
Problems with PARKTRONIC
ProblemPossible causes/consequences andMSolutions
Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is then
deactivated and the
indicator lamp on the
PARKTRONIC button
lights up.PARKTRONIC has malfunctioned and has switched off.
XIf problems persist, have PARKTRONIC checked at a qualified
specialist workshop.
Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is then
deactivated.The PARKTRONIC sensors are dirty or there is interference.
XClean the PARKTRONIC sensors (Ypage 335).
XSwitch 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
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 intervention and brake application
can assist you during parking and when exit-
ing a parking space. You may also use
PARKTRONIC (
Ypage 199).
Important safety notes
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.
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 may possibly indicate
parking spaces which are not suitable for
parking, for example:
Rwhere parking or stopping is prohibited
Rin front of driveways or entrances and exits
Ron unsuitable surfaces
202Driving systems
Driving and parking 

Problems with Night View Assist Plus
ProblemPossible causes/consequences andMSolutions
The picture quality of
Night View Assist Plus
has deteriorated.The windshield is fogged up on the inside.
XFold down camera cover (Ypage 337).
XDefrost the windshield (Ypage 141).
The windshield is iced up.
XDe-ice the windshield (Ypage 141).
The windshield wipers are smearing the windshield.
XReplace the wiper blades (Ypage 131).
The windshield is smeared after the vehicle has been cleaned in a
car wash.
XClean the windshield (Ypage 335).
There is windshield chip damage in the camera's field of vision.
XReplace the windshield.
The pedestrian and ani-
mal recognition is not
available.The infrared camera in the radiator grill is dirty.
XUse a soft cloth and water to clean the infrared camera.
Driving Assistance PLUS package
General notes
The Driving Assistance PLUS package con-
sists of DISTRONIC PLUS (
Ypage 182), Active
Blind Spot Assist (
Ypage 222) and Active
Lane Keeping Assist (
Ypage 225).
Active Blind Spot Assist
General notes
Active Blind Spot Assist uses a radar sensor
system, pointed toward the rear of the vehi-
cle, to monitor the area to the sides of the
vehicle which the driver is unable to see. A
warning display in the exterior mirrors draws
your attention to vehicles detected in the
monitored area. If you then switch on the cor-
responding turn signal to change lanes, you
will also receive a visual and audible collision
warning. If a risk of lateral collision is detec- ted, corrective braking may help you avoid a
collision. Before a course-correcting brake
application, Active Blind Spot Assist evalu-
ates the space in the direction of travel and at
the sides of the vehicle. For this, Active Blind
Spot Assist uses radar sensors which are
pointed in the direction of travel.
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
222Driving systems
Driving and parking 

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
automotive radar system only. Removal,
tampering, or altering of the device will void
any warranties, 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 se nso
rs
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, e.g. by
bicycle racks or overhanging loads. 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 oth-
erwise 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.
Active Blind Spot Assist monitors the area up
to 10 ft (3.0 m) behind your vehicle and
directly next to your vehicle, as shown in the
diagram.
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
Vehicles in the monitoring range are then not
indicated.
Active Blind Spot Assist may not detect nar-
row vehicles, such as motorcycles or bicy-
cles, or may only detect them too late.
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 at the inner edge of your lane.
Driving systems223
Driving an d parking
Z 

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 is a 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 in a non-critical driv-
ing situation.
The system may be impaired or may not func-
tion if:
Rthere is poor visibility, e.g. due to insuffi-
cient illumination of the road, or due to
snow, rain, fog or spray
Rthere is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
Rthe windshield is dirty, fogged up, damaged or covered, for instance by a sticker, in the
vicinity of the camera
Rthe radar sensors in the front or rear bump-
ers or the radiator trim are dirty, e.g.
obscured by snow
Rthere are no, several or unclear lane mark- ings for a lane, e.g. in areas with road con-
struction work
Rthe lane markings are worn away, dark or
covered up, e.g. by dirt or snow
Rthe distance to the vehicle in front is too
small and the lane markings thus cannot be
detected
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-correcting 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 steer-
ing wheel for up to 1.5 seconds.
In order that you are warned only when nec-
essary and in good time if you cross the lane
marking, the system recognizes certain con-
ditions 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 high-
way.
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 circum-
stances 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
226Driving systems
Driving and parking