warning Lexus IS250 2008 Using the air conditioning system and defogger / LEXUS 2008 IS250 (OM53699U) Owner's Guide

307
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

308
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.

309
4-3. Do-it-yourself maintenance
4
Maintenance and care
■How to initialize the tire pressure warning system
To initialize the system, use the satellite switch. ( P. 245)
Park the vehicle in safe plac e and turn the “ENGINE START
STOP” switch 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

310
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.

311
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 ) .

312
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.

313
4-3. Do-it-yourself maintenance
4
Maintenance and care
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
■Tire pressure warning system certificationFor vehicles sold in the U.S.A.
This device complies with Part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) this device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
NOTICE:
This equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential installa-
tion. This equipment generate s, uses and can radiate radio frequency energy and, if
not installed and used in accordance with the instructions, may cause harmful inter-
ference to radio communications. However, there is no guarantee that interference
will not occur in a particular installation. If this equipment does cause harmful inter-
ference to radio or television reception, which can be determined by turning the
equipment off and on, the user is encouraged to try to correct the interference by
one or more of the following measures:
●Reorient or relocate the receiving antenna.
●Increase the separation between the equipment and receiver.
●Connect the equipment into an outlet on a circuit different from that to which
the receiver is connected.
●Consult the dealer or an experienced radio/TV technician for help.
FCC WARNING:
Changes or modifications not expressly approved by the party responsible for
compliance could void the user's authority to operate the equipment.
For vehicles sold in Canada
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must a ccept any interference, including interfer-
ence that may cause undesired operation of the device.

314
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.

320
4-3. Do-it-yourself maintenance
Wheels
■When replacing wheels
The wheels of your Lexus are equipped with tire pressure warning valves and trans-
mitters that allow the tire pressure warning system to provide advanced warning in
the event of a loss in tire inflation pressure. Whenever wheels are replaced, the tire
pressure warning valves and transmitters must be installed. ( P. 3 0 8 )
If a wheel is bent, cracked or heavily corroded, it should be replaced. Oth-
erwise, the tire may separate from the wheel or cause loss of handling con-
trol.
■ Wheel selection
When replacing wheels, care should be taken to ensure that they
are equivalent to those removed in load capacity, diameter, rim
width, and offset.
Replacement wheels are available at your Lexus dealer.
Lexus does not recommend using:
• Wheels of different sizes or types
• Used wheels
• Bent wheels that have been straightened
■ Aluminum wheel precautions
●Use only Lexus wheel nuts and wrenches designed for use with
your aluminum wheels.
● When rotating, repairing or changi ng your tires, check that the
wheel nuts are still tight after driving 1000 miles (1600 km).
● Be careful not to damage the aluminum wheels when using tire
chains.
● Use only Lexus genuine balance weights or equivalent and a
plastic or rubber hammer when balancing your wheels.

321
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■When replacing wheels
●Do not use wheels that are a different size from those recommended in the
Owner’s Manual, as this may result in loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire.
Doing so may result in an accident, causing death or serious injury.
NOTICE
■Replacing tire inflation pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warning valves
and transmitters, make sure to have tires serviced by your Lexus dealer or other
qualified service shop. In addition, make sure to purchase your tire pressure
warning valves and transmitters at your Lexus dealer.
●Ensure that only Genuine Lexus wh eels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly with non-
genuine wheels.