2005 MERCEDES-BENZ E55AMG tire pressure

321 Operation
Tires and wheels
Placard (Example B)
1Vehicle Tire Information placard with
recommended cold tire inflation
pressures
Placard (Example B) lists the recommend-
ed cold tire inflation pressures for maxi-
mum loaded vehicle weight. The tire
inflation pressures listed apply to the tires
installed as original equipment.Important notes on tire inflation
pressure
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.
If you will be driving your vehicle at high
speeds of 100 mph (160 km / h) or higher,
where it is legal and conditions allow,
consult the placard on the inside of the fuel
filler flap on how to adjust the cold tire in-
flation pressure. If you do not adjust the
tire inflation pressure, excessive heat can
build up and result in sudden tire failure.Be sure to readjust the tire inflation
pressure for normal driving speeds. You
should wait until the tires are cold before
adjusting the tire inflation pressure.
Some vehicles may have supplemental tire
pressure information for vehicle loads less
than the maximum loaded vehicle condi-
tion. If such information is provided, it can
be found on the placard located on the in-
side of the fuel filler flap.
Tire inflation pressure changes by approxi-
mately 1.5 psi (0.1 bar) per 18°F (10°C) of
air temperature change. Keep this in mind
when checking tire inflation pressure
where the temperature is different from
the outside temperature.
iPlacard (Example B) may list
recommended cold tire inflation
pressures for different vehicle loads.
Warning!
G
If the tire inflation pressure repeatedly
drops:

Check the tires for punctures from
foreign objects.


Check to see whether air is leaking from
the valves or from around the rim.

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.

328 OperationTires and wheelsGeneral:
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
The tire width1 (
page 327) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (page 327) 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
The tire code3 (
page 327) indicates
the tire construction type. The “R” stands
for radial tire type. Letter “D” means diag-
onal 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” (
page 329).Rim diameter
The rim diameter4 (
page 327) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Tire load rating
The tire load rating5 (page 327) is a
numerical code associated with the
maximum load a tire can support.
For example, a load rating of 91 corre-
sponds to a maximum load of 1 356 lbs
(615 kg) the tire is designed to support.
See also “Maximum tire load”
(
page 333) where the maximum load as-
sociated with the load index is indicated in
kilograms and lbs.