
G
Risk of accident
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 func-
tion if:
R several or no lane markings for a single lane
are present.
R there is poo rvisibility, e.g. due to insuffi-
cien tillumination 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 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.
Active Lane Keeping Assist cannot detect
road and traffic conditions. It is not a substi-
tute 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
weathe rconditions .Always pay attention to
traffic conditions and your surroundings. Oth-
erwise, you may fail to recognise dangers in
time, cause an accident and injure yourself
and others.
Warning vibration in the steering wheel
A warning can be given when 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. 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 switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Lane-correcting brake application
If you leave your lane under certain circum-
stances, the vehicle will brake briefly on one
side. This is designed to help you bring the
vehicle back into the original lane.
This function is available in the range between
60 km/h and 200 km/h.
A lane-correcting brake application can only
be made after driving over a solid, recognis-
able lane marking. Befor ethis, a warning
must be emitted by means of intermittent
vibration in the steering wheel. In addition, a
lane with lane markings on both sides must
be recognised. The brake application also
slightly reduces driving speed.
If a lane-correcting brake application occurs,
the following message appears in the multi-
function display: 190
Driving systemsDriving and parking

i
A further lane-correcting brake applica-
tion can only occur after your vehicle has
returned to the original lane. G
Ris
kofa ccident
Active Lane Keeping Assist does no tkeep
your vehicle in its lane. It is only an aid
designed to assist driving. It is not a substitute
for attentive driving. Corrective braking may
not always be sufficien tto return your vehicle
to its original lane. In such cases, you must
steer the vehicle yourself to ensure that it
does not leave the lane.
Active Lane Keeping Assist cannot detect the
current traffic situation or other road users.
Ensure at all times that there is sufficient lat-
eral distance between you and other road
users or obstacles. In rare cases, broken lines
or certain structures on the road surface may
be detected by the system as solid lane mark-
ings. You can, for example, countersteer gen-
tly at any time to cancel inappropriate braking
action, e.g. if you intentionally drive across a
solid lane marking.
Active Lane Keeping Assist cannot take
weather conditions into account.
You are responsible for the vehicle's speed,
correc tsteering and for braking in good time.
Always adap tyour 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 others.
No lane-correcting brake application occurs
if:
R you clearly and actively steer, brake, or
accelerate.
R you cut the corner on a sharp bend. R
you switch on the turn signals.
R a driving safety system intervenes, such as
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R you have adopted a sporty driving style with
high cornering speeds or high rates of
acceleration.
R ESP ®
is deactivated.
R the transmission is not in position D.
R a loss of tyre pressure or a defective tyre
has been detected and displayed.
Active Lane Keeping Assist does not detect
road and traffic conditions. An inappropriate
brake application may be interrupted at any
time if you:
R steer slightly in the opposite direction
R use a turn signal
R clearly brake or accelerate
Al ane-correcting brake applicatio nis inter-
rupted automatically if:
R a driving safety system intervenes, such as
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R lane markings can no longer be recognised.
Activating Active Lane Keeping Assist X
Activate Active Lane Keeping Assist using
the on-board computer (Y page 205).
Symbol :appears in the multifunction
display.
If you drive at speeds above 60 km/h and
lane markings are detected, symbol :is dis-
played in green. Active Lane Keeping Assist
is ready for use. Driving systems
191Driving and parking Z

X
Press a.
The curren tselection is displayed.
X To activate/deactivate: pressa
again.
Activating/deactivating Lane Keeping
Assist You can use the
Lane Keep. Asst. function
to activate/deactivate Lane Keeping Assist
(Y page 185) or Active Lane Keeping Assist
(Y page 189).
X Press =or; on the steering wheel
to select the Assist. menu.
X Press 9or: to select Lane Keep.
Asst. .
X Press a.
If the function is activated, the road mark-
ings are shown in red in the multifunction
display.
X To activate/deactivate: pressa
again.
When Lane Keeping Assist or Active Lane
keeping Assist is activated, the multifunction
display shows the Ãsymbol when the igni-
tion is switched on. Service menu
In the
Service menu you can:
R call up display messages ( Ypage 215)
R reset the tyre pressure loss warning system
(Y page 306) or check the tyre pressure
electronically (Y page 307)
R call up the service due date (Y page 270) Setup menu
Introduction In the
Settings menu, you have the following
options:
R changing the instrument cluster settings
R changing the time/date settings 30
R changing the light settings
R changing the vehicle settings
R changing the auxiliary heating settings
R changing the convenience settings
R restoring the factory settings
Instrument cluster Selecting the unit of measurement for dis-
tance
The
Display unit Speed-/odometer func-
tion allows you to choose whether certain
displays appear in kilometres or miles.
The selected unit of measuremen tfor dis-
tance applies to:
R the digital speedometer in the Trip menu
R the total distance recorder and the trip
meter
R the trip computer
R the current consumption and the range
R the navigation instruction in the Navi menu
R cruise control
R SPEEDTRONIC
R DISTRONIC PLUS
R ASSYST PLUS service interval display
30 This function is not available on vehicles with Audio 50 APS, Audio 55 APS or COMAND APS. Menus and submenus
205On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
Radar sensor
deactivated autom.
See Owner's Manual Vehicles with a navigation system: the vehicle is close to a radio
telescope facility and is therefore prohibited from transmitting any
rada
rsignals .The radar sensor system has switched off automat-
ically.
DISTRONIC PLUS (Y page 154) is switched off automatically if it
is activated. Awarning tone also sounds.
If Blind Spot Assist (Y page 183) or Active Blind Spot Assist
(Y page 186) are activated, they are switched off automatically.
The yellow 9indicator lamps also light up in the exterior mir-
rors.
BAS PLUS (Brake Assist PLUS) (Y page 57) and the
PRE-SAFE ®
Brake (Y page 61) are also no tavailable.
X Drive on.
These functions are available again as soon as the vehicle is far
enough away from the radio telescope facility (Y page 327).Lane Keeping
Assist currently
unavailable. see
Owner's Manual
or
Active Lane Keep‐
ing Assist cur‐
rently unavailable
see Owner's Manual Lane Keeping Assist or Active Lane Keeping Assist is deactivated
and temporarily inoperative if:
R
the windscreen is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the lane markings are worn, dark or covered, for example by dirt
or snow.
Lane Keeping Assist or Active Lane Keeping Assist is operational
again and the display message disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the camera is fully operational again.
If the display message continues to be displayed:
X Clean the windscreen. Lane Keeping
Assist inoperative
or
Active Lane Keep‐
ing Assist inoper‐
ative Lane Keeping Assist or Active Lane Keeping Assist is faulty.
X
Visi taqualified specialist workshop. 228
Display messagesOn-board computer and displays