2005 MERCEDES-BENZ E500 inflation pressure

322 OperationTires and wheelsChecking tire inflation pressure
Regularly check your tire inflation pressure
at least once a month.
Check and adjust the tire inflation
pressure when the tires are cold. The tires
can be considered cold if the vehicle has
been parked for at least three hours or
driven less than one mile (1.6 km).
If you check the tire inflation pressure
when the tires are warm (the vehicle has
been driven for several miles or sitting less
than three hours), the reading will be
approximately 4 psi (0.3 bar) higher than
the cold reading. This is normal. Do not let
air out to match the specified cold tire in-
flation pressure. Otherwise, the tire will be
underinflated.
Checking tire inflation pressure
manually
Follow the steps below to achieve correct
tire inflation pressure:
Remove the cap from the valve on one
tire.

Firmly press a tire gauge onto the
valve.

Read tire inflation pressure on tire
gauge and check against the recom-
mended tire inflation pressure on the
placard on the driver’s door B-pillar
(page 315). If necessary, add air to
achieve the recommended tire inflation
pressure.

Install the valve cap.

Repeat this procedure for each tire.Checking tire inflation pressure elec-
tronically*
The tire pressure monitoring system only
functions on wheels that are equipped with
the proper electronic sensors. It monitors
the tire inflation pressure, as selected by
the driver, in all four tires. A warning is is-
sued to alert you to a decrease in pressure
in one or more of the tires.
You can call up the tire inflation pressure
using the control system (
page 150).
iIf you have overfilled the tire, release
tire inflation pressure by pushing the
metal stem of the valve with e.g. a tip of
a pen. Then recheck the tire inflation
pressure with the tire gauge.
iAfter you have reactivated the tire
pressure monitoring system, the cur-
rent 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 display:Tire pressure

displayed only
after driving
a few mins.

323 Operation
Tires and wheels

Switch on the ignition (
page 33).

Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu ap-
pears in the multifunction display
(page 150).

Press the j or k button until the
current inflation pressures for each tire
appear in the multifunction display.iPossible differences between the read-
ings 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 con-
trol system are more precise.
Warning!
G
When the tire 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 possi-
ble, and inflate them to the proper pressure
as indicated on the vehicle’s tire information
placard. Driving on a significantly under-in-
flated 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 vehicle’s handling and
stopping ability. Each tire, including the
spare, should be checked monthly when
cold and set to the recommended inflation
pressure as specified in the vehicle placard
and owner’s manual.iThe recommended tire inflation pres-
sures for your vehicle can be found on
the placard on the driver’s door B-pillar
or the inside of the fuel filler flap, not in
the owner’s manual.
Warning!
G
The tire pressure monitoring system does
not indicate a warning for wrongly selected
inflation pressures. Always adjust tire infla-
tion pressure according to the placard locat-
ed on the driver’s door B-pillar or the inside
of the fuel filler flap.
The tire pressure monitoring system is not
able to issue a warning due to a sudden dra-
matic loss of pressure (e.g. tire blowout
caused by a foreign object). In this case
bring the vehicle to a halt by carefully apply-
ing 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 pressure monitoring sys-
tem to malfunction.

324 OperationTires and wheels
Reactivating the tire pressure monitor-
ing system
The tire pressure monitoring system 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 button j or k repeatedly
until you see the current inflation pres-
sures for each tire appear in the multi-
function display or the following
message appears in the multifunction
display:Tire pressure

displayed only
after driving
a few mins.

Press the reset button on the instru-
ment cluster (
page 24).
The following message will appear in
the multifunction display:
Check current

tire pres.?

Warning!
G
Follow recommended tire inflation pres-
sures.
Do not overinflate tires. Overinflating tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes,
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indicat-
ed by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.
iIf you are transporting a deflated tire in
the vehicle, do not activate the tire
pressure monitoring system until

the deflated tire is no longer in the
vehicle


you have inflated the tire to the cor-
rect pressure

325 Operation
Tires and wheels

Press the æ button.
The following message will appear in
the multifunction display field:Tire pres. monitor

reactivated

The tire pressure monitoring system
will now monitor the tire inflation pres-
sure values of all four tires.
The following message will appear in
the multifunction display field:
Tire pressure

displayed only
after driving
a few mins. This display appears until the individual
inflation pressure values are matched
with the tires. The individual values are
then displayed (
page 396).If you wish to cancel activation:

Press the ç button.
If one of the following messages appears in
the multifunction display:


reactivate tire
pressure monitor
after rectifying
pressure


Tire pressure

Please rectify


Check the tire inflation pressures and
correct them if necessary.

Reactivate the tire pressure monitoring
system.
iAfter you have reactivated the tire
pressure monitoring system, the cur-
rent tire inflation pressure values will
only be shown after several minutes of
driving. During this time, the following
message appears in the display:Tire pressure

displayed only
after driving
a few mins. The time before the tire inflation pres-
sures are shown depends on whether
or not

you have mounted new tires


the old tires are still on the vehicle
If you have mounted new tires, it will
take slightly longer before the tire infla-
tion pressures are shown in the display.

326 OperationTires and wheels
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
iIf the positions of the wheels have not
been changed on the vehicle, the tire
inflation pressures are shown correctly
after a short period. If the positions of
the wheels have been switched, howev-
er, it is possible that the tire inflation
pressures are temporarily shown for
the wrong wheel positions. They are
corrected after a few minutes of driv-
ing, and the tire inflation pressures are
shown for the correct wheel positions.
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.

327 Operation
Tires and wheels
Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle's tires:1Uniform Quality Grading Standards
(
page 334)
2DOT, Tire Identification Number (TIN)
(page 332)
3Maximum tire load (
page 333)
4Maximum tire inflation pressure
(
page 334)
5Manufacturer
6Tire ply material (
page 336)
7Tire size designation, load and speed
rating (
page 327)
8Load identification (
page 331)
9Tire nameTire size designation, load and speed
rating
1Tire width
2Aspect ratio in %
3Radial tire code
4Rim diameter
5Tire load rating
6Tire speed rating
iFor illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.
For more information, see “Rims and
tires” (
page 453).
iFor illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.

334 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 320) 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 is specific to each vehicle
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 is specific to each vehicle
and may vary from data shown in above
illustration.

337 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 three hours or
driven no more than one 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.