Immediately brake the vehicle to increase
your distance to the preceding vehicle. The
warning sound is intended as a final caution
in which you should intercede with your own
braking inputs to avoid a potentially
dangerous situation. Do not wait for the
operation of the warning signal to intercede
with your own braking. This will result in
potentially dangerous emergency braking
which will not always result in an impact being
avoided.
Tailgating increases the risk of an accident.GWARNING
DISTRONIC PLUS brakes your vehicle with a
maximum deceleration of 13 ft/s 2
(4 m/s 2
).
This is equivalent to approximately 40 % of
your vehicle's maximum possible
deceleration.
You need to brake yourself to prevent a
collision. DISTRONIC PLUS brakes the vehicle
to restore the set distance from the vehicle
ahead or the set speed.
GWARNING
If you do not receive visual or acoustic
warning signals during a critical traffic
situation, DISTRONIC PLUS has either not
recognized the collision risk, has been
deactivated or is malfunctioning.
Remember, whether or not DISTRONIC PLUS
is operating, it is ultimately always the drivers
responsibility to apply the brakes in order to
control the vehicle and avoid a collision.
Cruise control lever:To store the current speed or a higher
speed;To store the current speed or a lower
speed=To deactivate DISTRONIC PLUS?To store the current speed or to call up
the last stored speedATo set the specified minimum distance
Switching on DISTRONIC PLUS, storing
the current speed and maintaining it
Important safety notes
GWARNING
The vehicle can be braked when DISTRONIC
PLUS is activated. For this reason, deactivate
DISTRONIC PLUS if the vehicle is to be set in
motion by other means (e.g. in a car wash or
by towing).
In order to activate DISTRONIC PLUS, the
following conditions must be fulfilled:
R the engine must be started. It may take up
to two minutes after pulling away before
DISTRONIC PLUS is operational.
R the parking brake must not be applied.
R ESP ®
must be activated but not
intervening.
R the transmission must be in position D.
R the hood must be closed.
R the driver's door must be closed when you
shift from P to D or your seat belt must be
fastened.
168Driving systemsDriving and parking
Rthe front-passenger door must be closed.
R the vehicle must not skid.
Activating while driving
When driving at speeds below 20 mph
(30 km/h) , you can only activate DISTRONIC
PLUS if the vehicle in front has been detected
and is shown in the multifunction display. If
the vehicle in front is no longer detected and
shown, DISTRONIC PLUS is deactivated and
a warning tone sounds.XBriefly pull the cruise control lever towards
you ?, or briefly press up : or down ;.
DISTRONIC PLUS is selected.XKeep the cruise control lever pressed
up : or down ; until the desired speed
is set.XRemove your foot from the accelerator
pedal.
Your vehicle adapts its speed to that of the
vehicle in front, but only up to the desired
stored speed.
i If you do not fully release the accelerator
pedal, the DISTRONIC PLUS Override
message is shown in the multifunction
display. The set distance to a slower-
moving vehicle in front will then not be
maintained. You will be driving at the speed
you determine by the position of the
accelerator pedal.
Activating when driving towards a
stationary vehicle
If the vehicle in front of you is stationary, you
can only activate DISTRONIC PLUS once your
vehicle is stationary as well.
XBriefly pull the cruise control lever towards
you ?, or briefly press up : or down ;.
DISTRONIC PLUS is selected.
i DISTRONIC PLUS can only be activated at
under 20 mph (30 km/h) if a vehicle in front
has been detected. Therefore, the
DISTRONIC PLUS distance display in the
instrument cluster should be activated
( Y page 206).
XKeep the cruise control lever pressed
up : or down ; until the desired speed
is set.
i You can use the cruise control lever to set
the stored speed and the control on the
cruise control lever to set the specified
minimum distance ( Y page 171).
Pulling away
XIf the vehicle in front pulls away: remove
your foot from the brake pedal.XBriefly pull the cruise control lever towards
you ?.
or
XAccelerate briefly.
Your vehicle pulls away and adapts its
speed to that of the vehicle in front.
Driving
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control.
If a slower-moving vehicle is detected in front,
DISTRONIC causes your vehicle to brake. This
maintains the preset distance to the vehicle
in front.
If DISTRONIC PLUS detects a faster-moving
vehicle in front, it increases the driving speed
of your vehicle, but only up to the desired
speed you have stored.
GWARNING
If you depress the brake, DISTRONIC PLUS is
deactivated unless your vehicle is stationary.
DISTRONIC PLUS then no longer brakes your
vehicle. In such cases, control the distance
from vehicles travelling in front with the brake
alone. You could otherwise cause an accident
and thereby injure yourself and others. The
driver remains fully responsible for the
vehicle's distance from other vehicles, the
speed being driven and for braking in good
time.
Driving systems169Driving and parkingZ
Changing lanes
If you wish to change to the passing lane (in
left-hand-drive vehicles, the passing lane is
the left-hand lane), DISTRONIC PLUS
supports you if:
R you are driving faster than 40 mph
(60 km/h).
R DISTRONIC PLUS is maintaining the
distance to a vehicle in front.
R you switch on the appropriate turn signals.
R DISTRONIC PLUS does not detect a danger
of collision.
If these conditions are met, your vehicle is
accelerated. Acceleration will be interrupted
if changing lanes takes too long or if the
distance between your vehicle and the
vehicle in front becomes too small.GWARNING
DISTRONIC PLUS and Active Blind Spot Assist
are only aids designed to assist driving.
They do not relieve you of the responsibility
of paying attention. The driver remains fully
responsible for the vehicle's distance from
other vehicles, the vehicle's speed and for
braking in good time. 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.
Stopping
GWARNING
Never get out of the vehicle when DISTRONIC
PLUS is activated.
DISTRONIC PLUS must also never be
operated, activated or deactivated by a
passenger or from outside the vehicle.
DISTRONIC PLUS does not replace the
parking brake and must not be used for
parking.
The DISTRONIC PLUS braking effect is
canceled and the vehicle can start moving if:
R DISTRONIC PLUS is deactivated using the
cruise control lever.
R you accelerate.
R there is a malfunction in the system or an
interruption in the power supply, e.g.
battery failure.
R the electrical system in the engine
compartment, the battery or the fuses are
tampered with.
R the battery is disconnected.
If you wish to leave the vehicle or park it,
deactivate DISTRONIC PLUS and secure the
vehicle against rolling away.
If DISTRONIC PLUS detects that the vehicle
in front is stopping, it brakes your vehicle until
it is stationary.
Once your vehicle is stationary, it remains
stationary and you do not need to depress the
brake.
i Depending on the specified minimum
distance, your vehicle will come to a
standstill at a sufficient distance behind the
vehicle in front. The specified minimum
distance is set using the control on the
cruise control lever.
You will see a warning message in the
multifunction display if DISTRONIC PLUS is
activated and:
R the driver's door is open and the driver's
seat belt is unfastened.
R the engine is switched off.
R the hood is opened.
Shift to 'P'XMove the selector lever to P to prevent the
vehicle from rolling away.
DISTRONIC PLUS is deactivated. The
warning message in the multifunction
display disappears.170Driving systemsDriving and parking
Ryou pull the cruise control lever towards
you in order to pull away and the front-
passenger door is open.
R the vehicle has skidded.
If DISTRONIC PLUS is deactivated, you will
hear a warning tone. The DISTRONIC PLUS
Off message is shown in the multifunction
display for approximately five seconds.
If the vehicle has been stopped by DISTRONIC
PLUS and a malfunction occurs in the system,
the Brake Immediately message appears in
the multifunction display. Depress the brake
pedal immediately so that the vehicle does
not roll away. DISTRONIC PLUS is then
deactivated, and the message disappears.GWARNING
The DISTRONIC PLUS switches off and
releases the brakes when the vehicle
decelerates below the minimum speed of
20 mph (30 km/h) by operation of the system
unless the DISTRONIC PLUS detects a vehicle
directly ahead of you. At that time the driver
must apply the brakes in order to reduce
vehicle speed further or bring it to a stop.
Tips for driving with DISTRONIC PLUS
Important safety notes
The following contains descriptions of certain
road and traffic conditions in which you must
be particularly attentive. In such situations,
brake if necessary. DISTRONIC PLUS is then
deactivated.
GWARNING
The DISTRONIC PLUS works to maintain the
speed selected by the driver unless a moving
obstacle proceeding directly ahead of it in the
same travel direction is detected (e.g.
following another vehicle ahead of you at your
set distance).
This means that:
R Your vehicle can pass another vehicle after
you have changed lanes.
R While in a sharp turn or if the preceding
vehicle is in a sharp turn, the DISTRONIC
PLUS could lose sight of the preceding
vehicle. Your vehicle could then accelerate
to the previously selected speed.
The DISTRONIC PLUS regulates only the
distance between your vehicle and those
directly ahead of it. It may not register
stationary objects in the road, e.g.:
R a stopped vehicle in a traffic jam
R a disabled vehicle
R an oncoming vehicle
The driver must always be alert, observe all
traffic and intercede as required by means of
steering or braking the vehicle.GWARNING
The DISTRONIC PLUS should not be used in
snowy or icy road conditions.
Cornering, going into and coming out of a
bend
The ability of DISTRONIC PLUS to detect
vehicles when cornering is limited. Your
vehicle may brake unexpectedly or late.
174Driving systemsDriving and parking
Activating the HOLD functionXMake sure that the activation conditions
are met.XDepress the brake pedal.XQuickly depress the brake pedal further
until HOLD display : appears in the
multifunction display.
The HOLD function is activated. You can
release the brake pedal.
i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.
GWARNING
The vehicle's brakes are applied when the
HOLD function is activated. For this reason,
deactivate the HOLD function if the vehicle is
to be set in motion by other means (e.g. in a
car wash or by towing).
Deactivating the HOLD function
The HOLD function is deactivated
automatically if:
R you accelerate and the transmission is in
position D or R.
R you shift the transmission to position P.
R you apply the brakes again with a certain
amount of pressure until HOLD disappears
from the multifunction display.
R you activate DISTRONIC PLUS.
GWARNING
Never get out of the vehicle when the HOLD
function is activated.
The HOLD function must never be operated
or deactivated by a passenger or from outside
the vehicle.
The HOLD function does not replace the
parking brake and must not be used for
parking.
The braking effect of the HOLD function is
canceled and the vehicle could roll away if:
R the HOLD function is deactivated by
depressing the accelerator pedal or the
brake pedal.
R there is a malfunction in the system or an
interruption in the power supply, e.g.
battery failure.
R the electrical system in the engine
compartment, the battery or the fuses are
tampered with.
R the battery is disconnected.
If you leave the vehicle or park it, deactivate
the HOLD function and secure the vehicle
against rolling away.
You will see a warning message in the
multifunction display if the HOLD function is
activated and:
R the driver's door is open and the driver's
seat belt is unfastened.
R the engine is switched off.
R the hood is opened.
Shift to 'P'XMove the selector lever to P to prevent the
vehicle from rolling away.
The HOLD function is deactivated. The
warning message in the multifunction
display disappears.
A horn will also sound at regular intervals if
the HOLD function is activated and you:
R switch the engine off, open the driver's
door and take off your seat belt
R open the hood
The sounding of the horn alerts you to the fact
that the vehicle has been parked while the
HOLD function is still activated. If you attempt
to lock the vehicle, the tone becomes louder.
The vehicle is not locked until the HOLD
function is deactivated.
Driving systems177Driving and parkingZ
Front sensorsCenterApproximately 40 in
(approximately 100 cm)CornersApproximately 24 in
(approximately 60 cm)
Rear sensors
CenterApproximately 48 in
(approximately 120 cm)CornersApproximately 32 in
(approximately 80 cm)
! 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.
Minimum distance
CenterApproximately 8 in
(approximately 20 cm)CornersApproximately 6 in
(approximately 15 cm)
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 air vents.
The warning display for the rear area in the
Coupe is located on the headliner in the rear
compartment; in the Cabriolet, it is between
the rear seats.
Warning display for the front area
: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
determines which warning display is active
when the engine is running.
Transmission
positionWarning displayDFront area activatedR or NRear and front areas
activatedPNo areas activatedDriving systems179Driving and parkingZ
When your speed exceeds approximately
20 mph (30 km/h), warning lamp : lights up
red on the corresponding side whenever a
vehicle is detected in the blind spot
monitoring range. This warning is always
given when a vehicle enters the blind spot
monitoring range from behind or from the
side. When you are passing another vehicle,
the warning is emitted only if the difference
in speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Active Blind
Spot Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.GWARNING
Active Blind Spot Assist is not active at speeds
lower than 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.
Visual and audible collision warnings
If you switch on the appropriate turn signals
and a vehicle is detected in the side
monitoring range, you will receive a visual and
acoustic collision warning. You will hear a
double warning tone and red warning
lamp : flashes. If the turn signal remains on,
vehicles detected are indicated by the
flashing of red warning lamp :. There are no
further warning tones.
Course-correcting brake application
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.
The course-correcting brake application is
available in the range between 20 mph
(30 km/h) and 120 mph (200 km/h).
If a course-correcting brake application
occurs, red warning lamp : flashes in the
exterior mirror and the following is shown in
the multifunction display, for example:GWARNING
Active Blind Spot Assist is only an aid
designed to assist driving. It is not a substitute
for attentive driving. In some cases, the
course-correcting brake application is not
sufficient to avoid a collision. In such a case,
you must steer, brake or accelerate.
In very rare cases, the system may
erroneously detect a danger of collision in the
area of crash barriers or similar lane borders
and apply the brakes. Active Blind Spot Assist
does not detect all traffic situations and road
users. Always make sure that there is
sufficient distance on the side for other traffic
or obstacles. An inappropriate brake
application may be interrupted at any time if
you steer slightly in the opposite direction or
accelerate.
You are responsible for 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,
you may fail to recognize dangers in time,
cause an accident and injure yourself and
others.
Driving systems191Driving and parkingZ
There will be either no or only a weak course-
correcting brake application 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 AssistXMake sure that the radar sensor system
( Y page 210) and Active Blind Spot Assist
( Y page 207) are activated in the on-board
computer.XTurn 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.
Active Lane Keeping Assist
Important safety 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.
:Active Lane Keeping Assist camera
If you have selected the Display Unit
Speed-/Odometer (Y page 208) function in
the on-board computer and select km as the
unit of measurement, Active Lane Keeping
Assist is active from speeds of 60 km/h. If
the miles display unit is selected, the
assistance range begins at 40 mph.
GWARNING
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 several or no lane markings for a single lane
are present.
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 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.
R the lane markings on the road are unclear,
e.g. near roadworks.
192Driving systemsDriving and parking