295 Operation
Tires and wheels
Switch on the ignition (
page 34).
Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu
appears in the multifunction display
(page 137).
Press buttonj ork repeatedly
until the current tire inflation pressures
for each tire appear in the multifunc-
tion display.
iAfter you have reactivated the tire infla-
tion pressure monitor, the current tire
inflation pressures will only be shown
after a few minutes’ driving time.
During this time, you will see the follow-
ing message in the multifunction dis-
play:TIRE PRES. DISPLAY
APPEARS AFTER
DRIVING A FEW
MINUTESiPossible differences between the
readings of a tire inflation pressure
gauge of an air hose, e.g. gas station
equipment, and the vehicle’s control
system can occur. The readings issued
by the control system are more pre-
cise.
iYou can select the unit of measure
(Bar/Psi) used for the tire inflation
pressure by changing the setting in the
control system (
page 158).
Warning!
G
When the tire inflation pressure monitoring
system warning light is lit, one or more of
your tires is significantly under-inflated. You
should stop and check your tires as soon as
possible, and inflate them to the proper tire
inflation pressure as indicated on the vehi-
cle’s tire information placard. Driving on a
significantly under-inflated tire causes the
tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping ability. Each tire,
including the spare, should be checked
monthly when cold and set to the recom-
mended tire inflation pressure as specified
in the vehicle placard and owner’s manual.
296 OperationTires and wheels
iThe recommended tire inflation pres-
sures for your vehicle can be found on
the tire placard located on the driver’s
door B-pillar. The tire inflation pres-
sures are not listed in the owner’s man-
ual.Warning!
G
The tire inflation pressure monitor does not
indicate a warning for wrongly selected tire
inflation pressures. Always adjust tire infla-
tion pressure according to the placard on
the driver’s door B-pillar or, if available, the
inside of the fuel filler flap.
The tire inflation pressure monitor is not
able to issue a warning due to a sudden dra-
matic loss of tire inflation 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.
iOperating radio transmission equip-
ment (e.g. wireless headsets, two-way
radios) in or near the vehicle could
cause the tire inflation pressure moni-
tor to malfunction.
Warning!
G
Follow recommend 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 over-
heated.
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.
Do not overload the tires by exceeding the
specified load limit or vehicle capacity
weight as indicated on the placard on the
driver’s door B-pillar (
page 286). Over-
loading the tires can overheat them, possi-
bly causing a blowout.
297 Operation
Tires and wheels
Reactivating the tire inflation pressure
monitor
The tire inflation pressure monitor must be
reactivated in the following situations:
if you have changed the tire inflation
pressure
if you have replaced the wheels or tires
if you have installed new wheels or
tires
Using the tire placard on the driver’s
door B-pillar or, if available, the inside
of the fuel filler flap, make sure the tire
inflation pressure of all four tires is cor-
rect.
Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu
appears in the multifunction display
(page 137).
Press button j or k repeatedly
until you see the current tire inflation
pressures for each tire appear in the
multifunction display or the following
message appears in the multifunction
display:TIRE PRES. DISPLAY
APPEARS AFTER
DRIVING A FEW
MINUTES
Press the reset buttonJon the in-
strument cluster (
page 134).The following message will appear in
the multifunction display:
MONITOR CURRENT
TIRE
PRESSURES?
Press the æ button.
The following message will appear in
the multifunction display:TIRE PRES. MONITOR
REACTIVATED The tire inflation pressure monitor will
now monitor the tire inflation pressure
values of all four tires.
The following message will appear in
the multifunction display:TIRE PRES. DISPLAY
APPEARS AFTER
DRIVING A FEW
MINUTESThis display appears until the individual
tire inflation pressure values are
matched with the tires. The individual
values are then displayed
(page 295).
iIf you are transporting a deflated tire in
the vehicle, do not activate the tire
inflation pressure monitor until
the deflated tire is no longer in the
vehicle
you have inflated the tire to the
correct tire inflation pressure
298 OperationTires and wheelsIf you wish to cancel activation:
Press the ç button.
If one of the following messages appears in
the multifunction display:
TIRE PRES. MONITOR
REACTIVATE AFTER
CORRECTING PRESSURE
TIRE PRESSURE
PLEASE CORRECT
Check the tire inflation pressures and
correct them if necessary.
Reactivate the tire inflation pressure
monitor.Potential problems associated with
underinflated and overinflated tires
Underinflated tire inflation pressure
Underinflated tires can:
cause excessive and uneven tire wear
adversely affect fuel economy
lead to tire failure from being
overheated
adversely affect handling
characteristicsOverinflated tire inflation pressure
Overinflated tires can:
adversely affect handling
characteristics
cause uneven tire wear
be more prone to damage from road
hazards
adversely affect ride comfort
increase stopping distance
Warning!
G
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.
Warning!
G
Follow recommended tire inflation
pressures.
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.
306 OperationTires and wheelsMaximum tire inflation pressure
1Maximum permissible tire inflation
pressure
This is the maximum permissible tire
inflation pressure for the tire.Always follow the recommended tire
inflation pressure (
page 292) for proper
tire inflation. Uniform Tire Quality Grading Standards
(U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistance
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
Warning!
G
Never exceed the max. tire inflation
pressure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and / or unevenly, adverse-
ly 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 com-
fort, wear unevenly, increase stopping dis-
tance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road de-
bris, potholes etc.
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
309 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, 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), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another 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 driv-
en no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
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.
GVW (G
ross V
ehicle W
eight)
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 GWV must never exceed the
GWVR indicated on the Certification label
located on the driver’s door B-pillar.
310 OperationTires and wheelsGVWR (G
ross V
ehicle W
eight R
ating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passen-
gers, fuel, and cargo and, if applicable,
trailer tongue load). It is indicated on
Certification label located on the driver’s
door B-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kilopascals (kPa) to 1 psi; another
metric unit for air pressure is bars. There
are 100 kilopascals (kPa) to 1 bar.
Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
vehicle capacity weight and production
options weight.Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.PSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure
listed on placard located on driver’s door
B-pillar for normal driving conditions.
Provides best handling, tread life and
riding comfort.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
331 Practical hints
What to do if …?
Problem
Possible cause/consequence
Suggested solution
?(USA only)±(Canada only)
The yellow engine malfunc-
tion indicator lamp comes
on while driving.
A loss of pressure has been detected in the
fuel system. The fuel cap may not be closed
properly or the fuel system may be leaky.
Check the fuel cap (
page 270).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an
authorized Mercedes-Benz Center.
The yellow fuel tank reserve warning lamp
comes on while driving.
The fuel level has gone below the reserve
mark.
Refuel at the next gas station
(page 270).