
responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level at which the low tire
pressure indicator lamp of the TPMS lights up.
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 indicator lamp. When the
system detects a malfunction, the indicator
lamp will flash for approximately 1 minute and
then remain illuminated. This sequence will
continue upon subsequent vehicle start-ups
as long as the malfunction exists. When the
malfunction indicator is lit, 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 indicator 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 the tire pressure monitoring system
malfunctions, it may take up to 10 minutes
before the malfunction is displayed to you
by the tire pressure warning lamp flashing
for 60 seconds and then remaining lit.
When the error has been rectified, the tire
pressure warning lamp goes out after a few
minutes of driving.
Information on tire pressures is displayed in
the multifunction display. After a few minutes
of driving, the current tire pressure of each
tire is shown in the multifunction display.
i The tire pressure values in the on-board
computer may deviate from the inflation
pressure as measured using a tire pressure
checker at the filling station. The tire
pressures shown in the on-board computer
refer to pressures at sea level. At highaltitudes, a tire pressure checker will
display a higher tire pressure than the on-
board computer. In this case do not reduce
the tire pressure.
i If radio transmitting equipment (e.g. radio
headphones, a two-way radio) is operated
in or near the vehicle, this can lead to the
function of the tire pressure monitor being
impaired.
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 withstand any
interference received, including
interference that may cause undesired
operation.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Checking the tire pressure
electronicallyXMake sure that the key is in position
2 (Y page 147) in the ignition lock.XPress and hold the V or U button on
the multifunction steering wheel until the
standard display appears in the
multifunction display ( Y page 218).XPress and hold the & or * button
until the current tire pressure of each tire
is shown in the multifunction display.
If the vehicle has been parked for longer than
20 minutes and subsequently you have not
driven faster than 15 mph (25 km/h), the
Tire pressure displayed after
driving for a few minutes message is
shown.
After a teach-in process, the tire pressure
monitor automatically detects new wheels or
new sensors. As long as it is not possible to
allocate tire pressure values to individual
wheel positions, the Tire Pressure
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Monitor Active message appears instead
of the tire pressure display. The tire pressures
are already being monitored.
i If a spare wheel is installed, the system
may continue to show the tire pressure of
the wheel that has been removed for a few
minutes. If this occurs, note that the value
displayed for the position where the
emergency spare wheel/spare wheel is
installed is not the same as the current tire
pressure for the spare wheel.
TPMS warning messages
If the TPMS detects a significant pressure
loss on one or more tires, a warning message
is shown in the multifunction display. In
addition, a warning tone sounds and the tire
pressure warning lamp lights up in the
instrument cluster.
Each tire in which a significant pressure loss
has been detected is highlighted with a red
triangle.
Restarting the tire pressure monitoring
system
GWarning
It is the driver's responsibility to set the tire
inflation pressure to the recommended cold
tire inflation pressure. Underinflated tires
affect the ability to steer or brake the vehicle.
You might lose control over the vehicle.
When you restart the TPMS, all existing
warning messages are deleted and the
warning lamps go out. The currently set tire
pressures are adopted as the specified values
for monitoring.
The TPMS must be restarted when you set the
tire pressure to a new value (as a result of
changed handling or load characteristics, for
example). The TPMS then monitors the new
tire pressure values.
Restart the TPMS after the tire pressure has
been set, as desired, according to the
recommended values for the driving
conditions ( Y page 336). Only correct tire
pressures on cold tires. Comply with the tire
pressures recommended on the Tire and
Loading Information placard on the B-pillar on
the driver's side. Additional tire pressure
values for driving at high speeds or with heavy
loads can be found in the tire pressure table
on the inside of the fuel filler flap.XMake sure that the tire pressure is set
properly in all four tires.XMake sure that the key is in position 2 in
the ignition lock.XPress and hold the V or U button on
the multifunction steering wheel until the
standard display appears in the
multifunction display ( Y page 218).XPress and hold the & or * button
until the tire pressure of all tires or the
Tire pressure displayed after
driving for a few minutes. message
is shown.XPress the reset button on the instrument
cluster ( Y page 28).
The Restart tire pressure monitor?
Yes Cancel message appears in the
multifunction display.XTo confirm selection: press the W
button.
The Tire Pressure Monitor
Restarted message appears in the
multifunction display.
After driving for a few minutes, the system
confirms that the current tire pressure
values are within the specified range. The
new tire pressure values are then accepted
as reference values and monitored.XTo cancel restart: press the X button.
i
If the positions of the wheels on the
vehicle have been changed, the tire
pressure may be shown in the wrong
position briefly. This will be corrected after
driving for a few minutes and the tire
pressure will be displayed in the correct
position.
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Maximum tire pressuresGWarning
Never exceed the maximum tire inflation
pressure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
:Maximum permitted tire pressure
(example)
i The actual values for tires are specific to
each vehicle and may deviate from the
values in the illustration.
When adjusting the tire pressures always
observe the recommended tire pressure for
your vehicle ( Y page 336).
Loading the vehicle
Instruction labels for tires and loads
GWarning
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.
Two instruction labels on your vehicle show
the maximum possible load.(1)The Tire and Loading Information placard
on the B-pillar on the driver's side. the
Tire and Loading Information placard
shows the maximum possible number of
occupants and the maximum possible
vehicle load. It also contains details of the
tire sizes and corresponding pressures
for tires installed at the factory.(2)The vehicle identification plate is on the
B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight rating. It is made up
of the vehicle weight, all vehicle
occupants, the fuel and the cargo. You
can also find information about the
maximum gross axle weight rating on the
front and rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried
by one axle (front or rear axle). Never
exceed the maximum load or the
maximum gross axle weight rating for the
front or rear axle.344Loading the vehicleTires and wheels
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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 316).
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 354);DOT, Tire Identification Number
( Y page 353)=Maximum tire load ( Y page 348)?Maximum tire pressure ( Y page 344)AManufacturerBTire material ( Y page 354)CTire size designation, load-bearing
capacity and speed index ( Y page 351)DLoad index ( Y page 353)ETire name
i
Tire data is vehicle-specific and may
deviate from the data in the example.
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Tire size designation, load-bearing
capacity and speed index:Tire width;Aspect ratio in percent=Tire code?Rim diameterALoad bearing indexBSpeed index
i Tire data is vehicle-specific and may
deviate from the data in the example.
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size
description (as shown above): passenger
vehicle tires according to European
manufacturing standards.
If "P" precedes the size description:
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: light
truck tires according to U.S. manufacturing
standards.
If "T" precedes the size description: compact
emergency spare wheels at high tire
pressure, only for temporary use in an
emergency.
Tire width: tire width : shows the nominal
tire width in millimeters.
Aspect ratio: aspect ratio ; is relationship
between tire height and tire width and is
specified in percent. The aspect ratio is
calculated by dividing the tire width by the tire
height.
Tire code: tire code = specifies the tire type.
"R" represents radial tires. "D" represents
diagonal tires, "B" represents diagonal radial
tires.
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).
Rim diameter: rim diameter ? is the
diameter of the bead seat, not the diameter
of the rim flange. The rim diameter is
specified in inches (in).
Load bearing index: load bearing index A
is a numerical code that specifies the
maximum load-bearing capacity of a tire.GWarning
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
sudden tire failure may be the result which
could cause an accident and/or serious injury
to you or others.
Always replace rims and tires with rims and
tires having the same specifications
(designation, manufacturer and type) as
shown on the original part.
GWarning
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.
Example:
The load bearing index 91 is equivalent to a
maximum load of 1356 lbs (615 kg) that the
tire can carry. For further information on the
maximum tire load in kilograms and pounds,
see ( Y page 348).
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have been especially developed for driving
on snow.
An electronic speed limiter prevents your
vehicle from exceeding a speed of
130 mph (210 km/h).
The speed index of tires installed at the
factory may be higher than the maximum
speed that the electronic speed limiter
permits.
Make sure that your tires have the required
speed index as specified in the "Tires" section
( Y page 357) for your vehicle, e.g. when
buying new tires.
More information on reading the tire data can
be obtained at any qualified specialist
workshop, e.g. at an authorized Mercedes-
Benz Center.
Load index
i Tire data is vehicle-specific and may
deviate from the data in the example.
In addition to the load bearing index, load
index : may be imprinted after the letters
that identify speed index B (Y page 351) on
the sidewall of the tire.
R If no specification is given: no text (as in the
example above), represents a standard
load (SL) tire
R XL or Extra Load: represents a reinforced
tire
R Light load: represents a light load tire
R C, D, E: represents a load range that
depends on the maximum load that the tire
can carry at a certain pressure
DOT, Tire Identification Number (TIN)
U.S. tire regulations prescribe that every new
tire manufacturer or retreader has to imprint
a TIN in or on the sidewall of each tire
produced.
The TIN is a unique identification number. The
TIN enables the tire manufacturers to inform
purchasers of recalls and other safety-
relevant matters. It makes it possible for the
purchaser to easily identify the affected tires.
The TIN is made up of manufacturer
identification code ;, tire size =, tire type
code ? and date of manufacture A.
i Tire data is vehicle-specific and may
deviate from the data in the example.
DOT (Department of Transportation): tire
symbol : marks that the tire complies with
the requirements of the U.S. Department of
Transportation.
Manufacturer identification code:
manufacturer identification code ; provides
details on the tire manufacturer. New tires
have a code with two symbols. Retreaded
tires have a code with four symbols.
Further information about retreaded tires
( Y page 334).
Tire size: identifier = describes the tire size.
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Tire type code: tire type code ? can be
used by the manufacturer as a code to
describe specific characteristics of the tire.
Date of manufacture: date of manufacture
A provides information about the age of a
tire. The first and second positions represent
the week of manufacture, starting with "01"
for the first calendar week. Positions three
and four represent the year of manufacture.
For example, a tire that is marked with
"3208", was manufactured in week 32 in
2008.
Characteristics of the tire
i Tire data is vehicle-specific and may
deviate from the data in the example.
This information describes the tire cord and
the number of layers in sidewall : and under
tire tread ;.
Definitions for tires and loading
Structure and condition of the tire
Describes the number of layers or the number
of rubber-coated belts in the tire tread and
the tire wall. These are made of steel, nylon,
polyester and other materials.
Bar
Metric unit for tire pressure. 14.5038 pounds
per square inch (psi) and 100 kilopascals
(kPa) are the equivalent of 1 bar.
DOT (Department of Transportation)
DOT marked tires fulfill the requirements of
the United States Department of
Transportation.
Average weight of the vehicle
occupants
The number of occupants for which the
vehicle is designed multiplied by 68 kilograms
(150 lb).
Uniform Tire Quality Grading
Standards
A uniform standard to grade the quality of
tires with regards to tread quality, tire traction
and temperature characteristics. The quality
grading assessment is made by the
manufacturer following specifications from
the U.S. government. The quality grade of a
tire is imprinted on the sidewall of the tire.
Recommended tire pressure
The recommended tire pressure for your
vehicle under normal driving conditions. You
will find the recommendation on the Tire and
Loading Information placard on the B-pillar on
the driver's side of your vehicle. The
recommended tire pressure provides the best
balance between handling characteristics,
ride comfort and wear. Additional information
on particular driving conditions is located on
the tire pressure table on the inside of the fuel
filler flap.
Increased vehicle weight due to
optional equipment
The combined weight of all standard and
optional equipment available for the vehicle,
regardless of whether it is actually installed
on the vehicle or not.
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Wheel rim
The part of the wheel on which the tire is
mounted.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side.
Speed index
The speed index is part of the tire
identification. Specifies the speed range for
which the tire is approved.
GTW (Gross Trailer Weight)
The GTW is the weight of a trailer including
the weight of the load, luggage, accessories
etc. on the trailer.
GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight
of the vehicle including fuel, tools, the spare
wheel, accessories installed, occupants,
luggage and the drawbar noseweight if
applicable. The gross vehicle weight must not
exceed the gross vehicle weight rating GVWR
as specified on the vehicle identification plate
on the B-pillar on the driver's side.
GVWR (Gross Vehicle Weight Rating)
The GVWR is the maximum permissible gross
weight of a fully loaded vehicle (the weight of
the vehicle including all accessories,
occupants, fuel, luggage and the drawbar
noseweight if applicable). The gross vehicle
weight rating is specified on the vehicle
identification plate on the B-pillar on the
driver's side.
Maximum weight of the laden vehicle
The maximum weight is the sum of the
unladen weight of the vehicle, the weight of
the accessories, the maximum load and the
weight of the optional equipment installed at
the factory.
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa is the
equivalent of 1 psi. Another unit for tire
pressure is bar. 100 kilopascal (kPa) is the
equivalent of 1 bar.
Load index
In addition to the load bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load bearing
capacity more precisely.
Unladen weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed on the vehicle, but does
not include passengers or luggage.
Maximum tire load
The maximum tire load in kilograms or
pounds is the maximum weight for which a
tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
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