wheel speed MERCEDES-BENZ R-Class 2012 W251 User Guide

Driving tips
Kickdown
Use kickdown for maximum acceleration.
XVehicles for USA: fully depress the
accelerator pedal.
The transmission shifts to a lower gear
depending on the engine speed.XVehicles for Canada: depress the
accelerator pedal beyond the pressure
point.
The transmission shifts to a lower gear
depending on the engine speed.
Rocking the vehicle free
Rocking the vehicle free by shifting back and
forth between transmission positions D and
R can help to free a vehicle that has become
stuck in mud or snow. The engine
management system of the vehicle limits
shifting back and forth between transmission
positions D and R to a maximum speed of
5 mph (9 km/h). To shift back and forth
between transmission positions D and R,
move the selector lever up and down beyond
the pressure point.
Working on the vehicle
GWARNING
When working on the vehicle, engage the
parking brake and shift the automatic
transmission into park position P. Otherwise
the vehicle could roll away which could result
in an accident and/or serious personal injury.
Trailer towing
XWhen towing a trailer and driving downhill,
shift to the lower gear if the automatic
transmission constantly shifts between
two gears.XEngaging a lower gear and reducing the
speed reduces the risk of the engine
overheating.Program selector button
General information
The program selector button allows you to
choose between different driving
characteristics.
Program selector button
E EconomyComfortable, economical
drivingS SportSporty driving style
i
For further information on the automatic
drive program, see ( Y page 154).
XPress program selector button :
repeatedly until the letter for the desired
gearshift program appears in the
multifunction display.
Steering wheel paddle shifters
:Left-hand steering wheel paddle shifter;Right-hand steering wheel paddle shifterAutomatic transmission153Driving and parkingZ

You can restrict or derestrict the shift range
by using the steering wheel paddle shifters.
Automatic drive program
Drive program E is characterized by the
following:
R the vehicle pulling away more gently in
forward and reverse gears, unless the
accelerator pedal is depressed fully
R increased sensitivity. This improves driving
stability on slippery road surfaces, for
example
R the automatic transmission shifting up
sooner. This results in the vehicle being
driven at lower engine speeds and the
wheels being less likely to spin
Drive program S is characterized by the
following:
R sporty engine settings
R the vehicle pulling away in first gear
R the automatic transmission shifting up
later
R the fuel consumption possibly being higher
as a result of the later automatic
transmission shift points
Shift ranges
Introduction
When the automatic transmission is in
position D, it is possible to restrict or
derestrict the shift range ( Y page 154).
The shift range selected is shown in the
multifunction display. The automatic
transmission shifts only as far as the selected
gear.
Driving situations=You can use the engine's braking
effect.5To use the braking effect of the
engine on downhill gradients and
for driving:
R on steep mountain roads
R in mountainous terrain
R in arduous conditions4To use the braking effect of the
engine on extremely steep downhill
gradients and on long downhill
stretches
Restricting the shift range
XPull the left-hand steering wheel paddle
shifter.
The automatic transmission shifts down
one gear and restricts the shift range to the
relevant gear.
i If the engine exceeds the maximum
engine speed when shifting down, the
automatic transmission protects against
engine damage by not shifting down.
i If the maximum engine speed for the shift
range is reached and you continue to
accelerate, the automatic transmission
shifts up in order to prevent the engine
from overrevving, even if the shift range is
restricted.
Derestricting the shift range
XPull the right-hand steering wheel paddle
shifter.
The shift range is derestricted.
Clearing the shift range restriction
XPull and hold the right-hand steering wheel
paddle shifter until D is shown again in the
multifunction display.
The automatic transmission shifts from the
current shift range directly to D.154Automatic transmissionDriving and parking

XInsert DEF cap : as shown and turn it
clockwise as far as it will go.XStow lug wrench ; and ratchet wrench
= again.XFold the cargo compartment floor down.XClose the tailgate.XDrive at a speed above 10 mph (16 km/h).
The Check Additive See Operator's
Manual message goes out after
approximately one minute.
i If the Check Additive See
Operator's Manual message remains
shown in the multifunction display, add an
additional bottle of DEF.
i Then, have the DEF supply checked at a
qualified specialist workshop and
completely refilled if necessary.
Parking
Important safety notes
GWARNING
Do not park this vehicle in areas where
combustible materials can come into contact
with the hot exhaust system. Do not park the
vehicle on dry grassland or harvested grain
fields. Combustible materials, such as grass,
hay or leaves could be ignited by the hot
exhaust system and cause a vehicle fire.
Unintended vehicle movement can cause
serious personal injury or damage to the
vehicle or the vehicle drivetrain. To reduce
such risks, always do the following before
turning off the engine and leaving the vehicle:
R keep your right foot on the brake pedal.
R engage the parking brake.
R shift the automatic transmission to park
position P.
R slowly release the brake pedal.
R when parked on an incline, always turn the
front wheels towards the road curb.
R turn the SmartKey in the ignition lock to
position 0 and remove the SmartKey from
the ignition lock, or press the KEYLESS-GO
Start/Stop button.
R take the SmartKey with you and lock the
vehicle when leaving.
Switching off the engine
Important safety notes
GWARNING
Do not turn off the engine before the vehicle
has come to a complete stop. With the engine
not running, there is no power assistance for
the brake and steering systems. In this case,
it is important to keep in mind that a
considerably higher degree of effort is
necessary to brake and steer the vehicle.
GWARNING
Keep in mind that turning off the engine alone
only will shift the automatic transmission into
neutral position N automatically.
Always shift the automatic transmission into
park position P before turning off the engine.
Otherwise the vehicle could roll away which
could result in an accident and/or serious
personal injury.
i If you cannot turn off the engine as
described here, see "Engine emergency
stop" ( Y page 319).
Vehicles with automatic transmission
XApply the parking brake firmly.XShift the transmission to position P.
Using the SmartKey
XTurn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.
i If you turn off the engine with the
SmartKey and then remove it from the
ignition lock or open a front door, the
Parking163Driving and parkingZ

at high speeds. This improves the grip of the
brake pads.GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
You can find a description of Brake Assist
(BAS) on ( Y page 65).
Parking brake
If you drive on wet roads or dirt-covered
surfaces, road salt and/or dirt could get into
the parking brake.
In order to prevent corrosion and a reduction
in the braking power of the parking brake,
observe the following:
R Gently depress the parking brake from time
to time before beginning the journey.
R Drive a distance of approximately 110 yds
(100 m) with a maximum speed of 12 mph
(20 km/h).
GWARNING
While performing this procedure please
assure that the vehicle is stopped before
applying the parking brake. Otherwise the
rear wheels could lock up. You could lose
control of the vehicle and cause an accident.
In addition, the vehicle's brake lights do not
light up when the parking brake is engaged.
Make sure not to endanger any other road
users when you engage the parking brake.
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if:
R you drive at low speeds.
R the tires have adequate tread depth.
For this reason, in the event of heavy rain or
in conditions in which hydroplaning can occur
you must drive in the following manner:
R reduce your speed
R avoid ruts
R brake carefully
Driving on flooded roads
! Do not drive through flooded areas.
Check the depth of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic
components in the engine or the automatic
transmission. Water can also be drawn in
by the engine's air suction nozzles and this
can cause engine damage.
Do not allow water to enter the passenger
compartment or the engine compartment. If
you have to drive through a stretch of
standing water, please be aware the
following:
R the depth of the water must not exceed
10 inches (25 cm) for calm water
R you should drive no faster than at walking
pace.
i For vehicles with AIRMATIC package:
if you have set the raised level before
driving through a stretch of standing water,
the maximum water depth is 12 inches
(30 cm).
Winter driving
Important safety notes
GWARNING
If the vehicle becomes trapped in snow,
ensure that snow is kept away from the
exhaust pipe and from around the vehicle as
long as the engine is running. Otherwise,
poisonous carbon monoxide (CO) may enter
168Driving tipsDriving and parking

the vehicle, resulting in loss of consciousness
and even death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
At the onset of winter, have your vehicle
winterproofed at a qualified specialist
workshop, e.g. at an authorized Mercedes-
Benz Center.
i Vehicles with a diesel engine: do not
cover the radiator, e.g. with a protective
cover. The measuring function of the
Onboard Diagnosis System may otherwise
provide inaccurate values. Some of these
values are required by law and must
therefore always be accurate.
Winter tires
At temperatures below 45 ‡(+7 †), use
winter tires or all-season tires. Both types of
tire are identified by the M+S marking.
Only winter tires bearing the i snowflake
symbol in addition to the M+S marking
provide the best possible grip in wintry road
conditions. Only these tires will allow driving
safety systems such as ABS and ESP ®
to
function optimally in winter, as these tires
have been designed specifically for driving on
snow.
Use M+S tires of the same make and tread on
all wheels to maintain safe handling
characteristics.
GWARNING
M+S tires with a tread depth of less than 1
/ 6
inch (4 mm) must be replaced immediately.
They are no longer suitable for use in winter.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
Once you have mounted the winter tires:XCheck the tire pressures ( Y page 329).XRestart the tire pressure monitor
( Y page 331).GWARNING
If you use your spare wheel when M+S tires
are mounted on the other wheels, be aware
that the difference in tire characteristics
impairs cornering ability and reduces driving
stability. Adapt your driving style accordingly.
Have the spare wheel replaced by a normal
wheel with an M+S tire at the nearest
Mercedes-Benz Center.
Snow chains
For safety reasons, Mercedes-Benz
recommends that you only use snow chains
which have been specially approved for your
vehicle by Mercedes-Benz, or are of a
corresponding standard of quality.
! Vehicles with the Adaptive Damping
System (ADS): do not drive in ADS SPORT
mode if snow chains have been mounted.
The vehicle may otherwise be damaged.
! There is not enough space for snow
chains on some wheel sizes. Observe the
information under "Tires and wheels" in the
"Technical Data" section to avoid damage
to the vehicle or the wheels.
R Only use snow chains when driving on
roads completely covered by snow. Do not
exceed the maximum permissible speed of
30 mph (50 km/h). Remove the snow
chains as soon as possible when you are no
longer driving on snow-covered roads.
R Local regulations may restrict the use of
snow chains. Applicable regulations must
be observed if you wish to mount snow
chains.
R Snow chains must not be mounted on
emergency spare wheels.
Driving tips169Driving and parkingZ

If you intend to mount snow chains, please
bear the following points in mind:
R you may not attach snow chains to all
wheel-tire combinations; see the
information under "Wheel and tire
combinations" in the "Wheels and tires"
section.
R mount snow chains only in pairs and only
to the rear wheels. Observe the
manufacturer's installation instructions.
! If snow chains are mounted on the front
wheels, the snow chains could grind
against the bodywork or components of the
chassis. This could result in damage to the
vehicle or the tires.
! Vehicles with steel wheels: if you wish
to install snow chains to steel wheels, make
sure that you remove the respective
wheels' hubcaps first. The hubcaps may
otherwise be damaged.
i You may wish to deactivate
ESP ®
(Y page 66) when pulling away with
snow chains mounted. This way you can
allow the wheels to spin in a controlled
manner, achieving an increased driving
force (cutting action).
Slippery road surfacesGWARNING
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
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.
GWARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering
and braking maneuvers. Do not use cruise
control.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:XShift the transmission to position N.
i
For more information on driving with
snow chains, see ( Y page 169).
GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
Driving systems
Cruise control
Important safety notes
Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden or towing a trailer, you must
select shift range 1, 2 or 3 in good time. By
doing so, you will make use of the braking
effect of the engine, which relieves the load
on the brake system and prevents the brakes
from overheating and wearing too quickly.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can
set any road speed above 20 mph
(30 km/h).
GWARNING
The cruise control is a convenience system
designed to assist the driver during vehicle
operation. The driver is and must always
remain responsible for the vehicle's speed
and for safe brake operation.
Only use the cruise control if the road, traffic,
and weather conditions make it advisable to
travel at a constant speed.
170Driving systemsDriving and parking

RThe use of the cruise control can be
dangerous on winding roads or in heavy
traffic because conditions do not allow safe
driving at a constant speed.
R The use of the cruise control can be
dangerous on slippery roads. Rapid
changes in tire traction can result in wheel
spin and loss of control.
R Deactivate the cruise control when driving
in fog.
The "Resume" function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.GWARNING
When cruise control brakes, the brake pedal
is pulled back (i.e. operated automatically).
The area around the pedal must not be
blocked by obstacles:
R Do not place any objects in the footwell.
R Ensure that floormats and carpets are fixed
securely. In particular, do not place several
floormats on top of one another.
R Do not place your foot under the brake
pedal, as it could become trapped.
Non-compliance could lead you to cause an
accident in which you and/or others could be
seriously injured.
Cruise control lever:To store the current speed or a higher
speed;To store the current speed or a lower
speed=To deactivate cruise control?To store the current speed or to call up
the last stored speed
When you activate cruise control, the stored
speed is shown in the status indicator of the
multifunction display:
R Canada only: e.g. ¯90 Km/h
Storing and maintaining the current
speed
You can store the current speed if you are
driving faster than 20 mph (30 km/h).
XAccelerate the vehicle to the desired
speed.XBriefly press the cruise control lever
up : or down ; to the pressure point.XRemove your foot from the accelerator
pedal.
Cruise control is activated. The vehicle
automatically maintains the stored speed.
i Cruise control may be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient
evens out. Cruise control maintains the
stored speed on downhill gradients by
automatically applying the brakes.
Driving systems171Driving and parkingZ

conditions make it advisable to travel at a
constant speed.GWARNING
Use of the Distronic can be dangerous on
slippery roads. Rapid changes in tire traction
can result in wheel spin and loss of control.
The Distronic does not function in adverse
sight and distance conditions. Do not use the
Distronic during conditions of fog, heavy rain,
snow or sleet.
GWARNING
The Distronic cannot take weather conditions
into account. Switch off the Distronic or do
not switch it on if:
R roads are slippery or covered with snow or
ice. The wheels could lose traction while
braking or accelerating, and the vehicle
could skid.
R the Distronic system sensor cover is dirty
or visibility is diminished due to snow, rain
or fog, for example. The distance control
system functionality could be impaired.
Always pay attention to surrounding traffic
conditions even while the Distronic is
switched on. Otherwise, you may not be able
to recognize dangerous situations until it is
too late. This could cause an accident in which
you and/or others could be injured.
GWARNING
The "Resume" function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.
GWARNING
Close attention to road and traffic conditions
is imperative at all times, regardless of
whether or not the Distronic is activated.
Use of the Distronic can be dangerous on
winding roads or in heavy traffic because
conditions do not allow safe driving at a
constant speed.
The Distronic will not react to stationary
objects in the roadway (e.g. a stopped vehicle
in a traffic jam or a disabled vehicle). The
Distronic will also not respond to oncoming
vehicles.
Switch off the Distronic
R when changing from the left to the right
lane if vehicles are moving more slowly in
the left lane
R when entering a turn lane or highway off
ramp
R in complex driving situations, such as in
highway construction zones
In these situations, the Distronic will continue
to maintain the set speed unless deactivated.
The Distronic is designed and intended only
to maintain a set speed and keep a set
distance from moving objects in front of it.
i This device has been approved by the FCC
as a “Vehicular Radar System”. The radar
sensor is intended for use in an automotive
radar system only. Removal, tampering, or
altering of the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.174Driving systemsDriving and parking

Cruise control lever:To store the current speed or a higher
speed;To store the current speed or a lower
speed=To deactivate DISTRONIC?To store the current speed or to call up
the last stored speed
Switching on DISTRONIC, storing and
maintaining the current speed
GWARNING
The vehicle can be braked when DISTRONIC
is activated. For this reason, deactivate
DISTRONIC if the vehicle is to be set in motion
by other means (e.g. in a car wash or by
towing).
You can activate DISTRONIC in the following
circumstances:
R if the engine has been started and you have
been driving for up to two minutes
R while driving, except if you brake
R if the parking brake is not applied
R if ESP ®
is activated
R if the transmission is in position D
Activating while driving
When driving at speeds below 20 mph
(30 km/h) , you can only activate DISTRONIC
PLUS if the vehicle in front has been detected
and is shown in the multifunction display. If
the vehicle in front is not shown in the
multifunction display and is no longer being
detected, because it has changed lanes, for
example, DISTRONIC is deactivated and you
hear a warning tone.XBriefly pull the cruise control lever towards
you ? or press it up : or down ; to the
pressure point.
DISTRONIC is activated.XKeep the cruise control lever pressed
up : or down ; until the desired speed
is set.XRemove your foot from the accelerator
pedal.
Your vehicle adapts its speed to that of the
vehicle in front, but only up to the desired
stored speed.
i You can use the cruise control lever to set
the stored speed and the thumbwheel on
the cruise control lever to set the specified
minimum distance ( Y page 177).
i If you do not fully release the accelerator
pedal, the DISTRONIC Override message
appears in the multifunction display. The
set distance to a slower-moving vehicle in
front will then not be maintained. You will
be driving at the speed you determine by
the position of the accelerator pedal.
Driving
If there is no vehicle in front, DISTRONIC
operates in the same way as cruise control.
If a slower-moving vehicle is detected in front,
DISTRONIC causes your vehicle to brake and
maintain the preset distance to the vehicle in
front.
If DISTRONIC detects a faster-moving vehicle
in front, it increases the driving speed, but
only up to the desired speed you have stored.
GWARNING
If you depress the brake pedal, DISTRONIC is
deactivated. DISTRONIC will then no longer
brake your vehicle. In such cases, control the
distance from vehicles traveling in front with
the brake alone. You could otherwise cause
an accident and thereby injure yourself and
others. The driver remains fully responsible
Driving systems175Driving and parkingZ

for the vehicle's distance from other vehicles,
the speed being driven and for braking in good
time.
StoppingGWARNING
DISTRONIC must never be operated,
activated or deactivated by a passenger or
from outside the vehicle.
If DISTRONIC detects that the vehicle in front
is stopping, it brakes your vehicle until it is
stationary.
i Depending on the specified minimum
distance, your vehicle will come to a
standstill at a sufficient distance behind the
vehicle in front. The specified minimum
distance is set using the thumbwheel on
the cruise-control lever.
DISTRONIC is deactivated automatically
when stopping:
R on flat stretches of road or on downhill
gradients when the vehicle is stationary
R while the vehicle is still moving on uphill
gradients, to prevent the vehicle from
unexpectedly rolling back when
DISTRONIC is deactivated
If DISTRONIC is deactivated, you will hear a
warning tone.
XTo prevent the vehicle from rolling away,
apply the foot brake or parking brake.
Setting a speed
GWARNING
Keep in mind that it may take a brief moment
until the vehicle has made the necessary
adjustments.
Increase or decrease the set vehicle speed to
a value that the prevailing road conditions and
legal speed limits permit. Otherwise, sudden
and unexpected acceleration or deceleration
of the vehicle could cause an accident and/
or serious injury to you and others.
XPress the cruise control lever to the
pressure point, up : for a higher speed or
down ; for a lower speed.XKeep the cruise control lever pressed until
the desired speed is reached.XRelease the cruise control lever.
The new speed is stored. DISTRONIC is
activated and adjusts the vehicle's speed
to the new speed stored.
Making adjustments in 1 mph (Canada:
1 km/h) increments
XBriefly press the cruise control lever to the
pressure point, up : for a higher speed or
down ; for a lower speed.
The last speed stored is increased or
reduced.
Making adjustments in 5 mph (Canada:
10 km/h) increments
XBriefly press the cruise control lever
beyond the pressure point, up : for a
higher speed or down ; for a lower speed.
The last speed stored is increased or
reduced.
Storing the current speed or calling up
the last stored speed
GWARNING
The set speed stored in memory should only
be set again if prevailing road conditions and
legal speed limits permit. Possible
acceleration or deceleration differences
arising from returning to the preset speed
could cause an accident and/or serious injury
to you and others.
XBriefly pull the cruise control lever towards
you ?.XRemove your foot from the accelerator
pedal.
DISTRONIC is activated and accepts the
current speed if it is activated for the first176Driving systemsDriving and parking