2010 MERCEDES-BENZ R320 spare tire

The TPMS is equipped with a combination low
tire pressure/ TPMS malfunction telltale in
the
instrument cluster. Depending on how the
telltale illuminates, it indicates a low tire
pressure condition or a malfunction in the
TPMS system itself:
R If the telltale illuminates continuously, one
or more of your tires is significantly
underinflated. There is no malfunction in
the TPMS.
R If the telltale flashes for 60 seconds and
then stays illuminated, the TPMS system
itself is not operating properly.
The TPMS only functions on wheels that are
equipped with the proper electronic sensors. G
Warning!
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust

tire inflation pressure according to the
Tire and Loading Information placard or the
supplemental tire inflation pressure
information on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g. tire
blowout caused by a foreign object). In this
case bring the vehicle to a halt by carefully
applying the brakes and avoiding abrupt
steering maneuvers. G
Warning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the Tire and Loading
Information placard on the driver’s door B-
pillar

or the tire inflation pressure label on the
inside of the fuel filler flap. If your vehicle has
tires of a different size than the size indicated
on the Tire and Loading Information placard
or the tire inflation pressure label, you should
determine the proper tire inflation pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale

illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle’s
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire
maintenance, and it is the driver’s
responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately 1 minute and then
remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists. When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
i If a condition causing the TPMS to
malfunction develops, it may take up to
10 minutes for the system to signal a Tires and wheels
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malfunction using the TPMS telltale
flashing and illumination sequence.
The telltale extinguishes after a few
minutes driving if the malfunction has been
corrected.
Tire pressure inquiries are made using the
multifunction display. The current tire
inflation pressure for each tire appears in the
multifunction display after a few minutes of
driving.
i Possible differences between the
readings of a tire pressure gauge of an air
hose, e.g. gas station equipment, and the
vehicle’s control system can occur. The tire
pressure displayed by the control system
apply to sea level. In high-altitude
locations, the reading on a tire pressure
gauge will be higher than the reading issued
by the vehicle’s control system. Do not
reduce the tire inflation pressure under
such circumstances.
X Switch on the ignition.
X Press button V or U on the
multifunction steering wheel repeatedly
until the standard display appears in the
multifunction display ( Y page 126).
X Press button & or * until the current
inflation pressure for each tire appears in
the multifunction display. Example illustration
When the vehicle has been parked for longer
than 20 minutes, the message Tire
pressure displayed after driving
for a few minutes. appears in the
multifunction display.
The TPMS recognizes new wheels or sensors
automatically after the learn-in phase. As long as the tire inflation pressure values cannot be
allocated to the individual wheels, the
message
Tire Pressure Monitor Active
appears. Despite this message, the tire
inflation pressure values are monitored
already.
i With a spare wheel mounted, the system
may still indicate the tire inflation pressure
of the removed road wheel for some
minutes. If this happens, keep in mind that
the indicated value where the spare wheel
is mounted does not reflect the actual
spare tire inflation pressure.
i Operating radio transmission equipment
(e.g. wireless headsets, two-way radios) in
or near the vehicle could cause the TPMS
to malfunction.
i This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful interference, and
2. this device must accept any interference received, including
interference that may cause undesired.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Tire inflation pressure warnings
If the system detects a significant loss of tire
inflation pressure in one or more than one
tire, a message appears in the multifunction
display. In addition, an acoustic warning
sounds and the low tire pressure telltale in the
instrument cluster comes on. Example illustration234
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Weight Rating (GVWR) and the Gross Axle
Weight Rating (GAWR) for either the front or
rear axle. You can obtain the GVWR and
GAWR from the certification label. The
certification label can be found on the driver’s
door B-pillar, see the “Technical data” section
(Y page 344).
Gross Vehicle Weight Rating (GVWR): The
total weight of the vehicle, all occupants, all
cargo, and the trailer tongue load (if
applicable) must never exceed the GVWR.
Gross Axle Weight Rating (GAWR): The total
allowable weight that can be carried by a
single axle (front or rear).
To assure that your vehicle does not exceed
the maximum permissible weight limits
(GVWR and GAWR for front and rear axle),
have the loaded vehicle (including driver,
passengers and all cargo and, if applicable,
trailer fully loaded) weighed on a suitable
commercial scale.
Trailer tongue load
The tongue load of any trailer is an important
weight to measure because it affects the load
you can carry in your vehicle. If a trailer is
towed, the tongue load must be added to the
weight of all occupants riding and any cargo
you are carrying in the vehicle. The tongue
load typically is between 10% and 15% of the
trailer weight and everything loaded in it.
Maximum tire load
G
Warning!
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure. i
For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
The maximum tire load rating : is the
maximum weight the tires are designed to
support.
For more information on tire load rating, see
(Y page 245).
For information on calculating total and cargo
load capacities, see ( Y page 237). Direction of rotation
Unidirectional tires offer added advantages,
such as better hydroplaning performance. To
benefit, however, you must make sure the
tires rotate in the direction specified.
An arrow on the sidewall indicates the
intended direction of rotation of the tire.
Spare wheels may be mounted against the
direction of rotation (spinning) even with a
unidirectional tire for temporary use only until
the regular drive wheel has been repaired or
replaced. Always observe and follow
applicable temporary use restrictions and
speed limitations indicated on the spare
wheel. MOExtended system
The MOExtended system allows you to
continue driving your vehicle even if there is
a total loss of pressure in one or more tires. 240
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You may only use the MOExtended system in
conjunction with the tire pressure loss
warning system (
Y page 231) or the
Advanced TPMS (Y page 232).
i Vehicles with MOExtended system are
not factory-equipped with a TIREFIT kit.
When
retrofitting with tires that do not have
run-flat characteristics, e.g. winter tires,
you should also equip your vehicle with a
TIREFIT kit. TIREFIT kits are available at any
authorized Mercedes-Benz Center.
For information on driving in case of pressure
loss in one or more tires (emergency mode),
see the “Practical Hints” section
(Y page 330). Tire care and maintenance
G
Warning!
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.
Check the tire inflation pressure at least once
a month. For more information on checking
tire inflation pressure, see “Recommended
tire inflation pressure” ( Y page 228).
Tire inspection Every time you check the tire inflation
pressure, you should also inspect your tires
for the following:
R
excessive treadwear ( Y page 241)
R cord or fabric showing through the tire’s
rubber
R bumps,

bulges, cuts, cracks or splits in the
tread or side of the tire
Replace the tire if you find any of the above
conditions. Make sure you also inspect the spare tire
periodically

for condition and inflation. Spare
tires will age and become worn over time even
if never used, and thus should be inspected
and replaced when necessary.
Life of tire G
Warning!
Tires and spare tire should be replaced after
6 years, regardless of the remaining tread.
The service life of a tire is dependent upon
varying factors including but not limited to:
R Driving style
R Tire inflation pressure
R Distance driven
Tread depth G
Warning!
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the

treadwear 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.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Do not allow your tires to wear down too far.
Adhesion properties on wet roads are sharply
reduced at tread depths of less than 1
/ 8 in
(3 mm).
Treadwear indicators (TWI) are required by
law. These indicators are located in six places
on the tread circumference and become
visible at a tread depth of approximately
1 / 16 in (1.6 mm), at which point the tire is
considered worn and should be replaced.
The recommended minimum tire tread depth
for summer tires is 1
/ 8 in (3 mm). The Tires and wheels
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Tire size designation, load and speed
rating
:
Tire width
; Aspect ratio in %
= Radial tire code
? Rim diameter
A Load index
B Speed symbol
i For illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
General: Depending on the design standards
used, the tire size molded into the sidewall
may have no letter or a letter preceding the
tire size designation.
No letter preceding the size designation (as
illustrated above): Passenger car tire based
on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.
Tire width
Tire width : indicates the nominal tire width
in millimeters. Aspect ratio
Aspect ratio
; is the dimensional
relationship between tire section height and
section width and is expressed in percentage.
The aspect ratio is arrived at by dividing
section height by section width.
Tire code
Tire code = indicates the tire construction
type. The “R” stands for radial tire type. Letter
“D” means diagonal or bias ply construction;
letter “B” means belted-bias ply construction.
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR 18). For
additional information, see “Tire speed
rating” (Y page 246).
Rim diameter
Rim diameter ? is the diameter of the bead
seat, not the diameter of the rim edge. The
rim diameter is indicated in inches (in).
Load index G
Warning!
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
tire failure may be the result which may cause
an accident and/or serious injury to you or
others.
Always replace rims and tires with the same
designation, manufacturer and type as shown
on the original part. G
Warning!
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Load index A is a numerical code associated
with the maximum load a tire can support. Tires and wheels
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radio, and heater, to the extent that these
items are available as factory-installed
equipment (whether installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire. Air
pressure is expressed in pounds per square
inch (psi), kilopascal (kPa), or bar.
Aspect ratio
Dimensional relationship between tire
section height and section width expressed
in percentage.
Bar
Metric unit for air pressure. There are
14.5038 pounds per square inch (psi) to
1
bar; there are 100 kilopascals (kPa) to 1 bar.
Bead The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle has
been sitting for at least 3 hours or driven no
more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with standard
equipment including the maximum capacity
of fuel, oil, and coolant, and, if so equipped,
air conditioning and additional optional
equipment, but without passengers and
cargo.
DOT (Department of Transportation)
A tire branding symbol which denotes the tire
meets requirements of the U.S. Department
of Transportation. GAWR (Gross Axle Weight Rating) The GAWR is the maximum permissible axle
weight.

The gross vehicle weight on each axle
must never exceed the GAWR for the front
and rear axle indicated on the certification
label located on the driver’s door B-pillar.
GTW (Gross Trailer Weight) The GTW is the weight of the trailer plus the
weight of all cargo, equipment, luggage etc.
loaded on the trailer.
GVW (Gross Vehicle Weight)
The GVW comprises the weight of the vehicle
including fuel, tools, spare wheel, installed
accessories, passengers and cargo and, if
applicable,

trailer tongue load. The GVW must
never exceed the GVWR indicated on the
certification label located on the driver’s door
B-pillar.
GVWR (Gross Vehicle Weight Rating) This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the

vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa) Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire. Tires and wheels
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Tread
The portion of a tire that comes into contact
with the road.
Treadwear indicators
Narrow bands, sometimes called “wear bars”
that
show across the tread of a tire when only
1 / 16 in (1.6 mm) of tread remains.
TWR (Tongue Weight Rating) Maximum permissible weight on trailer
tongue.
Uniform

Tire Quality Grading Standards A tire information system that provides
consumers with ratings for a tire’s traction,
temperature and treadwear. Ratings are
determined by tire manufacturers using U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
Vehicle maximum load on the tire
Load on an individual tire that is determined
by distributing to each axle its share of the
maximum

loaded vehicle weight and dividing
it by two. Winter driving
General information
Have
your vehicle winterized at an authorized
Mercedes-Benz Center.
i Vehicles with diesel engine:
Do not cover the radiator, for example with
a winter front. Otherwise the readings of
the on-board diagnostic system may be
inaccurate. Some of theses readings are
required by law and must be accurate at all
times. Winter tires
G
Warning!
Winter tires with a tread depth of less than
1 / 6 in (4 mm) must be replaced. They are no
longer suitable for winter operation. G
Warning!
If you use your spare wheel when winter tires
are fitted on the other wheels, be aware that
the

difference in tire characteristics may very
well impair turning stability and that overall
driving stability may be reduced. Adapt your
driving style accordingly.
Have the spare wheel replaced by a regular
road wheel with a winter tire at the nearest
authorized Mercedes-Benz Center.
Always use winter tires at temperatures
below 45‡ (7†) and whenever wintry road
conditions prevail. Not all M+S rated tires
provide special winter performance. Make
sure the tires you use show the mountain/
snowflakeimarking on the tire sidewall.
These tires meet specific snow traction
performance requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC) and
have been designed specifically for use in
snow conditions. Use of winter tires is the
only way to achieve the maximum
effectiveness of your vehicle’s driving safety
systems such as the ABS and the ESP ®
in
winter operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
For information on winter tires for your
vehicle model, see the “Technical data”
section ( Y page 347).
Always observe the speed rating of the winter
tires installed on your vehicle. Winter driving
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Snow chains
! Vehicles with Adaptive Damping System
(ADS):
When driving with snow chains, do not
select SPORT mode as this may result in
damage to your vehicle.
! Some tire sizes do not leave adequate
clearance for snow chains. To help avoid
serious damage to your vehicle or tires,
make sure the use of snow chains is
permissible as specified in the “Technical
data” section of this Operator’s Manual.
Snow chains should only be driven on snow-
covered roads at speeds not to exceed
30 mph (50 km/h)
. Remove chains as soon
as possible when driving on roads without
snow.
Observe the following guidelines when using
snow chains:
R Use of snow chains is not permissible with
all wheel/tire combinations ( Y page 347).
R Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
! If snow chains are mounted to the front
wheels, they may scrape against the body
or axle components. The tires or the vehicle
could be damaged as a result.
R Only use snow chains that are approved by
Mercedes-Benz. Any authorized Mercedes-
Benz Center will be glad to advise you on
this subject.
R Use of snow chains may be prohibited
depending on location. Always check local
and state laws before installing snow
chains.
R Do not use snow chains on the spare wheel.
i When driving with snow chains, you may
wish to switch off the ESP ®
(Y page 65)
before setting the vehicle in motion. This
will improve the vehicle’s traction. Winter driving instructions
G
Warning!
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monoxide
(CO) gases may enter vehicle interior
resulting in unconsciousness and death.
To

assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind. G
Warning!
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. G
Warning!
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.
The most important rule for slippery or icy
roads is to drive sensibly and to avoid abrupt
acceleration, braking and steering
maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding, shift
the automatic transmission to neutral
position N. Try to keep the vehicle under
control by corrective steering action.
i For information on driving with snow
chains, see “Snow chains” ( Y page 252).
Road salts and chemicals can adversely
affect braking efficiency. Increased pedal
force may become necessary to produce the
normal brake effect.
Depressing the brake pedal periodically when
traveling at length on salt-strewn roads can 252
Winter driving
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