2008 Lexus IS250 tire pressure

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Maintenance and care
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CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury,
observe the following precautions.
■When working on the engine compartment:
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, radiator, exhaust manifold, etc. right after driv-
ing as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel
and battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and
corrosive sulfuric acid.
ItemsParts and tools
Engine oil level (→P. 2 9 5 )
• “Toyota Genuine Motor Oil” or equivalent
• Rag or paper towel, funnel (used
only for adding engine oil)
Fuses (→P. 3 2 7 )• Fuse with same amperage rating as
original
Tire inflation pressure (→P. 316)• Tire pressure gauge
• Compressed air source
Headlight aim (→P. 3 4 1 )• Phillips-head screwdriver
Radiator and condenser (→P. 3 0 1 )
Wa s h e r f l u i d (→P. 3 0 5 )
• Water washer fluid containing anti-freeze (for winter use)
•Funnel

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Tires
Replace or rotate tires in accordance with maintenance schedules and
treadwear.
■Checking tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indi-
cators is shown by the “TWI” or
“
∆” marks, etc., molded on the
sidewall of each tire.
Check spare tire condition and
pressure if not rotated.
■ Tire rotation
2WD models with 16-inch tires and AWD models
Rotate the tires in the order
shown.
To equalize tire wear and extend
tire life, Lexus recommends that
tire rotation is carried out at the
same interval as tire inspection.
Do not fail to initialize the tire
pressure warning system after
tire rotation.
2WD models with 18-inch tiresRotate the tires in the order
shown.
To equalize tire wear and extend
tire life, Lexus recommends that
tire rotation is carried out at the
same interval as tire inspection.
Front
Front

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Directional tiresTire direction marks
The tires listed below are direc-
tional. The tire sidewalls are
marked with arrows indicating the
rolling direction of the tire. If
mounted on the wrong side of the
vehicle, directional tires will per-
form poorly.
2WD models with 17-inch tires
Tires cannot be rotated.
■ The tire pressure warning system
Your Lexus is equipped with a tire pressure warning system that uses
tire pressure warning valves and transmitters to detect low tire infla-
tion pressure before serious problems arise. ( →P. 362, 370)
Tire size of turning directional tires
Front225/45R17 90W
Rear245/45R 1 7 95W

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Installing tire inflation pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning valves and transmitters are installed,
new tire pressure warning valve and transmitter ID codes must be regis-
tered in the tire pressure warning computer and the tire pressure warning
system must be initialized. Have tire pressure warning valve and transmit-
ter ID codes registered by your Lexus dealer. ( →P. 310)
Initializing the tire pressure warning system
■ The tire pressure warning system must be initialized in the following
circumstances:
●When rotating the tires differing with front and rear tire inflation
pressures.
● When changing the tire inflation pressure by changing traveling
speed.
● When changing the tire size.
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the pressure benchmark.

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Maintenance and care
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How to initialize the tire pressure warning system
To initialize the system, use the satellite switch. ( →P. 245)
Park the vehicle in safe place and turn the “ENGINE START
STOP” switch to OFF.
While the vehicle is moving, initialization is not performed.
Adjust the tire inflation pressure to the specified cold tire inflation
pressure level. ( →P. 415)
Make sure to adjust the tire pressure to the specified cold tire inflation
pressure level. The tire pressure warning system will operate based on
this pressure level.
Turn the “ENGINE START STOP” switch to IGNITION ON
mode.
The tire inflation pressure initial-
ization setting display
Continue to press < or > until the
initialization setting display
appears.
It may take several minutes to com-
plete the setting. Wait for several
minutes before turning the
“ENGINE START STOP” switch to
OFF if necessary.
Recording tire inflation pressure
settings
Press and hold the “ON/OFF” but-
ton until the tire pressure warning
light blinks slowly 3 times and the
message “PRESSURE INITIAL”
showing that the initial setting is
complete is displayed on the multi-
information display.
Wait for a few minutes with the IGNITION ON mode, and then
turn the “ENGINE START STOP” switch OFF.
STEP1
STEP2
STEP3
STEP4
STEP5

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Registering and selecting ID codesTo select tire pressure warning valve and transmitter ID codes, use the
satellite switch. ( →P. 245)
■ Registering ID codes
2 sets of tire pressure warning valve and transmitter ID codes can be
registered. Once a second set of tires is registered at “2nd”, you can
switch between tire set settings simply by pressing the tire pressure
warning select switch.
There are 2 settings:
“MAIN” position: The ID code of the tire pressure warning valve and
transmitter on the tires originally installed on the
vehicle is registered.
“2nd” position: The ID code is not registered. When you replace a new set of tires, purchase tire pressure warning valves and
transmitters from your Lexus dealer and have the new
ID code registered by your Lexus dealer.
■ Selecting ID codes
When replacing tires, make sure to select the ID code set that matches
the new tire set. If the tire pressure select switch is set to the wrong tire
setting, the tire pressure warning system will not operate properly.
After about 20 minutes, the tire pressure warning light comes on after
blinking for 1 minute to indicate a system malfunction.
Tire pressure warning valve and
transmitter ID code settings dis-
play
Press < or > repeatedly until the
setting display appears.
Switching ID codes
Press the “ON/OFF” button to
switch between “MAIN” and
“2ND” ID codes.

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■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the
fabric or bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered,
the tire pressure warning system will not work properly. After about 20 minutes, the
tire pressure warning light comes on after blinking for 1 minute to indicate a system
malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if they
have seldom or never been us ed or damage is not obvious.
■If the tread wears down below 0.16 in. (4 mm) on snow tires
The effectiveness of snow tires is lost.
■Low profile tires (models not equipped with 16-inch tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when compared to standard tires. Be sure to
use snow tires or tire chains
* on snowy and/or icy roads and drive carefully at a
speed appropriate for road and weather conditions.
*: Tire chains cannot be mounted on 18-inch tires.
■Maximum load of tire
Check that the maximum load of the replaced tire is greater than 1 /2 of the Gross
Axle Weight Ratings (GAWR) of either the front axle or the rear axle, whichever is
greater.
As for the maximum load of the tire, see the load limit at maximum cold tire inflation
pressure mentioned on the sidewall of the tire, and as for the Gross Axle Weight
Ratings (GAWR), see the Certification Label. (
→P. 3 1 6 , 4 2 4 ) .

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■Tire types
1 Summer tiresSummer tires are high-speed performance tires best suited to highway driving
under dry conditions. Since summer tires do not have the same traction perfor-
mance as snow tires, summer tires are inadequate for driving on snow-covered
or icy roads. For driving on snow-covered roads or icy roads, the use of snow tires
is recommended. When installing snow tires, be sure to replace all four tires.
2 All season tires All season tires are designed to provide better traction in snow and to be ade-
quate for driving in most winter conditions, as well as for use year round. All sea-
son tires, however, do not have adequate traction performance compared with
snow tires in heavy or loose snow. Also, al l season tires fall short in acceleration
and handling performance compared with summer tires in highway driving.
3Snow tires For driving on snow-covered roads or icy roads, we recommend using snow tires.
If you need snow tires, select tires of the same size, construction and load capac-
ity as the originally installed tires. Since your vehicle has radial tires as original
equipment, make sure your snow tires also have radial construction. Do not install
studded tires without first checking local regulations for possible restriction.
Snow tires should be installed on all wheels. (
→P. 1 8 3 )
■Initializing the tire pressure warning system
Initialize the tires with the tire inflation pressure adjusted to the specified level.
■When the initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases,
the settings have not been recorded and the system will not operate properly. If
repeated attempts to record tire inflation pressure settings are unsuccessful, have
the vehicle inspected by your Lexus dealer.
●When operating the tire pressure warning reset switch, the tire pressure warn-
ing light does not flash 3 times and the setting message does not appear on the
multi-information display.
●After driving for a certain period of time since the initialization has been com-
pleted, the tire pressure warning light comes on after blinking for 1 minute.