tires Lexus IS250 2008 Using the audio system / LEXUS 2008 IS250 (OM53699U) User Guide

Maintenance and care4
273
4-1. Maintenance and care ............................... 274
Cleaning and protecting the vehicle exterior.............. 274
Cleaning and protecting the vehicle interior .............. 277
4-2. Maintenance .................. 280 Maintenance requirements ....................... 280
General maintenance ......... 282
Emission inspection and maintenance (I/M)
programs............................... 285
4-3. Do-it-yourself maintenance ................ 286
Do-it-yourself service precautions ........................... 286
Hood ......................................... 289
Positioning a floor jack ......... 290
Engine compartment............ 292
Tires ............................................ 306
Tire inflation pressure ............ 316 Wheels ...................................... 320
Air conditioning filter ........... 322
Electronic key battery.......... 325
Checking and replacing
fuses ........................................ 327
Headlight aim .......................... 341
Light bulbs ................................ 342

284
4-2. Maintenance
Vehicle exterior
ItemsCheck points
Steering wheel
• Moves smoothly?
• Has correct free play?
• No strange noises?
ItemsCheck points
Door/trunk• Operate smoothly?
Engine hood• The lock system works properly?
Fluid leaks• Is there any leakage after parking?
Ti r e
• Inflation pressure is correct?
• Tire surfaces not worn or dam-aged?
• Tires rotated according to the maintenance schedule?
• Wheel nuts are not loose?
CAUTION
■If the engine is running
Turn the engine off and ensure that there is adequate ventilation before performing
maintenance checks.

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4-3. Do-it-yourself maintenance
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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4-3. Do-it-yourself maintenance
4
Maintenance and care
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 tr ansmitters to detect low tire infla-
tion pressure before serious problems arise. ( P. 362, 370)
Tire size of turning directional tires
Front225/45R17 90W
Rear245/45R17 95W

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4-3. Do-it-yourself maintenance
Installing tire pressure warning valves and transmittersWhen replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning va lves and transmitters are installed,
new tire pressure warning valve and transmitter ID codes must be regis-
tered in the tire pressure warning computer and 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 on vehicles differing with front and rear tire
inflation pressures.
● When changing the ti re inflation pressure by changing traveling
speed.
● When changing the tire size.
When the tire pressure warning sy stem is initialized, the current tire
inflation pressure is set as the pressure benchmark.

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4-3. Do-it-yourself maintenance
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 ti res 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 inst alled on the vehicle is registered.
“2ND” position:The ID code is not registered. When you replace a
new set of tires, purchase tire pres sure warning valves and transmitters
from your Lexus dealer and have th e 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 warnin g system will not operate properly.
After driving for about 20 minutes, the tire pressure warning light
comes on after blinking for 1 minu te 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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4-3. Do-it-yourself maintenance
4
Maintenance and care
■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 warn ing valve and transmitter is not registered,
the tire pressure warning system will not work properly. After driving for about 20
minutes, the tire pressure warning light comes on after blinking for 1 minute to indi-
cate 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 used 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 co mpared 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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4-3. Do-it-yourself maintenance
■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 adequa te traction performance compared with
snow tires in heavy or loos e snow. Also, all 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 ic y 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 loca l 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 inflatio n 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 warnin g 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 carrying out the initialization proc edure, the tire pressure warning light
blinks for 1 minute then stays on after driving for about 20 minutes.

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4-3. Do-it-yourself maintenance
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents. Failure to do so may cause
damage to parts of the drive train, as well as dangerous handling characteristics,
which may lead to fatal or injury accidents.
●Do not mix tires of different makes, models, tread patterns or treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix radial, bias-belted, or bias-ply tires.
●Do not mix summer, all season and winter tires.
■When initializing the tire pressure warning system
Do not press the satellite switch without first adjusting the tire inflation pressure to
the specified level. Otherwise, the tire pressure warning light may not come on
even if the tire inflation pressure is low, or it may come on when the tire inflation
pressure is actually normal.
NOTICE
■Repairing or replacing tires, wheels and tire pressure warning valves and trans-
mitters
When removing or fitting the wheels, tire s or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and trans-
mitter may be damaged if not handled correctly.
■To avoid damaging the tire pressu re warning valves and transmitters
Do not use liquid sealants on flat tires.

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4-3. Do-it-yourself maintenance
4
Maintenance and care
NOTICE
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or pot holes.
These conditions may cause losses in tire inflation pressure, reducing the cushion-
ing ability of the tires. In addition driving on rough roads may cause damage to the
tires themselves, as well as the vehicle’s wheels and body.
■Low profile tires and wheels
Wheels with profile tires like 17- and 18-inch tires may cause greater damage than
usual to the tire wheel when receiving impact from the road surface. Therefore pay
attention to the following:
●Be sure to use proper tire inflation pressure. If tires are under-inflated, they may
be damaged more severely.
●Avoid pot holes, uneven pavement, curbs and other road hazards.
Failure to do so can lead to severe tire and wheel damage.
■If tire inflation pressures become low while driving
Do not continue driving, or your tires and/or wheels may be ruined.