page 100 MERCEDES-BENZ R-Class 2011 W251 Owner's Manual

The · distance warning lamp in the
instrument cluster will light up.
R you are approaching the vehicle in front
rapidly. An intermittent warning tone will
then sound and the · distance warning
lamp in the instrument cluster will light up.
You must apply the brakes yourself in order
to maintain the appropriate distance to the
vehicle in front and prevent a collision.GWarning!
If the distance warning lamp · in the
instrument cluster comes on while driving
and/or an intermittent warning sounds,
immediate attention on the part of the driver
is required. As required by the traffic
situation, apply the brakes and navigate
around a possible obstacle. However, do not
drive by relying on the distance warning
function, as this will result in an emergency
braking application. This will not always
enable you to avoid a collision, especially
when traveling on varying road surface
conditions and with varying driver reaction.
Complex driving situations are not always
fully recognized by the distance warning
function. This could result in wrong or missing
distance warnings.
XTo activate/deactivate: activate or
deactivate the distance warning function in
the on-board computer ( Y page 210).
After activation, the Ä symbol is
displayed in the lower multifunction
display.
Anti-theft systems
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
XTo activate with the SmartKey: remove
the SmartKey from the ignition lock.XTo activate with KEYLESS-GO: switch the
ignition off and open the driver's door.XTo deactivate: switch on the ignition.
i
The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be
started when the starter battery is fully
charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in
USA) or 1-800-387-0100 (in Canada).
ATA (Anti-Theft Alarm system)
A visual and audible alarm is triggered if the
alarm system is armed and you open:
R a door
R the vehicle with the mechanical key
R the tailgate
R the hood
The alarm is not switched off, even if you
close the open door that has triggered it, for
example.
i If the alarm stays on for more than 30
seconds, the emergency call system
mbrace (USA only) or Tele Aid (Canada
only) initiates a call to the Customer
Assistance Center automatically. The
emergency call system initiates the call
provided that:
R you have subscribed to the mbrace/Tele
Aid service
R the mbrace/Tele Aid service has been
activated properly
R the mobile phone, power supply and GPS
necessary are available
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Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
Correct driver's seat position
Observe the important safety notes on
( Y page 99).
XCheck whether you have adjusted seat =
properly.
Electrical seat adjustment ( Y page 100)
When adjusting the seat, make sure:
R you are as far away from the driver's air
bag as possible.
R you are sitting in a normal upright
position.
R you can fasten the seat belt properly.
R you have moved the backrest to an
almost vertical position.R you have set the seat cushion angle so
that your thighs are gently supported.
R you can depress the pedals properly.XCheck whether the head restraint is
adjusted properly ( Y page 101).
When doing so, make sure that you have
adjusted the head restraint so that the back
of your head is supported at eye level by
the center of the head restraint.
Observe the important safety notes on
( Y page 109).
XCheck whether steering wheel : is
adjusted properly.
Adjusting the steering wheel
manually( Y page 109)
Adjusting the steering wheel electrically
( Y page 110)
When adjusting the steering wheel, make
sure:
R you can hold the steering wheel with your
arms slightly bent.
R you can move your legs freely.
R you can see all the displays in the
instrument cluster clearly.
Observe the important safety notes on
( Y page 54).
XCheck whether you have fastened seat
belt ; properly ( Y page 55).
The seat belt should:
R fit snugly across your body
R be routed across the middle of your
shoulder
R be routed in your pelvic area across the
hip jointsXBefore starting off, adjust the rear-view
mirror and the exterior mirrors
( Y page 112) in such a way that you have
a good view of road and traffic conditions.XVehicles with memory function: save the
seat, steering wheel and exterior mirror
settings ( Y page 114).98Correct driver's seat positionSeats, steering wheel and mirrors
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Do not drive the vehicle without the seat head
restraints. Head restraints are intended to
help reduce injuries during an accident.
! To avoid damage to the seats and the seat
heating, observe the following information:
R do not spill any liquids on the seats. If
liquid is spilled on the seats, dry them as
soon as possible.
R if the seat covers are damp or wet, do not
switch on the seat heating. The seat
heating should also not to be used to dry
the seats.
R clean the seat covers as recommended;
see the " Interior care" section.
R do not transport heavy loads on the
seats. Do not place sharp objects on the
seat cushions, e.g. knives, nails or tools.
The seats should only be occupied by
passengers, if possible.
R when the seat heating is in operation, do
not cover the seats with insulating
materials, e.g. covers, bags, seat covers,
child seats or booster seats.
! When you move the seats, make sure that
there are no objects in the footwell or
behind the seats. Otherwise, you could
damage the seats and the objects.
! When the outer seats in the second row
are folded down, the front seats must not
be in their rearmost position. The front
seats and the outer seats in the second row
could otherwise be damaged.
! Make sure that the sun visor is folded up
before adjusting the backrest and head
restraint height. The head restraint and sun
visor could otherwise collide when the head
restraint is fully extended.
i The rear-compartment head restraints
can be removed ( Y page 102).
Please contact an authorized Mercedes-
Benz Center for more information.i Related topics:
R Cargo compartment enlargement
(folding the second and third rows of
seats forwards) ( Y page 250)
Adjusting the seats
i Vehicles without the memory function:
the seats can be adjusted within five
minutes of opening a front door.
The time span starts over if, within these
five minutes, you:
R open or close a front door
R insert the key into or remove the key
from the ignition lock
R switch the ignition on or off.
If the key is in position 2 in the ignition, you
can adjust the seats at any time.
:Head restraint height 8;Backrest angle=Seat fore-and-aft adjustment?Seat cushion angleASeat height
i
Vehicles with the memory function: if
PRE-SAFE ®
is triggered, the front-
passenger seat will be moved to a better
position if it was previously in an
unfavorable position.
i You can store the seat settings using the
memory function ( Y page 114).
8
Only for vehicles with the memory function.100SeatsSeats, steering wheel and mirrors
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Adjusting the head restraints
Adjusting the head restraints manually
Adjusting the head restraint height 9
! The head restraints may only be removed
in a qualified specialist workshop.
Mercedes-Benz recommends that you go
to an authorized Mercedes-Benz Center.
XIf the head restraint is fully lowered, it is
necessary to press release catch :.XTo raise: pull the head restraint up to the
desired position.XTo lower: press release catch : in the
direction of the arrow and push the head
restraint down to the desired position.
Adjusting the angle of the head restraints
GWarning!
Vehicles with Rear Seat Entertainment
System: When adjusting the head restraint,
make sure your fingers do not become caught
between the head restraint cushion and the
monitor. Failing to do so may lead to injury.
XPush or pull the lower edge of the head
restraint in the direction of the arrow.
Adjusting the head restraint height
electrically 10
XTo adjust the head restraint height:
slide
the switch for head restraint adjustment
( Y page 100) up or down in the direction of
the arrow.
Adjusting the luxury head restraints
GWarning!
When folding back the head restraint side
bolsters, do not put your hands between the
side bolster and the cushion holder. There is
a danger of becoming trapped.
XTo adjust the side bolsters of the head
restraint: push or pull right and/or left-9
For vehicles without memory function only.
10 Only on vehicles with memory function.Seats101Seats, steering wheel and mirrorsBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 101Z

Calling up a stored parking position
settingXWith the key in position 2 in the ignition
lock and the exterior mirror on the front-
passenger side activated, engage reverse
gear.
The exterior mirror on the front-passenger
side moves to the stored parking position.
The exterior mirror on the front-passenger
side moves back to its original position:
R as soon as you exceed a speed of 6 mph
(10 km/h)
R about ten seconds after you have
disengaged reverse gear
R if you press button = for the exterior
mirror on the driver's side
Memory functions
Storing settings
With the memory function, you can store up
to three different settings, e.g. for three
different people.
The following settings are stored as a single
memory preset:
R position of the seat, backrest and head
restraint
R driver's side: steering wheel position
R driver's side: position of the exterior
mirrors on the driver's and front-passenger
sides
GWarning!
The memory function can still be used when
the key has been removed. For this reason,
children should never be left unsupervised in
the vehicle. They could otherwise become
trapped when adjusting the seat or the
steering wheel.
GWarning!
Only use the memory function on the driver's
side when the vehicle is stationary. You could
otherwise be distracted from the traffic
conditions by the steering wheel and seat
moving of their own accord, and as a result
cause an accident.XAdjust the seat ( Y page 100).XOn the driver's side, adjust the steering
wheel (Y page 110) and the exterior mirrors
( Y page 112).XPress memory button M and one of the
storage position buttons 1, 2 or 3 within
three seconds.
The settings are stored in the selected
preset position. A tone sounds when the
settings have been completed.
Calling up a stored setting
XPress and hold the relevant storage
position button 1, 2 or 3, until the seat,
steering wheel and exterior mirrors are in
the stored position.
i The setting procedure is interrupted as
soon as you release the storage position
button.
114Memory functionsSeats, steering wheel and mirrors
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too low. Observe additional warning
messages in the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at an authorized Mercedes-Benz
Center.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. Contact an
authorized Mercedes-Benz Center.
Only install brake pads and use brake fluid
recommended by Mercedes-Benz.GWarning
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that safe
braking is substantially impaired. This could
result in an accident.
! A function or performance test may only
be carried out on a two-axle dynamometer.
If you are planning to have the vehicle
tested on such a dynamometer, contact an
authorized Mercedes-Benz Center to
obtain further information first. Otherwise,
the drive train or the brake system may
suffer damage.
! As the ESP ®
system operates
automatically, the engine and the ignition
must be switched off (SmartKey in position
0 or 1 in the ignition lock or Start/Stop
button in position 0 or 1) while the parking
brake is being tested on a brake
dynamometer (maximum 10 seconds).
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
If your brake system is only subjected to
moderate loads, you should regularly test
your brake system's function by forcefully
depressing the brake pedal when driving at
high speed. This also improves the brake
pads' friction.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 68).
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 approximately 110 yd (100 m)
without exceeding a 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
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Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Disabled
See Operator's
ManualThe front-passenger air bag is disabled during the journey even
though an adult or a person larger than a certain size is occupying
the front-passenger seat. If additional forces are applied to the
seat, the weight the system detects may be too low.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XHave the occupant get out of the vehicle.XSet the seat higher ( Y page 100).XMake sure that no objects are exerting force on the seat, e.g.
books, bags, etc. lying under, behind or beside the seat. These
forces may otherwise cause the system to detect too low a
weight and interpret the seat occupant's weight as less than it
actually is.XMake sure that the seat is unoccupied and has no objects placed
on it, close the front-passenger door, and switch on the ignition.
Observe the 42 (Y page 42) indicator lamps and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 42 indicator lamp must light up and remain lit.
When the indicator lamp is on, OCS ( Y page 42) has disabled
the front-passenger air bag.
R the display messages Front Passenger Airbag Enabled
See Operator's Manual or Front Passenger Airbag
Disabled See Operator's Manual cannot appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are met, the front-passenger seat can be
occupied again. Whether the 42 indicator lamp
remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are not met, the system is not operating correctly.
XVisit a qualified specialist workshop immediately.GWarning
If the 42 indicator lamp remains lit with an adult occupant on the front-passenger
seat even after performing the above corrective steps, do not have any passenger use the front-
passenger seat until the system has been repaired.
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Directives to be observed
R Only mount tires and wheels of the same
type and make.
R Only mount tires of the correct size onto
the wheels.
R After mounting new tires, run them in at
moderate speeds for the first 60 miles
(100 km) as they only reach their full
performance after this distance.
R Do not use tires until they are excessively
worn as the tire traction on wet road
surfaces decreases significantly when the
tread depth is less than 1
/ 8 in (3 mm).
R If the vehicle is heavily laden, check the tire
pressure and adjust it if necessary.
R When parking your vehicle, make sure that
the tires do not get deformed by the curb
or other obstacles. If it is necessary to drive
over curbs, speed humps or similar
elevations, try to do so slowly and at an
obtuse angle. Otherwise, the tires,
particularly the sidewalls, can get
damaged.
Maintenance and care of wheels and
tires
Checking wheels and tires
GWarning
Regularly check the tires for damage.
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle.
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
R Regularly check the wheels and tires of
your vehicle for damage (e.g. cuts,
punctures, tears, bulges on tires and
deformation or severe corrosion on
wheels), at least once a month, as well as
after driving off-road or on rough roads.
Damaged wheels can cause a loss of tire
pressure.
R Regularly check the tire tread depth and
the condition of the tread across the whole
width of the tire (Y page 321). If necessary,
turn the front wheels to full lock in order to
inspect the inner side of the tire surface.
R All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
install anything on the valve (such as tire
pressure monitoring systems) other than
the standard valve cap or other valve caps
approved by Mercedes-Benz for your
vehicle.
R Regularly check the pressure of all the tires
including the emergency spare wheel or the
spare wheel, particularly prior to long trips,
and correct the pressure as necessary
( Y page 322).
Service life of tires
The service life of tires depends on the
following factors amongst other things:
R driving style
R tire pressure
R mileage
Replace the tires after six years at the latest,
regardless of wear. This also applies to the
emergency spare wheel/spare wheel.
Tire tread
GWarning
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the tread wear indicators (TWI) become
visible at approximately 1
/ 16 in (1.6 mm), we
recommend that you do not allow your tires
to wear down to that level. As tread depth
approaches 1
/ 8 in (3 mm), the adhesion
properties on a wet road are sharply reduced.
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performance which all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
represent higher levels of performance on the
laboratory test wheel than the minimum
required by law.
Interchanging the wheels
GWarning
Rotate front and rear wheels only if the tires
are of the same dimension.
If your vehicle is equipped with mixed-size
tires (different tire dimensions front vs. rear),
tire rotation is not possible.
GWarning!
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
110 lb-ft (150 Nm).
Only use genuine Mercedes-Benz wheel bolts
specified for your vehicle’s rims.
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires
in the center.
If your vehicle's tire configuration allows, you
can rotate the wheels according to the
intervals in the tire manufacturer's warranty
book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3000 to 6000 miles
(5000 to 10000 km), or earlier if tire wear
requires. Do not change the direction of
wheel rotation.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is rotated. Check the tire pressures.
Information on changing a wheel and
mounting the spare wheel ( Y page 301).
Tire labeling
Overview of tire labeling
The following markings are on the tire in
addition to the tire name (sales designation)
and the manufacturer's name:
:Uniform Tire Quality Grading Standard
( Y page 340);DOT, Tire Identification Number
( Y page 339)=Maximum tire load ( Y page 334)?Maximum tire pressure ( Y page 330)AManufacturerBTire material ( Y page 340)CTire size designation, load-bearing
capacity and speed index ( Y page 337)DLoad index ( Y page 339)ETire name
i
Tire data is vehicle-specific and may
deviate from the data in the example.
336Tire labelingTires and wheels
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For further information on the load bearing
index, see load index ( Y page 339).
Speed index: speed index B specifies the
approved maximum speed of the tire.GWarning
Even when permitted by law, never operate a
vehicle at speeds greater than the maximum
speed rating of the tires.
Exceeding the maximum speed for which tires
are rated can lead to sudden tire failure,
causing loss of vehicle control and possibly
resulting in an accident and/or serious
personal injury and possible death, for you
and for others.
Regardless of the speed index always observe
the speed limits. Drive carefully and adapt
your driving style to the traffic conditions.
Summer tiresIndexSpeed ratingQup to 100 mph (160 km/h)Rup to 106 mph (170 km/h)Sup to 112 mph (180 km/h)Tup to 118 mph (190 km/h)Hup to 130 mph (210 km/h)Vup to 149 mph (240 km/h)Wup to 168 mph (270 km/h)Yup to 186 mph (300 km/h)ZR...Yup to 186 mph (300 km/h)ZR...(..Y)above 186 mph (300 km/h)ZRabove 149 mph (240 km/h)
R Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR"
in the size description depending on the
manufacturer (e.g. 245/40 ZR 18).
The service specifications consists of load
bearing index A and speed index B.
R If the size description of your tire includes
"ZR" and there are no service
specifications, ask the tire manufacturer in
order to find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed index in the service specification.
Example: 245/40 ZR18 97 Y. In this
example, "97Y" is the service specification.
The letter "Y" represents the speed index
and the maximum speed of the tire is
limited to 186 mph (300 km/h).
R Every tire that has a maximum speed above
186 mph (300 km/h) must have "ZR" in the
size description and the service
specification must be given in brackets.
Example: 275/40 ZR 18 (99 Y). The speed
index "(Y)" shows that the maximum speed
of the tire is above 186 mph (300 km/h).
Ask the tire manufacturer to find out the
maximum speed.All-weather tires and winter tiresIndexSpeed ratingQ M+S 43up to 100 mph (160 km/h)T M+S43up to 118 mph (190 km/h)H M+S 43up to 130 mph (210 km/h)V M+S43up to 149 mph (240 km/h)
i
Not all tires that have the M+S
identification offer the driving
characteristics of winter tires. Winter tires
have, in addition to the M+S identification,
the i snow flake symbol on the tire
sidewall. Tires with this identification fulfill
the requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC)
regarding the tire traction on snow and
43 or M+S i for winter tires.338Tire labelingTires and wheels
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