
4867-3. Do-it-yourself maintenance
IS350 AWD/IS350/IS300 AWD/IS300_U(OM53E34U)
■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
●You have tire damage such as cuts, splits, cracks deep enough to expose the fabric, and
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 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 proper ly. After driving for about 20 minutes, the
tire pressure warning light blinks for 1 minu te and stays on to indicate a system malfunc-
tion.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has seldom
or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning syst em does not replace routine tire inflation pressure checks.
Make sure to check tire inflat ion pressure as part of your routine of daily vehicle checks.
■When rotating the tires
Make sure that the engine switch is off. If the tires are rotated while the engine switch is in
IGNITION ON mode, the tire position information will not be updated.
If this accidentally occurs, either turn the engine switch to off and then to IGNITION ON
mode, or initialize the system after checking th at the tire pressure is properly adjusted.
■Low profile tires
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when comp ared to standard tires. Be sure to use
snow tires or tire chains
* on snowy and/or icy roads and drive carefully at a speed appro-
priate for road and weather conditions.
*: Tire chains cannot be mounted on the 18-inch tires. Snow tires should be used instead.

4887-3. Do-it-yourself maintenance
IS350 AWD/IS350/IS300 AWD/IS300_U(OM53E34U)
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects th e radio wave signals is installed.
• If there is a lot of snow or ice on the vehi cle, particularly around the wheels or wheel
housings.
• If the tire inflation pressure is extr emely higher than the specified level.
• If tires not equipped with tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-
port or other facility that generates st rong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless
communication device
If tire position information is not correctly displayed due to the radio wave conditions,
the display may be corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could be
extended.
●When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function.
■The initialization operation
●Make sure to carry out initialization afte r adjusting the tire inflation pressure.
Also, make sure the tires are cold before carryi ng out initialization or tire inflation pres-
sure adjustment.
●If you have accidentally turned the engine swit ch off during initialization, it is not neces-
sary to press the reset switch again as initialization will restart automatically when the
engine switch has been turned to IG NITION ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary, adjust the
tire inflation pressure to the specified leve l when the tires are cold, and conduct initial-
ization again.
■When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases, the set-
tings 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 pres sure warning reset switch, the tire pressure warning light
does not blink 3 times.
●After carrying out the initializat ion procedure, the tire pressure warning light blinks for 1
minute then stays on after driving for 20 minutes.

5648-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U(OM53E34U)
■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY” on the
tire sidewall.
Use the compact spare tire tempor arily, and only in an emergency.
●Make sure to check the tire inflation pressure of the compact spare tire.
( → P. 593)
■When using the compact spare tire
As the compact spare tire is not equipped wi th a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare tire will not be indicated by the tire pressure
warning system. Also, if you replace the compact spare tire after the tire pressure warn-
ing light comes on, the light remains on.
■When the compact spare tire is equipped
The vehicle becomes lower when driving with the compact spare tire compared to when
driving with standard tires.
■If you have a flat rear tire on a road covered with snow or ice (vehicles with front and
rear tires of the same size)
Install the compact spare tire on one of the front wheels of the vehicle. Perform the fol-
lowing steps and fit tire chains to the rear tires:
Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehicle.
Fit tire chains to the rear tires.
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653Alphabetical index
IS350 AWD/IS350/IS300 AWD/IS300_U(OM53E34U)
Tachometer .................................................81
Tail lights.....................................................194
Light switch ............................................ 194
Replacing light bulbs ....................... 509
Talk switch
*............................................ 373
Telephone switches
*.......................... 373
Theft deterrent system Alarm............................................................. 71
Engine immobiliz er system..............68
Luggage security system .................123
Theft prevention labels ....................... 74
Tire inflation pressure ......................... 493 Maintenance data ............................. 593
Tire inflation pressure display function ............................................... 484
Warning light .......................................524
Tire information ..................................... 599 Glossary ................................................ 606
Size ........................................................... 602
Tire identification number............... 601
Uniform Tire Quality Grading.............................................. 604
Tire pressure warning system ......... 484 Initializing............................................... 485
Installing tire pressure warning valves and transmitters ............... 484
Registering ID codes ...................... 485
Tire pressure warning reset switch................................................... 485
Warning light .......................................524 Tires ........................................................... 483
Chains ..................................................... 298
Checking ...............................................483
If you have a flat tire ..........................556
Inflation pressure................................593
Information............................................599
Replacing ...............................................556
Rotating tires ........................................ 484
Size ...........................................................593
Snow tires .............................................. 299
Spare tire................................................556
Tire inflation pressure display function................................................ 484
Tire pressure warning system ..... 484
Warning light ....................................... 524
Tools ...........................................................557
Top tether strap ........................................64
Total load capacity................................. 175
Towing Dinghy towing ....................................... 177
Emergency towing .............................514
Towing eyelet ........................................ 517
Trailer towing......................................... 176
TRAC (Traction Control)..................292
Transmission ............................................183 Automatic transmission ................... 183
Driving mode select switch ..........288
If the shift lever cannot be shifted from P .................................... 188
M mode ................................................... 186
Paddle shift switches......................... 185
T
*: For vehicles with a naviga tion system, refer to the
“NAVIGATION SYSTEM OWNER’S MANUAL”.