Continue todrive carefully and beready to
brake, inparticular when warned to dosoby
DI ST RONIC PLU S.
GWARNING
DI ST RONIC PLUS brakes your veh icle 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.
!When DISTRONIC PLUS or the HOLD func-
tion is activated, the vehicle brakes automat-
ically in certain situations.
To avoid damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or similar situations:
Rwhen towing the vehicle
Rin the car wash
DISTRONIC PLUS can neither reduce the risk of
an accident if you fail to adapt your driving style
nor override the laws of physics. DISTRONIC
PLUS cannot take account of road, weather and traffic conditions. DISTRONIC PLUS is only an
aid. You are responsible for maintaining a safe
distance to the vehicle in front, for vehicle
speed, for braking in good time and for staying in
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 accel-
erating 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 vehi-
cles driving in front, e.g. motorcycles, or vehi-
cles driving on a different line.
In particular, the detection of obstacles can be
impaired if:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is snow or heavy rain
Rthere is interference by other radar sources
Rthere are strong radar reflections, for exam-
ple, in parking garages
If DISTR
ONIC 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 in the right lane that you pass vehi-cles driving on the left (left-hand drive coun-
tries)
Rbe so high in the left lane that you pass vehi-
cles driving on the right (right-hand drive
countries)
If there is a change of drivers, advise the new
driver of the speed stored.
Cruise control lever
0043Activates or increases speed
0044Activates or reduces speed
0087Deactivates DISTRONIC PLUS
0085Activates at the current speed/last stored
speed
0083Sets a specified minimum distance
Activating DISTRONIC PLUS
Activation conditions
To activate DISTRONIC PLUS, the following con-
ditions must be fulfilled:
Rthe engine must be started. It may take up to two minutes after pulling away before
DISTRONIC PLUS is operational.
Rthe electric parking brake must be released.
RESP®must be activated, but not intervening
at present.
RActive Parking Assist must not be activated.
148Driving systems
Driving and parking
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 position D,Ror N
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h). It is reactivated at lower
speeds.
Range of the sensors
PARKTRONIC does not take objects into con-
sideration that are:
Rbelow the detection range, e.g. people, ani-
mals or objects.
Rabove the detection range, e.g. overhanging
loads, truck overhangs or loading ramps.
0043Sensors in the front bumper, left-hand side
(example)
0043Approx. 24 in (approx. 60 cm) (corners)
0044Approx. 32 in (approx. 80 cm) (corners)
0087Approx. 48 in (approx. 120 cm) (center)
0085Approx. 40 in (approx. 100 cm) (center)
The sensors must be free from dirt, ice or slush.
They can otherwise not function correctly. Clean
the sensors regularly, taking care not to scratch
or damage them (
Ypage 284).
Minimum distance
CenterApprox. 8 in (approx. 20 cm)
CornersApprox. 6 in (approx. 15 cm)
If there is an obstacle within this range, the rel-
evant warning displays light up and a warning
tone sounds. If the distance falls below the min-
imum, the distance may no longer be shown.
Driving systems161
Driving and parking
Z
Problems with PARKTRONIC
ProblemPossible causes/consequences and0050Solutions
Only the red segments in
the PARKTRONIC warn-
ing displays are lit. You
also hear a warning tone
for approximately two
seconds.
PARKTRONIC is then
deactivated and the indi-
cator lamp on the
PARKTRONIC button
lights up.PARKTRONIC has malfunctioned and has switched off.
XIf problems persist, have PARKTRONIC checked at a qualified spe-
cialist workshop.
Only the red segments in
the PARKTRONIC warn-
ing displays are lit.
PARKTRONIC is then
deactivated.The PARKTRONIC sensors are dirty or there is interference.
XClean the PARKTRONIC sensors (Ypage 284).
XSwitch the ignition back on.
The problem may be caused by an external source of radio or ultra-
sound waves.
XSee if PARKTRONIC functions in a different location.
Active Parking Assist
General notes
Active Parking Assist is an electronic parking aid
with ultrasound. It measures the road on both
sides of the vehicle. A parking symbol indicates a suitable parking space. Active steering inter-
vention and brake application can assist you
during parking and when exiting a parking
space. You may also use PARKTRONIC
(
Ypage 160).
Important safety notes
Active Parking Assist is merely an aid. It is not a
replacement for your attention to your immedi-
ate surroundings. You are always responsible
for safe maneuvering, parking and exiting a
parking space. Make sure that no persons, ani-
mals or objects are in the maneuvering range.
When PARKTRONIC is switched off, Active Park-
ing Assist is also unavailable.
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 obsta-
cles such as curbs slowly and not at a sharp
angle. Otherwise, you may damage the
wheels or tires.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for park-
ing, for example:
Rwhere parking or stopping is prohibited
Rin front of driveways or entrances and exits
Ron unsuitable surfaces
Parking tips:
ROn narrow roads, drive as close to the parking
space as possible.
RParking spaces that are littered or overgrown
might be identified or measured incorrectly.
RParking spaces that are partially occupied by
trailer drawbars might not be identified as
such or be measured incorrectly.
Driving systems163
Driving and parking
Z
sion is detected, corrective braking may help
you avoid a collision. Before a course-correcting
brake application, Active Blind Spot Assist eval-
uates the space in the direction of travel and at
the sides of the vehicle. For this, Active Blind
Spot Assist uses the forward-facing radar sen-
sors.
Active Blind Spot Assist supports you from a
speed of approximately 20 mph (30 km/h).
Important safety notes
Active Blind Spot Assist is only an aid and is not
a substitute for attentive driving.
GWARNING
Active Blind Spot Assist does not react to:
Rvehicles overtaken too closely on the side,
placing them in the blind spot area
Rvehicles which approach with a large speed
differential and overtake your vehicle
As a result, Active Blind Spot Assist may nei-
ther give warnings nor intervene in such sit-
uations. There is a risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
iUSA only: This device has been approved by
the FCC as a "Vehicular Radar System". The
radar sensor is intended for use in an auto-
motive radar system only. Removal, tamper-
ing, or altering of the device will void any war-
ranties, and is not permitted by the FCC. Do
not tamper with, alter, or use in any non-
approved way.
Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
iCanada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause harmful inter-
ference, and
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the device
will void any warranties, and is not permitted. Do not tamper with, alter, or use in any non-
approved way. Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
Radar sensors
The Active Blind Spot Assist radar sensors are
integrated into the front and rear bumpers and
behind a cover in the radiator trim. Make sure
that the bumpers and the cover in the radiator
grill are free of dirt, ice or slush. The rear sensors
must not be covered, for example by cycle racks
or overhanging cargo. Following a severe impact
or in the event of damage to the bumpers, have
the function of the radar sensors checked at a
qualified specialist workshop. Active Blind Spot
Assist may otherwise no longer work properly.
Monitoring area
GWARNING
Active Blind Spot Assist does not detect all
traffic situations and road users. There is a
risk of an accident.
Always make sure that there is sufficient dis-
tance on the side for other traffic or obstacles.
At a distance of approximately 1.6 ft (0.5 m)0044
from the vehicle, Active Blind Spot Assist mon-
itors the area up to 10 ft (3 m) next to 0087and
behind 0043your vehicle, as shown in the picture.
The detection of obstacles can be impaired in
the case of:
Rthere is dirt on the sensors or anything else
covering the sensors
Rpoor visibility, e.g. due to rain, snow or spray
Driving systems181
Driving and parking
Z
The course-correcting brake application is avail-
able in the speed range between 20 mph
(30 km/h) and 120 mph (200 km/h).
Either no braking application, or a course-cor-
recting brake application adapted to the drivingsituation occurs if:
Rthere are vehicles or obstacles, e.g. crash
barriers, located on both sides of your vehicle.
Ra vehicle approaches you too closely at the
side.
Ryou have adopted a sporty driving style with
high cornering speeds.
Ryou clearly brake or accelerate.
Ra driving safety system intervenes, e.g. ESP®
or PRE-SAFE®Brake.
RESP®is switched off.
Ra loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist
XMake sure that Active Blind Spot Assist is
activated in the on-board computer
(
Ypage 199)
XSwitch on the ignition.
Warning lamps in the exterior mirrors light up
red for approximately 1.5 seconds. Gray radarwaves propagating backwards appear next to
the vehicle in the assistance display on the
multifunction display.
Active Lane Keeping Assist
General notes
Active Lane Keeping Assist monitors the area in
front of your vehicle by means of multifunction
camera 0043at the top of the windshield. Various
different areas to the front, rear and side of your
vehicle are also monitored with the aid of the
radar sensor system. Active Lane Keeping Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally. If you do not react to the warning, a
lane-correcting application of the brakes can
bring the vehicle back into the original lane.
This function is available in a speed range
between 40 mph and 120 mph (60 km/h and
200 km/h)
.
Important safety notes
Ifyou fail to adapt your driving style, Active Lane
Keeping Assist can neither reduce the risk of an accident nor override the laws of physics. Active
Lane Keeping Assist cannot take account of
road and weather conditions. It may not recog-
nize traff icsituations. Active Lane Keeping
Assist isonly an aid. You are responsible for the
distance to the vehicle infront, for vehicle
speed, for braking ingood time and for staying in
your lane.
Active Lane Keeping Assist cannot continuously
keep your vehicle inits lane.
GWARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings.
In such cases, Active Lane Keeping Assist
can:
Rgive an unnecessary warning and then
make a course-correcting brake application
to the vehicle
Rnot give a warning or intervene
There isa risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Active Lane Keeping Assist alerts you. Ter-
minate the intervention ina non-critical driv-
ing situation.
The system may be impaired or may not function
if:
Rthere is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,
fog or spray
Rthere is glare, e.g. from oncoming traffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet)
Rthe windshield isdirty, fogged up, damaged or
covered, for instance bya sticker, in the vicin-
ity of the camera
Driving systems183
Driving and parking
Z
Rthe radar sensors in the front or rear bumpers
or the radiator trim are dirty, e.g. obscured by
snow
Rthere are no, several or unclear lane markings
for a lane, e.g. in areas with road construction
work
Rthe lane markings are worn away, dark or cov-
ered up, e.g. by dirt or snow
Rthe distance to the vehicle in front is too small
and the lane markings thus cannot be detec-
ted
Rthe lane markings change quickly, e.g. lanes
branch off, cross one another or merge
Rthe road is narrow and winding
Rthere are strong shadows cast on the road
If no vehicle is detected in the adjacent lane and
broken lane markings are detected, no lane-cor-
recting brake application is made.
Warning vibration in the steering wheel
A warning may be given if a front wheel passes
over a lane marking. It will warn you by means of
intermittent vibration in the steering wheel for
up to 1.5 second s.
In orde r that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, the system recognizes certain conditions
and warns you accordingly.
The warning vibration occurs earlier if:
Ryou approach the outer lane marking on a
bend.
Rthe road has very wide lanes, e.g. a highway.
Rthe system recognizes solid lane markings.
The warning vibration occurs later if:
Rthe road has narrow lanes.
Ryou cut the corner on a bend.
Lane-correcting brake application
If you leave your lane, under certain circumstan-
ces the vehicle will brake briefly on one side.
This is meant to assist you in bringing the vehicle
back to the original lane.
GWARNING
A lane-correcting brake application cannot
always bring the vehicle back into the original lane. There is a risk of an accident.
Always steer, brake or accelerate yourself,
especially if Active Lane Keeping Assist warns
you or makes a lane-correcting brake appli-
cation.
GWARNING
Active Lane Keeping Assist does not detect
traffic conditions or road users. In very rare
cases, the system may make an inappropriate brake application, e.g. after intentionally driv-
ing over a solid lane marking. There is a risk of
an accident.
An inappropriate brake application may be
interrupted at any time if you steer slightly in
the opposite direction. Always make sure that
there is sufficient distance on the side for
other traffic or obstacles.
If a lane-correcting brake application occurs,
display 0043appears in the multifunction display.
The brake application also slightly reduces vehi-
cle speed.
A lane-correcting brake application can be made
after driving over a lane marking recognize as
being solid or broken. Before this, a warning
must be given by means of intermittent vibration
in the steering wheel. In addition, a lane with
lane markings on both sides must be detected.
In the case of a broken lane marking being
detected, a lane-correcting brake application
can only be made if a vehicle has been detected
in the adjacent lane. The following vehicles can
have an influence on brake application: oncom-
ing traffic, vehicles that are overtaking and vehi-
cles that are driving parallel to your vehicle.
A further lane-correcting brake application can
only occur after your vehicle has returned to the original lane.
184Driving systems
Driving and parking
Display messagesPossible causes/consequences and0050Solutions
The yellow0024warning lamp lights up and th ered 0049 (USAonly)
or 0024 (Canada only) indicator lamp flashes .
It is no tpossibl eto apply th eelectric parking brak emanually.
XShift th etransmission to position P.
XVisitaqualified specialist workshop .
0027(USA
only)
004D( Canada
only)
Check Brake Fluid
Level
There is no tenough brak eflui din th ebrak efluid reservoir .
In addition ,th e0027 (USAonly) or 004D(Canada only) warning lamp
lights up in th einstrumen tcluste rand awarning tone sounds.
GWARNIN G
The braking effec tmay be impaired.
There is aris kof an accident.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XSecur eth evehicl eagainst rollin gaway (Ypage 137).
XConsult aqualified specialist workshop .
XDo notadd brak efluid .This does no tcorrec tth emalfunction .
0026
CheckBrakePadWear
The brak epads/linings hav ereached their wear limit.
US Aonly: th ered 0027 brakesystem warning lamp also lights up while
th eengin eis running.
XVisit aqualified specialist workshop .
0053
Inoperative
Oneor mor emain features of th embrace system are malfunctioning .
XVisitaqualified specialist workshop .
Collision Preven‐tionAssist Plu sCurrently Unavaila‐ble See Operator' sManual
COLLISION PREVENTION ASSIST PLU Sis temporarily no toperational.
Possibl ecauses are:
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation
Rth esystem is outside th eoperating temperature range
Rth eon-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
COLLISION PREVENTION ASSIST PLU Sis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 137).
XRestart th eengine.
Display messages20 9
On-board computer and displays
Z
Display messagesPossible causes/consequences and0050Solutions
Collision Preven‐tionAssist Plu sInoperative
COLLISION PREVENTION ASSIST PLU Sis temporarily inoperative due
to amalfunction .Adaptive Brake Assis tmay also hav efailed.
XVisit aqualified specialist workshop immediately.
PRE-SAFE Inopera‐tiv eSeeOperator' sManual
Importantfunction sof PRE-SAF E®havefailed. Al lother occupant
safet ysystems ,e.g. air bags ,remain available.
XVisit aqualified specialist workshop immediately.
PRE-SAFE FunctionsCurrently Limite dSee Operator'sMan ‐ual
PRE ‑S AF E®PLU Sor PRE‑SAFE®Brake is temporarily inoperative.
Possibl ecauses are:
Rfunction is impaire ddue to heav yrain or snow
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation
Rth esystem is outside th eoperating temperature range
Rth eon-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
PRE ‑S AF E
®PLU Sand PRE ‑S AF E®Brake are operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 137).
XRestart th eengine.
PRE-SAFE FunctionsLimite dSee Opera‐tor's Manual
PRE ‑S AF E®PLU Sor PRE‑SAFE®Brake is unavailable due to amal-
function .BA SPLU Swit hCross-Traffic Assis tmay also hav efailed.
XVisit aqualified specialist workshop immediately.
210Display messages
On-board computer and displays