Mercedes-Benz 2015 M-Class Operator's Manual page 252

Driving systems
250
qualified workshop. You could otherwise
damage the drive train or the brake system.
4MATIC ensures that all four wheels are per-
manently driven. Together with ESP
4ETS, it improves the traction of your vehicle
whenever a drive wheel spins due to insuffi-
cient grip.
i
In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires (M+S tires), with snow
chains if necessary.
Further information about "Driving off-road"
( page 191).
Y
DSR (Downhill Speed Regulation)
Important safety notes
DSR assists you when driving downhill. It
keeps the speed of travel at the speed set on
the on-board computer. The steeper the
downhill gradient, the greater the DSR brak-
ing effect on the vehicle. When driving on flat
stretches of road or on an uphill gradient, the
DSR braking effect is minimal or nonexistent.
DSR controls the set speed when it is active
and the automatic transmission is in the D, R
or N position. By accelerating or braking, you
can always drive at a higher or a lower speed
than that set on the on-board computer.
Further information about "Driving off-road"
( page 191).
Y
If you fail to adapt your driving style, DSR can
neither reduce the risk of accident nor over-
ride the laws of physics. DSR cannot take
account of road, weather and traffic condi-
tions. DSR is only an aid. You are responsible
for the distance to the vehicle in front, for
vehicle speed, for braking in good time and for
staying in your lane.
You are always responsible for keeping con-
trol of the vehicle and for assessing whether
the downhill gradient can be managed. DSR
may not always be able to keep to the set
speed, depending on road surface and tire
conditions. Select a set speed suitable for the
prevailing conditions and when necessary,
apply the brakes manually.
G WARNING
®
and
If the speed driven and the set speed deviate
and you activate DSR on a slippery road sur-
face, the wheels may lose traction. There is an
increased danger of skidding and accidents.
Before switching DSR on, please take into
consideration the road surface and the differ-
ence between driving speed and the set
speed.
Activating DSR
G WARNING
If you drive faster than the set speed and acti-
vate DSR, the vehicle will decelerate on down-
hill gradients. If you do not know the set
speed, the vehicle could decelerate unexpect-
edly. There is a risk of an accident.
Decelerate the vehicle to the set speed before
activating DSR. If you do not know what the
stored set speed is, store the desired set
speed again.
Example: vehicles with the ON&OFFROAD package
DSR button
:
DSR indicator lamp
;
Press button :.
X
Indicator lamp ; lights up.
The à DSR symbol appears in the mul-
tifunction display.
You can only activate DSR when driving at
speeds below 25 mph (40 km/h).