Off-road ABS An ABS system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated on: R
Vehicles without the Offroad Engineering
package ( Y
page 219)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 220)
At speeds below 20 mph (30 km/h), the front
wheels lock cyclically during braking. The dig-
ging-in effect achieved in the process reduces
the stopping distance on off-road terrain. This
limits steering capability.
BAS (Brake Assist System)
General information BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 66).
G WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking X
Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. Active Brake Assist
General information
i Observe the "Important safety notes" sec-
tion ( Y
page 66).
Active Brake Assist consists of a distance warn-
ing function with an autonomous braking func-
tion and situation-dependent braking assis-
tance
Active Brake Assist can help you to minimize the
risk of a collision with the vehicle traveling in
front or reduce the effects of such a collision.
If Active Brake Assist detects that there is a risk
of collision, you will be warned visually and
acoustically. If you do not react to the visual and
audible collision warning, autonomous braking
can be initiated in critical situations. If you apply
the brake yourself in a critical situation, Adap-
tive Brake Assist supports you with situation-
dependent braking assistance.
Active Brake Assist is only available in certain
countries.
Important safety notes In particular, the detection of obstacles can be
impaired if: R
there is dirt on the sensors or anything else
covering the sensors R
there is snow or heavy rain R
there is interference by other radar sources R
there are strong radar reflections, for exam-
ple in parking garages R
a narrow vehicle is traveling in front, e.g. a
motorbike R
a vehicle is traveling in front on a different line R
you are driving a new vehicle or servicing on
the Active Brake Assist system has just been
carried out
Observe the notes in the section on breaking-
in ( Y
page 139).
Following damage to the front end of the vehicle,
have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.Driving safety systems 67
Safety Z
As a result, Distance Pilot DISTRONIC may
neither give warnings nor intervene in such
situations. There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
G WARNING
Distance Pilot DISTRONIC cannot always
clearly identify other road users and complex
traffic situations.
In such cases, Distance Pilot DISTRONIC may: R
give an unnecessary warning and then
brake the vehicle R
neither give a warning nor intervene R
accelerate or brake unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, especially if Distance Pilot DISTRONIC
warns you.
G WARNING
Distance Pilot DISTRONIC brakes your vehicle
with up to 50% of the maximum possible
deceleration. If this deceleration is not suffi-
cient, Distance Pilot DISTRONIC alerts you
with a visual and acoustic warning. There is a
risk of an accident.
Apply the brakes yourself in these situations
and try to take evasive action.
! When Distance Pilot DISTRONIC or the
HOLD function is activated, the vehicle
brakes automatically in certain situations.
To avoid damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or similar situations: R
when towing the vehicle R
in the car wash
The Distance Pilot DISTRONIC R
can neither reduce the risk of accident nor
override the laws of physics if you fail to adapt
your driving style. R
cannot take into account road, weather or
traffic conditions. R
is only an aid. You are responsible for the dis-
tance to the vehicle in front, for vehicle speed, for braking in good time and for staying in your
lane.
Do not use Distance Pilot DISTRONIC: R
in road and traffic conditions which do not
allow you to maintain a constant speed, e.g. in
heavy traffic or on winding roads R
on slippery road surfaces. Braking or accel-
erati ng could cause the drive wheels to lose
tra ction and the vehicle could then skid R
in poor visibility, e.g. due to fog, heavy rain or
snow
Distance Pilot DISTRONIC may not detect nar-
row vehicles driving in front, e.g. motorcycles, or
vehicles driving on a different line.
In particular, the detection of obstacles can be
impaired if: R
there is dirt on the sensors or anything else
covering the sensors R
there is snow or heavy rain R
there is interference by other radar sources R
there are strong radar reflections, for exam-
ple, in parking garages
If Distance Pilot DISTRONIC no longer detects a
vehicle in front, it may unexpectedly accelerate
to the speed stored.
This speed may: R
be too high if you are driving in a turning lane
or an exit lane R
be so high when driving in the right-hand lane
that you overtake vehicles in the left-hand
lane R
be so high when driving in the left-hand lane
that you overtake vehicles in the right-hand
lane
If there is a change of drivers, advise the new
driver of the speed stored.Driving systems 177
Driving an d parking Z
Range of the sensors General notes Parking Assist PARKTRONIC does not take into
account obstacles located: R
below the detection range, such as persons,
animals or objects R
above the detection range, such as overhang-
ing loads, truck overhangs or loading ramps
C
Sensors in the front bumper, left-hand side
(example)
The sensors must be free from dirt, ice or slush.
They can otherwise not function correctly. Clean
the sensors regularly, taking care not to scratch
or damage them ( Y
page 334). Range
C
Approx. 24 in (approx. 60 cm) (corners) D
Approx. 32 in (approx. 80 cm) (corners)