
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.
You must select a lower gear in good time onlong and steep downhill gradients, especially ifthe vehicle is laden. By doing so, you will makeuse of the braking effect of the engine. Thisrelieves the load on the brake system and pre-vents the brakes from overheating and wear-ing 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 DISTRONICwhile driving on 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 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.
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
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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.
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HOLD function
General notes
The HOLD function can assist the driver in thefollowing situations:
RWhen pulling away, especially on steepslopes
RWhen maneuvering on steep slopes
RWhen waiting in traffic
The vehicle is kept stationary without thedriver having to depress the brake pedal.
The braking effect is canceled and the HOLDfunction deactivated when you depress theaccelerator pedal to pull away.
Important safety notes
GWARNING
If the vehicle is only braked using the HOLD
function, the vehicle may roll away in the fol-
lowing situations when you leave the vehi-
cle:
Rif there is a malfunction in the system or
in the voltage supply
Rif the HOLD function is deactivated by
depressing the accelerator pedal or brake
pedal, e.g. by a vehicle occupant
There is a risk of an accident.
Always deactivate the HOLD function and
secure the vehicle against rolling away
before you leave it.
!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
Deactivating the HOLD function (Ypage 165).
Activation conditions
You can activate the HOLD function if all of thefollowing conditions are fulfilled:
Rthe vehicle is stationary.
Rthe engine is running or if it has been auto-matically switched off by the ECO start/stop function.
Rthe driver's door is closed or your seat beltis fastened.
Rthe electric parking brake is released.
Rthe transmission is in position [, ^or \\.
RActive Distance Assist DISTRONIC is deacti-vated
Activating the HOLD function
XMake sure that the activation conditions aremet.
XDepress the brake pedal.
XQuickly depress the brake pedal furtheruntil Cappears in the multifunction dis-play.The HOLD function is activated. You canrelease the brake pedal.
iIf depressing the brake pedal the first timedoes not activate the HOLD function, waitbriefly and then try again.
Deactivating the HOLD function
The HOLD function is deactivated automati-cally if:
Ryou depress the accelerator and the trans-mission is in position [or ^.
Rthe transmission is in position ].
Ryou depress the brake pedal again with acertain amount of pressure untilHOLDHOLDdisap-pears from the multifunction display.
Ryou secure the vehicle using the electricparking brake.
Ryou activate Active Distance AssistDISTRONIC.
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