
vehicle to a halt by braking carefully. Avoid
abrupt steering maneuvers.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating a pressure loss or malfunction.
Whether the warning lamp flashes or lights up
indicates whether a tire pressure is too low or
the tire pressure monitor is malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is
significantly too low. The tire pressure
monitor is not malfunctioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
i In addition to the warning lamp, a
message appears in the multifunction
display.
Further information can be found on
(Y page 280).
If the tire pressure monitor is malfunctioning,
it may take more than ten minutes for the tire
pressure warning lamp to inform you of the
malfunction by flashing for approximately one
minute and then remaining lit. When the
malfunction has been rectified, the tire
pressure warning lamp goes out after a few
minutes of driving.
The tire pressure values indicated by the on-
board computer may differ from those
measured at a gas station with a pressure
gauge. The tire pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tire pressure
values indicated by a pressure gauge are
higher than those shown by the on-board
computer. In this case, do not reduce the tire
pressures.
The operation of the tire pressure monitor can
be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle. Checking the tire pressure
electronically X
Make sure that the SmartKey is in position
2in the ignition lock (Y page 159).
X Press the =or; button on the
steering wheel to select the Service Service
menu.
X Press the 9or: button to select
Tire Pressure
Tire Pressure.
X Press the abutton.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle has been parked for over
20 minutes, the Tire Tirepressures
pressures will
willbe
be
displayed after driving a few
displayed after driving a few
minutes minutes message appears.
After a teach-in process, the tire pressure
monitor automatically detects new wheels or
new sensors. As long as a clear allocation of
the tire pressure value to the individual
wheels is not possible, the Tire Pressure Tire Pressure
Monitor Active
Monitor Active display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
i If an emergency spare wheel is mounted,
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 spare wheel is mounted
is not the same as the current tire pressure
of the emergency spare wheel.
Tire pressure monitor warning
messages If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message
is shown in the multifunction display and the
yellow tire pressure monitor warning lamp
comes on.
R
If the Correct Tire Pressure Correct Tire Pressure message
appears in the multifunction display, the
tire pressure in at least one tire is too low 382
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Tire labeling
Overview :
Uniform Tire Quality Grading Standard
(Y page 393)
; DOT, Tire Identification Number
(Y page 392)
= Maximum tire load (Y page 391)
? Maximum tire pressure (Y page 378)
A Manufacturer
B Tire material (Y page 392)
C Tire size designation, load-bearing
capacity and speed index (Y page 389)
D Load index (Y page 391)
E Tire name
The markings described above are on the tire
in addition to the tire name (sales
designation) and the manufacturer's name.
i Tire data is vehicle-specific and may
deviate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating G
WARNING
Exceeding the stated tire load-bearing
capacity and the approved maximum speed
could lead to tire damage or the tire bursting.
There is a risk of accident. Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle.
:
Tire width
; Nominal aspect ratio in %
= Tire code
? Rim diameter
A Load bearing index
B Speed rating
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): these are
passenger vehicle tires according to
European manufacturing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S.
manufacturing standards.
If "T" precedes the size description: these are
compact emergency spare wheels at high tire
pressure, to be used only temporarily in an
emergency.
Tire width: tire width:shows the nominal
tire width in millimeters.
Aspect ratio: aspect ratio;is the size ratio
between the tire height and tire width and is
shown in percent. The aspect ratio is All about
wheels and tires
389Wheels and tires Z
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All-weather tires and winter tires
Index Speed rating
Q M+S
1 up to 100 mph (160 km/h)
T M+S
1 up to 118 mph (190 km/h)
H M+S
1 up to 130 mph (210 km/h)
V M+S
1 up to 149 mph (240 km/h)
i
Not all tires with the M+S marking provide
the driving characteristics of winter tires.
In addition to the M+S marking, winter tires
also have the isnowflake symbol on
the tire wall. Tires with this marking fulfill
the requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC)
regarding the tire traction on snow. They
have been especially developed for driving
on snow.
An electronic speed limiter prevents your
vehicle from exceeding the following speeds:
R all vehicles (except AMG vehicles):
130 mph (210 km/h)
R AMG vehicles: 155 mph (250 km/h)
R AMG vehicles with Performance Package
(Wagon): 174 mph (280 km/h)
R AMG vehicles with Performance Package
(Sedan): 186 mph (300 km/h)
The speed rating of tires mounted 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 rating, e.g. when buying new tires. The
required speed rating for your vehicle can be
found in the "Tires" section (Y page 400).
Further information about reading tire data
can be obtained from any qualified specialist
workshop. Load index
In addition to the load bearing index, load
index
:may be imprinted after the letters
that identify speed index Bon the sidewall
of the tire (Y page 389).
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
i Tire data is vehicle-specific and may
deviate from the data in the example.
Maximum load rating Maximum tire load
:is the maximum
permissible weight for which the tire is
approved.
1 Or M+S ifor winter tires. All about wheels and tires
391Wheels and tires Z
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Curb 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 in the vehicle, but does
not include passengers or luggage.
Maximum load rating
The maximum tire load is the maximum
permissible weight in kilograms or lbs for
which a tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold.
Cold tire pressure
The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has been driven for less than
1 mile (1.6 km). Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kilograms (5 lbs).
These optional extras, such as high-
performance brakes, level control, a roof rack
or a high-performance battery, are not
included in the curb weight and the weight of
the accessories.
TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identify
the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are
distributed over the tire tread. If the tire tread
is level with the bars, the wear limit of áin
(1.6 mm) has been reached. 394
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Securing the vehicle on slight downhill gradients
(example: Sedan)
X On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate
jacking point of the vehicle. The base of the
jack must be positioned vertically, directly
under the jacking point of the vehicle.
! The jack is designed exclusively for
jacking up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged.
Observe the following when raising the
vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used
incorrectly, the jack could tip over with the
vehicle raised.
R the jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for
performing maintenance work under the
vehicle.
R avoid changing the wheel on uphill and
downhill slopes. R
before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Never
disengage the parking brake while the
vehicle is raised.
R the jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, load-bearing underlay must be used.
On a slippery surface, a non-slip underlay
must be used, e.g. rubber mats.
R do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R make sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm).
R never place your hands and feet under the
raised vehicle.
R never lie under the raised vehicle.
R never start the engine when the vehicle is
raised.
R never open or close a door or the trunk lid/
tailgate when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised.
AMG vehicles with Performance Studio
equipment: the wheel bolts are covered by a
hub cap. Before you are able to unscrew the
wheel bolts, you must first remove the hub
cap. Changing a wheel
397Wheels and tires Z
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Stowing a used collapsible spare
wheel
! Only place the collapsible spare wheel in
the vehicle when it is dry. Otherwise,
moisture may get into the vehicle.
Take the following steps to stow a used
collapsible spare wheel. It will not otherwise
install into the spare wheel well. Mercedes-
Benz recommends that you have this work
performed at a qualified specialist workshop,
e.g. at an authorized Mercedes-Benz Center.
X Unscrew the valve cap from the valve.
X Use the back of the valve cap to unscrew
the valve insert from the valve and release
the air.
i Fully deflating the tires can take a few
minutes.
X Screw the valve insert back into the valve.
X Screw the valve cap back on.
X Remove the protective sheet from the
vehicle tool kit and pull it over the
collapsible spare wheel.
X Stow the collapsible spare wheel in the
emergency spare wheel well under the
trunk. Inflating the collapsible spare wheel
! Inflate the collapsible spare wheel using
the tire inflation compressor before
lowering the vehicle. The wheel rim could
otherwise be damaged.
! Do not operate the tire inflation
compressor for longer than eight minutes
at a time without a break. It may otherwise
overheat.
The tire inflation compressor can be
operated again once it has cooled down. X
Mount the collapsible spare wheel as
described (Y page 395).
The collapsible spare wheel must be
mounted before it is inflated.
X Pull connector ?and the air hose out of
the housing.
X Remove the cap from the valve on the
collapsible spare wheel.
X Screw union nut :on the air hose onto the
valve.
X Make sure on/off switch Aof the tire
inflation compressor is set to 0.
X Insert connector ?into the cigarette
lighter socket or into a 12 V socket in your
vehicle.
Observe the notes on the cigarette lighter
(Y page 319). Observe the notes on
sockets (Y page 320).
X Turn the SmartKey to position 1in the
ignition lock (Y page 159).
X Press on/off switch Aon the tire inflation
compressor to I.
The tire inflation compressor is switched
on. The tire is inflated. The tire pressure is
shown on pressure gauge =.
X Inflate the tire to the specified tire
pressure.
The specified tire pressure is printed on the
yellow label of the emergency spare wheel.
X When the specified tire pressure has been
reached, press on/off switch Aon the
electric air pump to 0.
The tire inflation compressor is switched
off. 412
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