
Off-road fording
! Under no circumstances should you accel-
erate before entering the water. The bow
wave could cause water to enter and damage
the engine and other assemblies.
! Do not open any of the vehicle's doors while
fording. Otherwise, water could get into the
vehicle interior and damage the vehicle's
electronics and interior equipment. R
Establish how deep the water is and the char-
acteristics of the body of water before ford-
ing. R
Select the highest possible vehicle level. R
Shift to a lower gear using the left-hand steer-
ing wheel paddle shifter. R
Avoid high engine speeds. R
Enter and exit the water at a flat place and at
a steady walking pace. R
Drive slowly and at an even speed through the
water. R
Ensure that a bow wave does not form as you
drive. R
Do not stop and do not switch off the engine.
Water offers a high degree of resistance, and
the ground is slippery and in some cases
unstable. Therefore, it is difficult and danger-
ous to pull away in the water. R
Clean any mud from the tire tread after ford-
ing. R
Apply the brakes to dry them after fording.
Always observe the fording depth values
( Y
page 382).
Winter driving
G WARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
G DANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases such as carbon monoxide (CO) may enter the
vehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a
window on the side of the vehicle that is not
facing into the wind.
Have your vehicle winter-proofed at a qualified
specialist workshop at the onset of winter.
Drive particularly carefully on slippery road sur-
faces. Avoid sudden acceleration, steering and
braking maneuvers. Do not use cruise control or
Distance Pilot DISTRONIC.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed: X
Shift the transmission to position N .
When driving in snow with or without snow
chains, select driving program Slippery
( Y
page 139).
i Vehicles with a diesel engine: do not
cover the radiator, e.g. with a protective
cover. The measuring function of the on-
board diagnosis system may otherwise pro-
vide inaccurate values. Some of these values
are required by law and must therefore always
be accurate.
The outside temperature indicator is not
designed to serve as an ice-warning device and
is therefore unsuitable for that purpose.
Changes in the outside temperature are dis-
played after a short delay.
Indicated temperatures just above the freezing
point do not guarantee that the road surface is
free of ice. The road may still be icy, especially in
wooded areas or on bridges. You should pay
special attention to road conditions when tem-
peratures are around the freezing point.
For more information on driving with snow
chains, see ( Y
page 343).
For more information on driving with summer
tires, see ( Y
page 343).
Observe the notes in the "Changing a wheel"
section ( Y
page 361).Driving tips 161
Driving and parking Z

! A function or performance test should only
be carried out on a two-axle dynamometer.
Before you operate the vehicle on such a
dynamometer, please consult a qualified
workshop. You could otherwise damage the
drive train or the brake system.
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"
( Y
page 162).
DSR (Downhill Speed Regulation) General notes DSR is an aid to assist you when driving down-
hill. It keeps the speed of travel at the speed
selected 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 vehicle’s speed when it is acti-
vated and the transmission is in position D , R or
N . You can drive at a higher or a lower speed
than that set on the on-board computer at any
time by accelerating or braking.
Important safety notes
G WARNING
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.
If you fail to adapt your driving style, DSR can
neither reduce the risk of accident nor override
the laws of physics. DSR cannot take account of
road, weather and traffic conditions. DSR is only
an aid. You are responsible for the distance to
the vehicle in front, for vehicle speed, for brak-
ing in good time and for staying in your lane.
You are always responsible for keeping control
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, depend- ing on road surface and tire conditions. Select a
set speed suitable for the prevailing conditions
and when necessary, apply the brakes manually.
Activating DSR X
Press button C .
Indicator lamp D lights up.
The