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Storing or calling up a speed
GWARNING
If you call up the stored speed and it differs
from the current speed, the vehicle acceler-
ates or decelerates. If you do not know the
stored speed, the vehicle could accelerate
or brake unexpectedly. There is a risk of an
accident.
Pay attention to the road and traffic condi-
tions before calling up the stored speed. If
you do not know the stored speed, store the
desired speed again.
XBriefly pull the cruise control lever towardsyou
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Active Distance Assist DISTRONIC
General notes
Active Distance Assist DISTRONIC regulatesthe speed and automatically helps you main-tain the distance from the vehicle detected infront. Vehicles are detected with the aid of theradar sensor system. Active Distance AssistDISTRONIC brakes automatically to avoidexceeding the set speed or to maintain thedesignated distance from the vehicle in front.
Change into a lower gear in good time on longand steep downhill gradients. This is especiallyimportant if the vehicle is laden. By doing so,you will make use of the braking effect of theengine. This relieves the load on the brake sys-tem and prevents the brakes from overheatingand wearing too quickly.
If Active Distance Assist DISTRONIC detectsthat there is a risk of a collision with the vehi-cle in front, you will be warned visually andaudibly. Active Distance Assist DISTRONICcannot prevent a collision without your inter-vention. An intermittent warning tone will thensound and the distance warning lamp will lightup in the instrument cluster. Brake immedi-ately in order to increase the distance fromthe vehicle in front, or take evasive action, pro-vided it is safe to do so.
For Active Distance Assist DISTRONIC toassist you when driving, the radar sensor sys-tem must be operational.
Active Distance Assist DISTRONIC operates inthe speed range between 0 mph (0 km/h) and120 mph (200 km/h).
Do not use Active Distance Assist DISTRONICon roads with steep gradients.
As Active Distance Assist DISTRONIC trans-mits radar waves, it can resemble the radardetectors of the responsible authorities. Youcan refer to the relevant chapter in the Opera-tor's Manual if questions are asked about this.
iUSA only: This device has been approvedby the FCC as a "Vehicular Radar System".The radar sensor is intended for use in anautomotive radar system only. Removal,tampering, or altering of the device will voidany warranties, and is not permitted by theFCC. Do not tamper with, alter, or use in anynon-approved way.
Any unauthorized modification to this devicecould void the user's authority to operatethe equipment.
iCanada only: This device complies withRSS-210 of Industry Canada. Operation issubject to the following two conditions:
1. This device may not cause interference,and
2. This device must accept any interferencereceived, including interference that maycause undesired operation of the device.
Removal, tampering, or altering of thedevice will void any warranties, and is notpermitted. Do not tamper with, alter, or usein any non-approved way.
Any unauthorized modification to this devicecould void the user's authority to operatethe equipment.
Important safety notes
GWARNING
Active Distance Assist DISTRONIC does not
react to:
Rpeople or animals
Rstationary objects in the road, e.g. stop-
ped or parked vehicles
Roncoming vehicles and crossing traffic
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
Active Distance Assist DISTRONIC does not
react to:
Rpeople or animals
Rstationary objects in the road, e.g. stop-
ped or parked vehicles (vehicles without
the Driving Assistance package)
Rstationary objects in the road, e.g. stop-
ped or parked vehicles, if sufficient detec-
tion is not possible (vehicles with the Driv-
ing Assistance package)
Roncoming vehicles and crossing traffic
144Driving systems
Driving and pa rking
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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
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