2019 MERCEDES-BENZ SLC sensor

As a result, Active Distance Assist
DISTRONIC may neither give warnings nor
intervene in such situations. There is a risk
of an accident.
Always pay careful attention to the traffic
situation and be ready to brake.
GWARNING
Distance keeping assistant cannot always
clearly identify other road users and com-
plex traffic situations.
In such cases, distance keeping assistant
can:
Raccelerate or brake the vehicle unexpect-
edly
Rintervene unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, especially if distance keeping assis-
tant warns you.
GWARNING
Active Distance Assist DISTRONIC brakes
your vehicle with up to 50% of the maximum
possible deceleration. If this deceleration is
not sufficient, Active Distance Assist
DISTRONIC alerts you with a visual and
acoustic warning. There is a risk of an acci-
dent.
Adjust your speed in these cases and main-
tain sufficient distance.
Apply the brakes yourself and/or take eva-
sive action.
!When Active Distance Assist DISTRONICor the HOLD function is activated, the vehi-cle brakes automatically in certain situa-tions.
To avoid damage to the vehicle, deactivateActive Distance Assist DISTRONIC and theHOLD function in the following or similar sit-uations:
Rwhen towing the vehicle
Rin the car wash
Active Distance Assist DISTRONIC can neitherreduce the risk of an accident if you fail to
adapt your driving style, nor override the lawsof physics. Active Distance Assist DISTRONICcannot take into account road, weather or traf-fic conditions. Active Distance AssistDISTRONIC is only an aid. You are responsiblefor the distance to the vehicle in front, forvehicle speed, for braking in good time and forstaying in your lane.
Do not use Active Distance Assist DISTRONIC:
RIn road and traffic conditions which do notallow 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 losetraction and the vehicle could then skid
RIn poor visibility, e.g. due to fog, heavy rainor snow
Active Distance Assist DISTRONIC may notdetect narrow vehicles driving in front, e.g.motorcycles, or vehicles driving in a staggeredformation.
In particular, the detection of obstacles can beimpaired if:
RThere is dirt on the sensors or anything elsecovering 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 Active Distance Assist DISTRONIC no longerdetects a vehicle in front, Distance PilotDISTRONIC may unexpectedly accelerate tothe speed stored.
This speed may:
RBe too high if you are driving in a turninglane or an exit lane
RBe so high when driving in the right-handlane that you overtake vehicles in the left-hand lane
RBe so high in the left lane that you passvehicles driving on the right
If there is a change of drivers, advise the newdriver of the speed stored.
Driving systems145
Driving an d parking
Z

Selecting the Comfort or Economy
drive programs
In theComfortandEconomydrive programs,the driving characteristics of your vehicle aremore comfortable. Select one of these driveprograms if you favor a more comfortable driv-ing style. Also select these drive programswhen driving fast on straight roads, e.g. onstraight stretches of highway.
In urban traffic and stop-start traffic, drive pro-gramCis recommended.
XPress DYNAMIC SELECT buttonCrepeat-edly until theComfortorEconomydriveprogram is selected.
Selecting Sport mode
The firmer setting of the suspension tuning intheSportdrive program ensures even bettercontact with the road. Select this drive pro-gram when employing a sporty driving style,e.g. on winding country roads.
XPress DYNAMIC SELECT buttonCas manytimes as necessary until theSportdriveprogram is selected.
Selecting Sport Plus mode
The firmer suspension settings in theSportPlusdrive program ensure even better contactwith the road. Select this mode when employ-ing a sporty driving style, e.g. on winding coun-try roads or, ideally, when driving on closedrace circuits.
XPress DYNAMIC SELECT buttonCrepeat-edly until theSport Plusdrive program isselected.
Parking Assist PARKTRONIC
Important safety notes
Parking Assist PARKTRONIC is an electronicparking aid with ultrasound. It monitors thearea around your vehicle using six sensors inthe front bumper and four sensors in the rearbumper. Parking Assist PARKTRONIC visuallyand audibly indicates the distance betweenyour vehicle and an object.
Parking Assist PARKTRONIC is only an aid. It isnot a replacement for your attention to yourimmediate surroundings. You are alwaysresponsible for safe maneuvering, parking andexiting a parking space. Make sure that thereare no persons, animals or objects in themaneuvering area when you are maneuveringor parking.
!When parking, pay particular attention toobjects above or below the sensors, such asflower pots or trailer drawbars.PARKTRONIC does not detect such objectswhen they are in the immediate vicinity ofthe vehicle. You could damage the vehicleor the objects.
The sensors may not detect snow and otherobjects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic carwash, the compressed-air brakes on a truckor a pneumatic drill could causePARKTRONIC to malfunction.
PARKTRONIC may not function correctly onuneven terrain.
Parking Assist PARKTRONIC is activated auto-matically when you:
Rswitch on the ignition
Rshift the transmission to position[,^or\\
Rrelease the electric parking brake
Parking Assist PARKTRONIC is deactivated atspeeds above 11 mph (18 km/h). It is reacti-vated at lower speeds.
Driving systems153
Driving and parking
Z

Range of the sensors
General notes
Parking Assist PARKTRONIC does not take intoaccount obstacles located:
Rbelow the detection range, such as persons,animals or objects
Rabove the detection range, e.g. overhangingloads, tail sections or loading ramps oftrucks
CSensors in the front bumper, left-hand side(example)
The sensors must be free from dirt, ice orslush. They can otherwise not function cor-rectly. Clean the sensors regularly, taking carenot to scratch or damage them (Ypage 250).
Range
Front sensors
CenterApprox. 40 in (approx.100 cm)
CornersApprox. 24 in (approx.60 cm)
Rear sensors
CenterApprox. 48 in (approx.120 cm)
CornersApprox. 32 in (approx.80 cm)
Minimum distance
CenterApprox. 8 in (approx.20 cm)
CornersApprox. 6 in (approx.15 cm)
If there is an obstacle within this range, therelevant warning displays light up and a warn-ing tone sounds. If the distance falls below theminimum, the distance may no longer beshown.
154Driving systems
Driving and parking

Problems with Parking Assist PARKTRONIC
ProblemPossible causes/consequences andPPSolutions
Only the red segmentsin the Parking AssistPARKTRONIC warningdisplays are lit. You alsohear a warning tone forapproximately two sec-onds.
Parking AssistPARKTRONIC is deacti-vated after approx-imately 20 seconds andthe indicator lamp inthe Parking AssistPARKTRONIC buttonlights up.
Parking Assist PARKTRONIC has malfunctioned and has been deac-tivated.
XIf problems persist, have Parking Assist PARKTRONIC checked ata qualified specialist workshop.
Only the red segmentsin the Parking AssistPARKTRONIC warningdisplays are lit. ParkingAssist PARKTRONIC isdeactivated afterapproximately five sec-onds.
The Parking Assist PARKTRONIC sensors are dirty or there is inter-ference.
XClean the Parking Assist PARKTRONIC sensors (Ypage 250).
XSwitch the ignition back on.
The problem may be caused by an external source of radio or ultra-sound waves.
XCheck to see if Parking Assist PARKTRONIC works at a differentlocation.
Parking Guidance
Important safety notes
Parking Guidance is an electronic parking aidwith ultrasound. Ultrasound is used to meas-ure the road on both sides of the vehicle. Asuitable parking space is indicated by theparking symbol. You receive steering instruc-tions when parking. You can also still useParking Assist PARKTRONIC (Ypage 153).
Parking Guidance is only an aid. It is not areplacement for your attention to your immedi-ate surroundings. You are always responsiblefor safe maneuvering, parking and exiting aparking space. Make sure that there are nopersons, animals or objects in the maneuver-ing area when you are maneuvering or parking.
GWARNING
If objects are located above the detection
range, Parking Guidance may provide steer-
ing instructions too soon. You may cause a
collision as a result. There is a risk of an
accident.
If objects are located above the detection
range, stop and switch off Parking Assist.
!If they cannot be avoided, drive overobstacles such as curbs slowly and at anobtuse angle. Otherwise, you may damagethe wheels or tires.
When Parking Assist PARKTRONIC is switchedoff, Parking Guidance is also unavailable.
Parking Guidance may also display spaces notsuitable for parking, e.g.:
Rwhere parking or stopping is prohibited
Rin front of driveways or entrances and exits
Ron unsuitable surfaces
156Driving systems
Driving and parking

Important safety notes
GWARNING
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 vehi-
cle
As a result, Blind Spot Assist may not give
warnings in such situations. There is a risk
of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
Blind Spot Assist is only an aid. It may fail todetect some vehicles and is no substitute forattentive driving. Always ensure that there issufficient distance to the side for other roadusers and obstacles.
iUSA only:
This device has been approved by the FCCas a "Vehicular Radar System". The radarsensor is intended for use in an automotiveradar system only. Removing, tamperingwith, or altering the device will void any war-ranties, and is not permitted by the FCC. Donot tamper with, alter, or use in any non-approved way.
Any unauthorized modification to this devicecould void the user’s authority to operatethe equipment.
Radar sensors
The radar sensors for Blind Spot Assist areintegrated into the rear bumper. Make surethat the bumpers are free from dirt, ice orslush. The sensors must not be covered, forexample by cycle racks or overhanging loads.Following a severe impact or in the event ofdamage to the bumpers, have the function ofthe radar sensors checked at a qualified spe-cialist workshop. Blind Spot Assist may no lon-ger work properly.
Monitoring range of the sensors
In particular, the detection of obstacles can beimpaired if:
Rthere is dirt on the sensors or anything elsecovering the sensors
Rthere is poor visibility, e.g. due to fog, heavyrain, snow or spray
Rthere are narrow vehicles, e.g. motorcyclesor bicycles
Rthe road has very wide lanes
Rthe road has narrow lanes
Ryou are not driving in the middle of the lane
Rthere are barriers or other road boundaries
Vehicles in the monitoring range are then notindicated.
Blind Spot Assist monitors the area up to 10 ft(3.0 m) behind your vehicle and directly nextto your vehicle, as shown in the diagram. Forthis purpose, Blind Spot Assist uses radar sen-sors in the rear bumper.
If the lanes are narrow, vehicles driving in thelane beyond the lane next to your vehicle maybe indicated, especially if the vehicles are notdriving in the middle of their lane. This may bethe case if there are vehicles driving at theinner edge of their lanes.
Due to the nature of the system:
Rwarnings may be issued in error when driv-ing close to crash barriers or similar solidlane borders.
Rwarnings may be interrupted when drivingalongside long vehicles, e.g. trucks, for aprolonged time.
164Driving systems
Driving and pa rking

Important safety notes
GWARNING
If you operate information systems and com-
munication equipment integrated in the
vehicle when driving, you may be distracted
from the traffic situation. You could also
lose control of the vehicle. There is a risk of
an accident.
Only operate this equipment when the traffic
situation permits. If you are not sure that
this is possible, park the vehicle paying
attention to traffic conditions and operate
the equipment when the vehicle is station-
ary.
You must observe the legal requirements forthe country in which you are currently drivingwhen operating the on-board computer.
GWARNING
If the instrument cluster has failed or mal-
functioned, you may not recognize function
restrictions in systems relevant to safety.
The operating safety of your vehicle may be
impaired. There is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
The on-board computer only shows messagesor warnings from certain systems in the multi-function display. You should therefore makesure your vehicle is operating safely at alltimes.
If the operating safety of your vehicle isimpaired, pull over as soon as it is safe to doso. Contact a qualified specialist workshop.
For an overview, see the instrument panelillustration (Ypage 32).
Displays and operation
Instrument cluster lighting
The lighting in the instrument cluster, in thedisplays and the controls in the vehicle interiorcan be adjusted using the brightness controlknob.
The brightness control knob is located on thebottom left of the instrument cluster(Ypage 32).
XTurn the brightness control knob clockwiseor counter-clockwise.If you turn the light switch (Ypage 97) totheX,`orXposition, the bright-ness will depend upon the brightness of theambient light.
The light sensor in the instrument clusterautomatically controls the brightness of themultifunction display. In daylight, the dis-plays in the instrument cluster are not illu-minated.
Speedometer with segments
The segments in the speedometer indicatewhich speed range is available.
RCruise control activated (Ypage 142):
The segments light up from the storedspeed to the maximum speed.
RActive Distance Assist DISTRONIC activated(Ypage 144):
One or two segments in the set speed rangelight up.
RActive Distance Assist DISTRONIC detects avehicle in front moving more slowly than thestored speed:
The segments between the speed of thevehicle in front and the stored speed lightup.
Tachometer
!Do not drive in the overrevving range, asthis could damage the engine.
The red band in the tachometer indicates theengine's overrevving range.
The fuel supply is interrupted to protect theengine when the red band is reached.
Outside temperature display
You should pay special attention to road con-ditions when temperatures are around freezingpoint.
Displays and operation167
On-board computer and displays
Z

Display messagesPossible causes/consequences andPPSolutions
The yellow$warning lamp lights up and the redI(USAonly) or$(Canada only) indicator lamp flashes.
It is not possible to apply the electric parking brake manually.
XShift the transmission to position].
XVisit a qualified specialist workshop.
'(USA only)
M(Canada only)
Check Brake FluidCheck Brake FluidLevelLevel
There is not enough brake fluid in the brake fluid reservoir.
In addition, the'(USA only) orM(Canada only) warninglamp lights up in the instrument cluster and a warning tone sounds.
GWARNING
The braking effect may be impaired.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, payingattention to road and traffic conditions. Do not continue drivingunder any circumstances.
XSecure the vehicle against rolling away (Ypage 134).
XConsult a qualified specialist workshop.
XDo not add brake fluid. This does not correct the malfunction.
&
Check Brake PadCheck Brake PadWearWear
The brake pads/linings have reached their wear limit.
XVisit a qualified specialist workshop.
PRE-SAFE Inopera‐PRE-SAFE Inopera‐tive See Opera‐tive See Opera‐tor's Manualtor's Manual
Important functions of PRE-SAFE®have failed. All other occupantsafety systems, e.g. air bags, remain available.
XVisit a qualified specialist workshop immediately.
Active BrakeActive BrakeAssist FunctionsAssist FunctionsCurrently LimitedCurrently LimitedSee Operator's Man‐See Operator's Man‐ualual
Active Brake Assist is temporarily inoperative.
Possible causes are:
Rthe radar sensor system is temporarily inoperative, e.g. due toelectromagnetic radiation emitted by nearby TV or radio stationsor other sources of electromagnetic radiation
Rthe system is outside the operating temperature range
Rthe on-board voltage is too low
When the causes stated above no longer apply, the display messagedisappears.
Active Brake Assist is operational again.
If the display message does not disappear:
XPull over and stop the vehicle safely as soon as possible, payingattention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 134).
XRestart the engine.
188Displaymessages
On-b oard computer and displays

Display messagesPossible causes/consequences andPPSolutions
Active BrakeActive BrakeAssist FunctionsAssist FunctionsLimited See Opera‐Limited See Opera‐tor's Manualtor's Manual
Active Brake Assist is unavailable due to a malfunction.
XVisit a qualified specialist workshop.
Radar SensorsRadar SensorsDirty See Opera‐Dirty See Opera‐tor's Manualtor's Manual
The radar sensor system is malfunctioning.
Possible causes are:
Rdirt on sensors
Rheavy rain or snow
Rwhen driving on inter-urban roads without traffic or infrastructure,e.g. in desert-like areas
At least one driving system or driving safety system is malfunction-ing or is temporarily unavailable:
RActive Brake Assist
RActive Distance Assist DISTRONIC
Once the cause of the problem is no longer present, the driving anddrive safety systems will be available again. The display messagedisappears.
If the display message does not disappear:
XPull over and stop the vehicle safely as soon as possible, payingattention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 134).
XSwitch off the engine.
XClean all sensors (Ypage 250).
XRestart the engine.The display message disappears.
u
SRS MalfunctionSRS MalfunctionService RequiredService Required
The restraint system is malfunctioning. Theuwarning lamp alsolights up in the instrument cluster.
GWARNING
The air bags or Emergency Tensioning Devices may either be trig-gered unintentionally or, in the event of an accident, may not betriggered.
There is an increased risk of injury.
XVisit a qualified specialist workshop immediately.
Further information about the restraint system (Ypage 39).
Displaymessages189
On-b oard computer and displays
Z