2016 MERCEDES-BENZ C-Class SEDAN rain sensor

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 narrow
vehicles, such as motorcycles or bicycles, 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 driv- ing in the middle of their lane. This may be the
case if there are vehicles at the inner edge of
your lane.
Due to the nature of the system:
Rwarnings may be issued in error when driving
close to crash barriers or similar solid lane
borders.
Rwarnings may be interrupted when driving
alongside particularly long vehicles, e.g.
trucks, for a prolonged time.
Warning display
:Warning display
Active Blind Spot Assist is not operational at
speeds below approximately 20 mph (30 km/h).
Vehicles in the monitoring range are then not
indicated.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h) , warning lamp :on the correspond-
ing 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). If you select the reverse gear, Active Blind Spot
Assist is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
When Active Blind Spot Assist is activated, gray
radar waves propagating backwards appear
next to the vehicle in the assistance display in
the multifunction display. Above a speed of
20 mph (30 km/h), the color of the radar waves
in the assistance display changes to green
;.
Active Blind Spot Assist is then ready for use.
Visual and acoustic collision warning
If you switch on the turn signals to change lanes and a vehicle is detected in the side monitoring
range, you receive a visual and acoustic collision warning. You will then hear a double warning
tone and red warning lamp :flashes. If the turn
signal remains on, detected vehicles are indica-
ted by the flashing of red warning lamp :.
There are no further warning tones.
Course-correcting brake application
If Active Blind Spot Assist detects a risk of a lat-
eral collision in the monitoring range, a course-
correcting brake application is carried out. This
is meant to assist you in avoiding a collision.
GWARNING
A course-correcting brake application cannot always prevent a collision. There is a risk of an
accident.
Always steer, brake or accelerate yourself,
especially if Active Blind Spot Assist warns
you or makes a course-correcting brake appli-
cation. Always maintain a safe distance at the
sides.
Driving systems221
Driving and parking
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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 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 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 vicin-
ity of the camera
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
broke
n 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 seconds.
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.
If a lane-correcting brake application occurs,
display :appears in the multifunction display.
The brake application also slightly reduces vehi-
cle speed.
This function is available in the range between
40 mph and 120 mph (60 km/h and 200 km/h).
A lane-correcting brake application can be made after driving over a lane marking detected 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 recog-
nized.
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. Oncoming vehicles, over-
taking vehicles and vehicles in adjacent lanes
can be detected.
iA further lane-correcting brake application
can only occur after your vehicle has returned
to the original lane.
No lane-correcting brake application occurs if:
Ryou clearly and actively steer, brake or accel- erate.
Ryou cut the corner on a sharp bend.
Ryou have switched on the turn signal.
Ra driving safety system intervenes, e.g. ESP®,
PRE-SAFE®Brake or Active Blind Spot Assist.
Driving systems223
Driving and parking
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Display messagesPossible causes/consequences andMSolutions
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 .
RMercedes-AMG vehicles: ES P®is deactivated
Rthesystem 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 177).
XRestart th eengine.
XMercedes-AMG vehicles: switch ES P®on again(Ypage 74).
PRE-SAFE FunctionsLimitedSee 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.
262Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
RadarSensorsDirtySee Operator' sMan ‐ual
At least on eof th efollowin gdrivin gsystems or drivin gsafet ysystems
is temporarily restricted or inoperative:
RPRE-SAF E®PLUS
RPRE-SAF E®Brake
RCOLLISION PREVENTION ASSIST PLU S
RActive LaneKeepin gAssis t
RActive Blind Spot Assis t
RDISTRONICPLU Swit hSteering Assis tand Stop&Go Pilo t
If th eradar sensor system in fron tis dirty, Active Blind Spot Assis twill
no tperfor m acourse-correcting brak eapplication .
Possibl ecauses are:
Rth esensor sin th eradiato rtrim and/o rin th ebumpers are dirty
Rth efunction of th edrivin gsystem or drivin gsafet ysystem is
impaire ddue to heav yrain or snow
A warning tone also sounds.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears. Al ldrivin gsystems or drivin gsafet ysystems are operative
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 177).
XSwitchoff th eengine.
XClean th esensor sin th efollowin glocation s (Ypage 339):
Rin theradiato rtrim
Rin th efron tbumper
Rin th erear bumper, particularly in th emiddle of th erear bumper
XRestart th eengine.
The display message disappears.
6
SRSMalfunctionSer ‐viceRequired
The restrain tsystem is faulty. The 6warning lamp also lights up in
th einstrumen tcluster.
GWARNIN G
The air bags or Emergency Tensioning Devices may either be triggered
unintentionally or, in th eevent of an accident, may no tbe triggered .
There is an increased ris kof injury.
XVisit aqualified specialist workshop immediately.
Fo rfurther information about th erestrain tsystem, see (
Ypage 46).
Display messages263
On-board computer and displays
Z