
Crossing vehicles
DISTRONIC PLUS may mistakenly detect
vehicles that are crossing your lane. Activat-
ing DISTRONIC PLUS at traffic lights with
crossing traffic, for example, could cause
your vehicle to pull away unintentionally.
HOLD function
General notes
The HOLD function can assist the driver in the
following situations: R when pulling away, especially on steep
slopes
R when maneuvering on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect is canceled and the HOLD
function deactivated when you depress the
accelerator pedal to pull away.
iDo not use the HOLD function when driv-
ing off-road, on steep uphill or downhill gra-
dients or on slippery or loose surfaces. The HOLD function cannot hold the vehicle on
such surfaces.
Important safety notes
GWARNING
When leaving the vehicle, it can still roll away despite being braked by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply.
R the HOLD function has been deactivated by
pressing the accelerator pedal or the brake
pedal, e.g. by a vehicle occupant.
R the electrical system in the engine com-
partment, the battery or the fuses have
been tampered with.
R the battery is disconnected
There is a risk of an accident.
If you wish to exit the vehicle, always turn off the HOLD function and secure the vehicle
against rolling away.
! If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations. To prevent dam-
age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow-
ing or other similar situations:
R when towing the vehicle
R in the car wash
Deactivating the HOLD function
( Y page 185).
Activation conditions
You can activate the HOLD function if:
R the vehicle is stationary
R the engine is running or if it has been auto-
matically switched off by the ECO start/
stop function
R the driver's door is closed or your seat belt
is fastened
R the parking brake is released
R the hood is closed.
R the transmission is in position D, R or N
R DISTRONIC PLUS is deactivated
184Driving systems
Driving and parking

Side view
Top view
Front sensors
CenterApprox. 40 in (approx.
100 cm)
CornersApprox. 24 in (approx.
60 cm)
Rear sensors
CenterApprox. 48 in (approx.
120 cm)
CornersApprox. 32 in (approx.
80 cm)
Minimum distance
CenterApprox. 8 in (approx.
20 cm)
CornersApprox. 6 in (approx.
15 cm)
If there is an obstacle within this range, the
relevant warning displays light up and a warn-ing 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 is loca-
ted on the headliner in the rear compartment.
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 vehi-
cle is divided into five yellow and two red seg- ments. PARKTRONIC is operational if yellow
segments showing operational readiness =
light up.
The selected transmission position and the
direction in which the vehicle is rolling deter-
mine which warning display is active when the engine is running.
Driving systems187
Driving and parking
Z

Transmission
positionWarning display
DFront area activated
R, N or the vehicle
is rolling back-
wardsRear 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:
R sixth segment onwards, you will hear an
intermittent warning tone for approx-
imately two seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two sec-
onds. This indicates that you have now
reached the minimum distance.
Deactivating/activating PARKTRONIC
:Deactivating/activating PARKTRONIC
;Indicator lamp
If indicator lamp ; lights up, PARKTRONIC is
deactivated.
iPARKTRONIC is automatically activated
when you turn the SmartKey to position 2 in
the ignition lock.
Towing a trailer
! Fold in the ball coupling if the trailer tow
hitch is not required. PARKTRONIC meas-
ures the minimum detection range to an
obstacle from the bumper, not the ball cou- pling.
PARKTRONIC is deactivated for the rear area
when you establish an electrical connection
between your vehicle and a trailer.
188Driving systems
Driving and parking

Problems with PARKTRONIC
ProblemPossible causes/consequences and M Solutions
Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp
in the PARKTRONIC
button lights up.PARKTRONIC has malfunctioned and has switched off.
X If problems persist, have PARKTRONIC checked at a qualified
specialist workshop.
Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is deacti-
vated after approx-
imately five seconds.The PARKTRONIC sensors are dirty or there is interference. X Clean the PARKTRONIC sensors ( Y page 309).
X Switch the ignition back on.
The problem may be caused by an external source of radio or
ultrasound waves. XSee if PARKTRONIC functions in a different location.
Active Parking Assist
Important safety notes
Active Parking Assist is an electronic parking
aid with ultrasound. Ultrasound is used to
measure the road on both sides of the vehicle. A parking symbol indicates a suitable parking
space. Active steering intervention can assist you during parking. You may also use
PARKTRONIC ( Y page 186).
GWARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
result in a collision with another road user.
There is a risk of an accident.
Pay attention to other road users. Stop the
vehicle if necessary or cancel the Active Park-
ing Assist parking procedure.
! If unavoidable, you should drive over
obstacles such as curbs slowly and not at a sharp angle. Otherwise, you may damage
the wheels or tires.
Active Parking Assist is merely 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. Make sure that
no persons, animals or objects are in the
maneuvering range.
When PARKTRONIC is switched off, Active
Parking Assist is also unavailable.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for
parking, for example:
R where parking or stopping is prohibited
R in front of driveways or entrances and exits
R on unsuitable surfaces
Driving systems189
Driving and parking
Z

then have to steer and merge into traffic on
your own. PARKTRONIC is still available.
Canceling Active Parking Assist
You can cancel Active Parking Assist at any
time.
X Stop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at
once. The
Park Assist Canceled mes-
sage appears in the multifunction display.
or
X Press the PARKTRONIC button on the cen-
ter console ( Y page 188).
PARKTRONIC is switched off and Active
Parking Assist is immediately canceled.
The
Park Assist Canceled message
appears in the multifunction display.
Active Parking Assist is canceled automati-
cally if: R transmission position P is selected
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, ESP ®
intervenes or fails. The
÷ warning lamp lights up in the instru-
ment cluster.
A warning tone sounds. The parking symbol
goes out and the
Park Assist Canceled
message appears in the multifunction dis-
play.
If Active Parking Assist is canceled, you must
steer again yourself.
Towing a trailer
For vehicles with a trailer tow hitch, the min-
imum length for parking spaces is slightly
increased.
If you have attached a trailer to your vehicle,
you should not use Active Parking Assist.
Once the electrical connection is established between your vehicle and the trailer, Active
Parking Assist is no longer available.
PARKTRONIC is deactivated for the rear area.
Rear view camera
General notes
:Rear view camera
Rear view camera : is located in the handle
strip of the tailgate.
Rear view camera : is an optical parking and
maneuvering aid. It uses guide lines to show
the area behind your vehicle in the Audio/
COMAND display.
The area behind the vehicle is displayed as a
mirror image, as in the rear view mirror.
iThe text of messages shown in the
COMAND display depends on the language
setting. The following are examples of rear view camera messages in the COMAND
display.
Important safety notes
The rear view camera is only an aid. It is not a
replacement for your attention to your imme- diate surroundings. You are always responsi-
ble for safe maneuvering and parking. When
maneuvering or parking, make sure that there are no persons, animals or objects in the area
in which you are maneuvering.
Under the following circumstances, the rear
view camera will not function, or will function
in a limited manner:
R if the tailgate is open
R in heavy rain, snow or fog
R at night or in very dark places
R if the camera is exposed to very bright light
Driving systems193
Driving and parking
Z

AYellow guide line at a distance of approx-
imately 3 ft (1.0 m) from the rear of the
vehicle
BVehicle center axle (marker assistance)
CBumper
DRed guide line at a distance of approx-
imately 12 in (0.30 m) from the rear of thevehicle
The guide lines are shown when the trans-
mission is in position R.
The distance specifications only apply to
objects that are at ground level.
Additional messages for vehicles with
PARKTRONIC :
Front warning display
;Additional PARKTRONIC measurement
operational readiness indicator
=Rear warning display
Vehicles with PARKTRONIC: if
PARKTRONIC is operational ( Y page 187), an
additional operational readiness indicator will
appear in COMAND display ;. If the
PARKTRONIC warning displays are active or
light up, warning displays : and = are also active or light up correspondingly in the
COMAND display.
"Reverse parking" function
X
Make sure that the rear view camera is
activated and the "Reverse parking" func-
tion is selected; see the separate operating
instructions for the audio system/
COMAND.
The lane and the guide lines are shown.
Backing up straight into a parking space
without turning the steering wheel
:White guide line without turning the steer-
ing wheel, vehicle width including the
exterior mirrors (static)
;Red guide line for the vehicle width includ-
ing the exterior mirrors, for current steer-
ing wheel angle (dynamic)
=Yellow guide line at a distance of approx-
imately 3 ft (1.0 m) from the rear of the
vehicle
?Red guide line at a distance of approx-
imately 12 in (0.30 m) from the rear of the
vehicle
Driving systems195
Driving and parking
Z

Display with the PARKTRONIC display
Example: full screen mode with PARKTRONIC dis-
play :
Symbol for the full screen setting with rear
view camera image
If the vehicle is equipped with PARKTRONIC
and the function is active ( Y page 188), warn-
ing displays ; in the COMAND display are
also active or light up accordingly.
PARKTRONIC appears:
R in split screen view as red or yellow brack-
ets around the vehicle icon in the top view, or
R in the full screen view, on the right-hand
side at the bottom as red or yellow brackets
around the vehicle icon
iThe full screen display can also be selec-
ted as front view.
Exiting 360° camera display mode
As soon as your vehicle exceeds a speed of
19 mph (30 km/h) with the function activa-
ted, the function switches off. The COMAND
display switches back to the previously selec- ted view. You can also switch the display by
selecting the & symbol in the display and
pressing W the COMAND controller.
ATTENTION ASSIST
Important safety notes
ATTENTION ASSIST is only an aid to the
driver. It might not always recognize fatigue or increasing inattentiveness in time or fail to
recognize them at all. The system is not a
substitute for a well-rested and attentive
driver.
ATTENTION ASSIST helps you during long,
monotonous journeys, such as on highways.
It is active in the range between 50 mph
(80 km/h) and 112 mph (180 km/h).
If ATTENTION ASSIST detects typical indica-
tors of fatigue or increasing lapses in con-
centration on the part of the driver, it sug-
gests you take a break.
ATTENTION ASSIST assesses your level of
fatigue or lapses in concentration by taking
the following criteria into account: R your personal driving style, e.g. steering
characteristics
R journey details, e.g. time of day and length
of journey
The functionality of ATTENTION ASSIST is
restricted and warnings may be delayed or
not occur at all:
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 slower
than 50 mph (80 km/h) or faster than
112 mph (180 km/h)
R if you are currently using COMAND or mak-
ing a telephone call with it
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
Warning and display messages in the
multifunction display
XActivate ATTENTION ASSIST using the on-
board computer ( Y page 229).
If ATTENTION ASSIST is active, you will be
warned no sooner than 20 minutes after your journey has begun. You then hear an inter-
202Driving systems
Driving and parking

Ryou are not driving in the middle of the lane
R there are barriers or similar lane borders
Vehicles in the monitoring range are then not indicated.
Blind Spot Assist monitors the area up to 10 ft
(3 m) behind your vehicle and directly next toyour vehicle, as shown in the diagram.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may
be indicated, especially if the vehicles are not
driving in the middle of their lane. This may be the case if there are vehicles driving at the
inner edge of their lanes.
Due to the nature of the system:
R warnings may be issued in error when driv-
ing close to crash barriers or similar solid
lane borders.
R the warning is canceled when driving for an
extended period next to long vehicles, such
as trucks.
The two radar sensors for Blind Spot Assist
are integrated into the sides of the rear
bumper. Make sure that the bumper is free of dirt, ice or slush in the vicinity of the sensors.
The sensors must not be covered, for exam-
ple by cycle racks or overhanging loads. Fol-
lowing a severe impact or in the event of dam- age to the bumpers, have the function of the
sensors checked at a qualified specialist workshop. Blind Spot Assist may otherwise
not work properly.
Indicator and warning display
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in the monitoring range are then not indicated.
:Yellow indicator lamp/red warning lamp
When Blind Spot Assist is activated, indicator
lamp : in the exterior mirrors lights up yel-
low at speeds of up to 20 mph (30 km/h). At speeds above 20 mph (30 km/h), the indica-
tor lamp goes out and Blind Spot Assist is
operational.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp : on the corre-
sponding 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 (12 km/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, vehicles detected
204Driving systems
Driving and parking