
Conditions for activation
RACE START can be activated when:
R the doors are closed.
R the engine is running and it has reached an
operating temperature of approximately
80 †. This is the case when the engine oil
temperature in the multifunction display
stops flashing.
R SPORT handling mode is activated.
(Y page 69)
R the steering wheel is in the straight-ahead
position.
R the vehicle is stationary and the brake
pedal is depressed (lef tfoot).
R the transmission is in position D.
Activating RACE START X
Depress the brake pedal with your left foot,
and keep it depressed.
X Turn the drive program selector clockwise
(Y page 147) until the RSlamp lights up.
The multifunction display shows the RACESTART Confirm: Paddle UP Cancel:
Paddle DOWN message.
i If the conditions for activation are no lon-
ger fulfilled, RACE START is cancelled. The
multifunction display shows the RACESTART cancelled message.
X To cancel: pull the left steering wheel shift
paddle (Y page 148).
or
X To confirm: pull the right steering wheel
shift paddle (Y page 148).
The multifunction display shows the RACESTART available Depress accelera‐
tor message.
i If you do not depress the accelerator
pedal fully within two seconds, RACE
START is cancelled. The multifunction dis-
play shows the RACE START not possi‐ ble See Owner's Manual message.X
Depress the accelerator pedal fully.
The engine speed rises to approximately
4000 rpm.
The multifunction display shows the RACE START Release brake to start mes-
sage.
i If you do not release the brake pedal
within seven seconds, RACE START is can-
celled. The multifunction display shows the
RACE START cancelled message.
X Take your foot off the brake, but keep the
accelerator pedal depressed.
The vehicle pulls away at maximum accel-
eration.
The multifunction display shows the RACE START active message.
RACE START is deactivated when the vehicle
reaches a speed of approximately 50 km/h.
Drive program S+is activated. SPORT han-
dling mode remains activated.
RACE START is deactivated immediately if
you release the accelerator pedal during
RACE START or if any of the activation condi-
tions are no longer fulfilled. The multifunction
display shows the RACE START not possi‐ ble See Owner's Manual message.
i If RACE START is used repeatedly in a
short period of time, it is only available
again after having driven the vehicle a cer-
tain distance. PARKTRONIC
Important safety notes G
WARNING
PARKTRONIC is only an aid and may not
detect all obstacles. It is not a substitute for
attentive driving.
You are always responsible for safety and
must continue to pay attention to your imme-
diate surroundings when parking and
manoeuvring. You could otherwise endanger
yourself and others. Driving systems
179Driving and parking Z

Problems with PARKTRONIC
Problem Possible 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 20 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 20 seconds. The PARKTRONIC sensors are dirty or there is interference.
X
Cleant he 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.
X See if PARKTRONIC functions in a different location. Parking Guidance
Important safety notes Parking Guidance is an electronic parking aid
with ultrasound. Ultrasound is used to meas-
ure the road on both sides of the vehicle. A
suitable parking space is indicated by the
parking symbol. You receive steering instruc-
tions when parking. You may also use PARK-
TRONIC (Y page 179). G
WARNING
Parking Guidance is merely an aid and may
recommend parking spaces that are not suit-
able for parking. For example, these might be
spaces where parking is prohibited, drive-
ways, unsuitable surfaces, etc.
Parking Guidance measures the parking
space as you drive past it. Any later changes
to the parking space are not taken into
account. For instance, this may be the case when the vehicle parked in front of or behind
the space changes its position or when an
obstacle is moved into the parking space.
Parking Guidance does not relieve you of the
responsibility for paying attention. If you rely
solely on Parking Guidance, you could cause
an accident and injure yourself and others.
You are always responsible for safety and
must continue to pay attention to your imme-
diate surroundings when parking and
manoeuvring.
G
WARNING
Objects located above the height range of
Parking Guidance will not be detected when
the parking space is measured. These are not
taken into account when the parking proce-
dure is calculated, e.g. overhanging loads, tail
sections or loading ramps of goods vehicles.
In some circumstances, Parking Guidance Driving systems
183Driving and parking
Z

might therefore issue steering instructions
too soon. This may lead to a collision. For this
reason, you should avoid using Parking Guid-
ance in such situations. G
WARNING
Make sure that no persons or animals are in
the manoeuvring range. Otherwise, they
could be injured.
When PARKTRONIC is deactivated, Parking
Guidance is also unavailable.
Use Parking Guidance for parking spaces:
R that are parallel to the directio noftravel
R that are on straight roads, not bends
R that are on the same level as the road, i.e.
not on the pavement, for example. Parking
Guidance may not detect flat kerbs
Parking tips:
R on narrow roads, drive pastt he parking
space as close as possible.
R parking spaces that are littered, overgrown
or partially occupied by trailer drawbars
might be identified incorrectly or not at all.
R snowfall or heavy rain may lead to a parking
space being measured inaccurately.
R pay attention to the PARKTRONIC
(Y page 181) warning messages during the
parking procedure.
R when transporting a load which protrudes
from your vehicle, you must not use Parking
Guidance.
R never use Parking Guidance with snow
chains or an emergency spare wheel fitted.
R make sure that the tyre pressures are
always correct.T his hasadirec teffect on
the steering instructions.
R the way you rvehicle is positioned in the
parking space after parkin gis dependent
on various factors. These include the posi-
tion and shape of the vehicles parked in
front and behind it and the conditions of the
location. In some cases, Parking Guidance
may guide you too far or not far enough into
a parking space. In some cases, it may also lead you across or onto the kerb. If neces-
sary, cancel the parking procedure with
Parking Guidance.
! If unavoidable, you should drive over
obstacles such as kerbs slowly and not at
a sharp angle. Otherwise, you may damage
the wheels or tyres.
Detecting parking spaces Example: vehicles with automatic transmission
:
Detected parking space on the left
; Parking symbol
= Detected parking space on the right
Parking Guidance is automatically activated
when you drive forwards. The system is
operational at speeds of up to approximately
35 km/h. While in operation, the system inde-
pendently locates and measures parking
spaces on both sides of the vehicle. When
driving at speeds below 30 km/h, you will see
parking symbol ;as a status indicator in the
instrument cluster.
When a parking space has been detected, an
arrow towards the right =or the left :also
appears. Parking Guidance only displays
parking spaces on the front-passenger side
as standard. Parking spaces on the driver's
side are displayed as soon as the turn signal
on the driver's side is activated. To park on
the driver's side, you must leave the driver's
side turn signal switched on until you have
engaged reverse gear. 184
Driving systemsDriving and parking

Parking Guidance will only detect parking
spaces:
R that are parallel to the direction of travel
R that are at least 1.5 m wide
R that are at least 1.3 m longer than your
vehicle
Ap arking space is displayed while you are
driving past it, and until you are approx-
imately 15 m away from it.
Parking G
WARNING
PARKTRONIC and Parking Guidance are
merely parking aids and may no tdetec tall
obstacles. They do not relieve you of the
responsibility of paying attention.
You are always responsible for safety and
must continue to pay attention to your imme-
diate surroundings when parking and
manoeuvring. You could otherwise endanger
yourself and others.
X Stop the vehicle when the parking space
symbol shows the desired parking space in
the instrument cluster.
X Vehicles with manual transmission :shift to
reverse gear.
Vehicles with automatic transmission: shift
into position R.
The following message appears in the mul-
tifunction display: Check vehicle sur‐ roundings Confirm with OK .
X Press the abutton on the multifunction
steering wheel to confirm.
The multifunction display switches to Park-
ing Guidance.
Depending on your distance from the park-
ing space, the Please drive backwards
message appears in the multifunction dis-
play. Example: vehicles with automatic transmission
X
If necessary, reverse towards the parking
space. This is indicated by an arrow point-
ing backwards.
Continue reversing until you hear a tone.
Stop –the parking position has been
reached. The arrow is white.
The Please steer to the right or
Please steer to the left message
appears in the multifunction display. Example: vehicles with automatic transmission
X
While the vehicle is stationary, turn the
steering wheel in the specified direction
until the arrow is white and a warning tone
sounds.
X To reverse into the parking space: main-
tain the steering wheel angle and reverse
carefully.
X Stop as soon as you hear a warning tone,
The vehicle has reached the position in
which you need to countersteer.
The Please steer to the left or
Please steer to the right message
appears in the multifunction display.
X Countersteering: while the vehicle is sta-
tionary, turn the steering wheel in the
specified direction until the arrow is white
and a warning tone sounds. Driving systems
185Driving and parking Z

X
To reverse into the parking space: main-
tai nt he steering wheel angle and reverse
carefully.
X Stop as soon as you hear a warning tone,
at the latest when PARKTRONIC sounds the
continuous warning tone.
The Parking Guidance finished mes-
sage appears in the multifunction display
and a warning tone sounds. You may be
asked to steer in adifferent direction and
the nchange gear. In this case, further dis-
plays in the multifunction display will direct
you to the final position.
X Manoeuvre if necessary.
X Always observe the warning messages dis-
played by PARKTRONIC (Y page 181).
Cancelling Parking Guidance X
Press the PARKTRONIC button on the
centre console (Y page 182).
Parking Guidance is cancelled immediately
and PARKTRONIC is deactivated.
Parking Guidance is cancelled automatically
if it is no longer possible to guide you into the
parking space, or if a malfunction occurs.
The parking space symbol goes out and a
warning tone sounds. The Parking Guid‐ance cancelled message appears in the
multifunction display.
Trailer towing 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 Parking Guidance. When
the electrical connection is established
between your vehicle and the trailer, Parking
Guidance ceases to be available. PARK-
TRONIC is deactivated for the rear area. Reversing camera
Important safety notes The reversing camera is an optical parking
aid. It shows the area behind your vehicle in
the COMAND Online display.
G
WARNING
Make sure that no persons or animals are in
the manoeuvring range. Otherwise, they
could be injured.
The reversing camera is located in the handle
strip of the boot lid. :
Reversing camera
View through the camera The area behind the vehicle is displayed as a
mirror image, as in the rear-view mirror.
G
WARNING
The reversing camera is only an aid and may
display obstacles in a distorted or incorrect
manner, or may not even display them at all.
The reversing camera does not relieve you of
the responsibility to pay attention. The cam-
era cannot show objects:
R very near to the rear bumper
R below the rear bumper
R in the area immediately above the boot lid
handle
You are always responsible for safety and
must continue to pay attention to your imme-
diate surroundings when parking and
manoeuvring. This applies to the areas 186
Driving systemsDriving and parking

Guide lines
;and =show the approximate
distance to the rear area. Yellow guide
line ;indicates a distance of approximately
1. 0ma nd red guide line =indicates a dis-
tance of approximately 0.25 m. The distances
only apply to objects tha tare at ground level.
Blue guide lines :depict the width required
for the vehicle. They are used to align the
vehicle with the edge of the carriageway, e.g.
the kerb. ATTENTION ASSIST
Important safety notes ATTENTION ASSIST helps you during long,
monotonous journeys such as on motorways
and trunk roads. It is active in the 80 km/h
to 180 km/h range.
If ATTENTION ASSIST detects typical indica-
tors of fatigue or increasing lapses in con-
centration on the part of the driver, it sug-
gests taking a break. G
WARNING
ATTENTION ASSIST is only an aid and may
detect yourt iredness or lapses in concentra-
tion too late or not at all. It is not asubstitute
for a well rested and attentive driver.
Fatigue may cause you to recognise hazard-
ous situations too late, misjudge a situation
or react slower. For this reason, make sure
you feel rested before you begin driving and
during your journey. Always take breaks in
good time and regularly, especially during
long journeys. Otherwise, you may fail to rec-
ognise dangers in time, cause an acciden tand
injure yoursel fand others.
ATTENTIO NASSIST 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 driving conditions, e.g. time, driving time 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 sid ewind
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 80 km/h or faster than 180 km/h
R if you are currently using COMAND Online
or making 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 Example: vehicles with automatic transmission
X
Activate ATTENTION ASSIST using the on-
board computer (Y page 222).
Symbol :appears in the multifunction
display.
If ATTENTION ASSIST is active, you will be
warned no sooner than 20 minutes after your
journey has begun. You will the nhear an
intermittent warning tonet wice, and the
Attention Assist: Drowsiness detec‐ ted message appears in the multifunction
display.
X If necessary, take a break.
X Press the abutton to confirm th emes-
sage.
On long journeys, take regular breaks in good
time to allow yourself to rest properly. If you
do not take a break and ATTENTION ASSIST 188
Driving systemsDriving and parking

If the
miles display unit is selected, the assis-
tance range begins at 40 mph. G
WARNING
Lane Keeping Assist does not keep yourv ehi-
cle 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 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.
R the windscreen is dirty, misted up or cov-
ered, for instance by a sticker, in the vicinity
of the camera
R several or no lane markings for a single lane
are present.
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.
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge.
R the road is narrow and winding.
Lane Keeping Assist cannot detect road and
traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, 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 recognise dangers in time,
cause an acciden tand injure yoursel fand oth-
ers.
A warning may be given if a front wheel
passes ove ralane marking. It will warn you by means of intermittent vibration in the
steering wheel for up to 1.
5seconds.
In order that you are warned only when nec-
essary and in good time if you cross the lane
marking, the system recognises certain con-
ditions 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, e.g. a motor-
way.
R the system recognises solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.
No warning vibration occurs if:
R you clearly and actively steer, brake, or
accelerate.
R you cut the corner on a sharp bend.
R a driving safety system intervenes, such as
ABS, BAS or ESP ®
.
R you have switched on the turn signals. In
this event, the warnings are suppressed for
a certain period of time.
Activating Lane Keeping Assist Example: vehicles with automatic transmission
X
Activate Lane Keeping Assist using the on-
board computer (Y page 222).
Symbol :appears in the multifunction
display.
If you drive at speeds above 60 km/h and
lane markings are detected, symbol :is
displayed in green. Lane Keeping Assist is
ready for use. Driving systems
193Driving and parking Z

Active Driving Assistance package
General notes The Active Driving Assistance package con-
sists of DISTRONIC PLU
S(Ypage 164), Active
Blind Spot Assist (Y page 194) and Active
Lane Keeping Assist (Y page 197).
Active Blind Spot Assist Important safety notes
Active Blind Spot Assist uses a radar sensor
system to monitor the side areas of your vehi-
cle that are behind the driver. Awarning dis-
play in the exterior mirrors draws your atten-
tio nt o detected vehicles in the monitored
area. If you then switch on the corresponding
turn signal to change lane, you will also
receive a visual and acoustic collision warn-
ing. If a risk of lateral collision is detected,
corrective braking may help you avoid a col-
lision. To support the course-correcting brake
application, Active Blind Spot Assist also uses
the forward-facing radar sensor system.
Active Blind Spot Assist provides assistance
at speeds higher than about 30 km/h. G
WARNING
Active Blind Spot Assist is only an aid and may
detect vehicles/obstacles incorrectly or not
at all.
The system may be impaired or may not func-
tion if:
R there is poor visibility, e.g. due to snow,
rain, fog or spray.
R the rear and/or front sensors are dirty.
Active Blind Spot Assist may not detect nar-
row vehicles, such as motorcycles or bicycles,
or only detect them too late. It cannot detect
vehicles which are overtaken at a small dis-
tance and then enter the blind spot area.
Active Blind Spot Assist cannot detect road
and traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, 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 recognise dangers in time,
cause an accident and injure yourself and oth-
ers.
The radar sensor system is automatically
deactivated near radio telescope facilities
(Y page 363).
For Active Blind Spot Assist to assist you
when driving, the radar sensor system must
be activated (Y page 226) and operational.
Monitoring range
Active Blind Spot Assist monitors the area up
to three metres behind your vehicle and
directly next to your vehicle, as shown in the
diagram. For this purpose, Active Blind Spot
Assist uses radar sensors in the rear bumper. G
WARNING
Active Blind Spot Assist monitors certain
areas in the immediate vicinity of your vehicle.
Vehicles that approach and drive past at high
speeds are not detected. No visual nor audi-
ble warnings are emitted and the system does
not brake the vehicle to correct your course.
If the lanes are very wide, it may not be pos-
sible to monitor the complete width of the
neighbouring lane. For this reason, vehicles in 194
Driving systemsDriving and parking