Hill start assist system, Downhill speed regulation (dsr), Controls in detail – Mercedes-Benz M-Class 2009 Owners Manual User Manual
Page 168
Driving systems
166
The hill start assist system is not designed
to function as a parking brake and does not
prevent the vehicle from moving when
parked on an incline.
Always engage the parking brake in
addition to shifting the automatic
transmission into park position
P.
On uphill grades with a gradient angle of more
than 5°, the hill start assist system maintains
the pressure in the brake system for
approximately 1 second after you have
released the brake pedal. Therefore, you can
start off smoothly without the vehicle moving
immediately after releasing the brake pedal.
X
Depress the brake pedal.
X
Shift the automatic transmission into drive
position
D or reverse gear R.
X
Release the brake pedal.
X
Carefully depress the accelerator pedal.
The hill start assist system is inactive
R
when starting off on a level road or downhill
grades
R
with the automatic transmission in neutral
position
N
R
with the parking brake engaged
R
if the ESP
®
has switched off due to a
malfunction
The Downhill Speed Regulation (DSR) is a
convenience system designed to assist the
driver during vehicle operation. The system
must be set to be appropriate for the
topographical and weather conditions
encountered which can change quickly.
The driver is and must remain at all times
responsible for the vehicle speed and for
safe brake operation.
Depending on the programmed speed,
actual vehicle speed and gradient,
switching on the DSR while driving can
cause the vehicle to slow down rapidly and
you may hear a sound which is caused by
the activation of the vehicle’s brake system
through the DSR. Sudden and unexpected
deceleration can result in loss of vehicle
control, causing an accident and/or
serious personal injury to you and others.
Do not switch on the DSR in a circumstance
where rapid deceleration could result in a
loss of vehicle control.
For more information, see “Off-road
driving” (
The DSR is an aid for driving downhill. The
DSR regulates your vehicle’s speed when
driving downhill to the value set in the control
system (
downhill gradient is, the greater the brake
application. On flat road surfaces, the DSR
brakes only slightly or not at all.
The DSR regulates the vehicle’s speed in
automatic transmission positions
D, or R.
i
In addition, make use of the engine’s
braking effect by shifting the automatic
transmission into a lower gear.
You can drive slower or faster than the set
speed at any time by braking the vehicle or
depressing the accelerator pedal.
i
Whenever the DSR is switched on, the
DSR will use the programmed default
speed to regulate the vehicle’s speed. The
Controls in detail