COLLISION PREVENTION
ASSIST PLUS in the on-board computer
(Ypage 204).
If COLLISION PREVENTION ASSIST PLUS is
deactivated, the symbol appears in the
assistance graphics display.
If the driver's seat belt is fastened,
COLLISION PREVENTION ASSIST PLUS can
brake automatically withinaspeed range of
between 4 mph (7 km/h) and 124 mph
(200 km/h).
COLLISION PREVENTION ASSISTPLUS can
also react to stationary obstacles with
automatic braking within a speed range of
between 4 mph (7 km/h) and 19 mph
(30 km/h).
In particular, the detection of obstacles can
be impaired if:
Rdirt on the sensors or anything else
covering the sensors
Rsnow or heavy rain
Rinterference by other radarsources
Rthere are strong radar reflections, for
example in parking garages
Ra narrow vehicle traveling in front, e.g. a
motorbike
Ra vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensor checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
ESP®(Electronic Stability Program)
General notes
iObserve the "Important safety notes"
section (Ypage 61).
ESP®monitors driving stability and traction,
i.e. power transmission between the tires and
the road surface.
If ESP®detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. The engine output is also modified to
keep the vehicle on the desired course within
physical limits. ESP®assists the driver when
pulling away on wet or slippery roads. ESP®
can also stabilize the vehicle during braking.
ETS/4ETS (Electronic Traction System)
iObserve the "Important safety notes"
section (Ypage 61).
ETS/4ETS traction control is part of ESP®.
ETS brakes the drive wheels individually if
they spin. This enables you to pull away and
accelerate on slippery surfaces, for example
if the road surface is slippery on one side. In
addition, more drive torque is transferred to
the wheel or wheels with traction.
ETS remains active when you deactivate
ESP®.
Important safety notes
GWARNING
If ESP®is malfunctioning, ESP®is unable to
stabilize the vehicle. Additionally, further
driving safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP®checked at a
qualified specialist workshop.
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GWARNING
DISTRONIC PLUS cannot always clearly
identify other road users and complextraffic
situations.
In such cases, DISTRONIC PLUS may:
Rgive an unnecessary warning and then
brake the vehicle
Rneither give a warning nor intervene
Raccelerate unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, in particular when warned to do so by
DISTRONIC PLUS.
GWARNING
DISTRONIC PLUS brakes yourvehicle with up
to 50% of the maximum possible deceleration.
If this braking force is insufficient, DISTRONIC
PLUS warns you visually and audibly.There is
a risk of an accident.
In such cases, apply the brakes yourself and
try to take evasive action.
!If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes
automatically in certain situations. To
prevent damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or other similar situations:
Rwhen towing the vehicle
Rin the car wash
If you fail to adapt your driving style,
DISTRONIC PLUS can neither reduce the risk
of accident nor override the laws of physics.
DISTRONIC PLUS cannot take into account
the road, traffic and weather conditions.
DISTRONIC PLUS 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 your lane.
Do not use DISTRONIC PLUS:
Rin road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
Ron slippery road surfaces. Braking or
accelerating could cause the drive wheels
to lose traction and the vehicle could then
skid
Rwhen there is poor visibility, e.g. due to fog,
heavy rain or snow
DISTRONIC PLUS may not detect narrow
vehicles driving in front, e.g. motorcycles, or
vehicles driving on a different line.
In particular, the detection of obstacles can
be impaired if:
Rdirt on the sensors or anything else
covering the sensors
Rsnow or heavy rain
Rinterference by other radar sources
Rstrong radar reflections, for example, in
parking garages
If DISTRONIC PLUS no longer detects a
vehicle in front, DISTRONIC PLUS may
unexpectedly accelerate the vehicle to the
stored speed.
This speed may:
Rbe too high if you are driving in a filter lane
or an exit lane
Rbe so high when driving in the right-hand
lane that you overtake vehicles in the left-
hand lane
Rbe so high when driving in the left-hand lane
that you overtake vehicles in the right-hand
lane
If there is a change of drivers, advise the new
driver of the speed stored.
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PARKTRONIC
Important safety notes
PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It monitors the area
around your vehicle using six sensors in the
front bumper and six sensors in the rear
bumper. PARKTRONIC indicates visually and
audibly the distance between your vehicle
and an object.
PARKTRONIC is only an aid. It is not a
replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking
and exiting a parking space. When
maneuvering, parking or pulling out of a
parking space, make sure that there are no
persons, animals or objectsinthe area in
which you are maneuvering.
!When parking, pay particular attention to
objects above or below the sensors, such
as flower pots or trailer drawbars.
PARKTRONIC does not detect such objects
when they are in the immediate vicinity of
the vehicle. You could damage the vehicle
or the objects.
The sensors may not detect snow and other
objects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic
car wash, the compressed-air brakes on a
truck or a pneumatic drill could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
PARKTRONIC is activated automatically when
you:
Rswitch on the ignition
Rshift the transmission to positionD,RorN
Rrelease the electric parking brake
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h). It is reactivated at lower
speeds.
Range of the sensors
General notes
PARKTRONIC does not take objects into
consideration that are:
Rbelow the detection range, e.g. people,
animals or objects
Rabove the detection range, e.g.
overhanging loads, truck overhangs or
loading ramps.
Sensors in the front bumper, left-hand
side (example)
Side view
Top view
The sensors must be free from dirt, ice or
slush. They can otherwise not function
correctly. Cleanthe sensors regularly, taking
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Driving and parking
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care not to scratch or damage them
(Ypage 289).
Front sensors
CenterApprox. 40in (approx.
100cm)
CornersApprox. 24in (approx.
60cm)
Rear sensors
CenterApprox. 48 in (approx.
120 cm)
CornersApprox. 32in (approx.
80cm)
Minimum distance
CenterApprox. 8in (approx. 20cm)
CornersApprox. 8in (approx. 20cm)
If there is an obstacle within this range, the
relevant warning displays light up and a
warning tone sounds. If the distance falls
below the minimum, the distance may no
longer be shown.
Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located
on the dashboard above the center airvents.
The warning display for the rear area is
located on the headliner in the rear
compartment.
Warning display for the frontarea
Segments on the left-hand side of the
vehicle
Segments on the right-hand side of the
vehicle
"Segments showing operational readiness
The warning display for each side of the
vehicle is divided into five yellow and two red
segments. PARKTRONIC is operational if
yellow segments showing operational
readiness "light up.
The selected transmission position and the
directioninwhich the vehicle is rolling
determine which warning display is active
when the engine is running.
Transmission
position
Warning display
DFront area activated
R,Nor the vehicle
is rolling
backwards
Rear and front areas
activated
PNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
From the:
Rsixth segment onwards, you will hear an
intermittent warning tone for
approximately two seconds.
Rseventh segment onwards, you will hear a
warning tone for approximately two
176Driving systems
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