Page 487 of 660

4877-3. Do-it-yourself maintenance
7
Maintenance and care
IS350 AWD/IS350/IS300 AWD/IS300_U
◆Initializing the tire pressure warning system
■The tire pressure warning system must be initialized in the following circum-
stances:
●When rotating the tires.
When the tire pressure warning system is initialized, the current tire inflation
pressure is set as the benchmark pressure.
■How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the engine switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to th e specified cold tire inflation pressure
level. ( P. 595)
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 switch to IGNITION ON mode.
Press and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly 3 times.
Wait for a few minutes with the engine switch in IGNITION ON mode and
then turn the engine switch off.
◆Registering ID codes
The tire pressure warning valve and tran smitter is equipped with a unique ID
code. When replacing a tire pressure warning valve and transmitter, it is nec-
essary to register the ID code. Have the ID code registered by your Lexus
dealer.
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3
4
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Page 488 of 660

4887-3. Do-it-yourself maintenance
IS350 AWD/IS350/IS300 AWD/IS300_U
■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.
Page 490 of 660

4907-3. Do-it-yourself maintenance
IS350 AWD/IS350/IS300 AWD/IS300_U
■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.
Page 500 of 660
5007-3. Do-it-yourself maintenance
IS350 AWD/IS350/IS300 AWD/IS300_U
Turn the engine switch off.
Open the glove box. Lift up the side
with the stay, disconnect the stay
tabs and remove the partition by
pulling horizontally.
Press the tabs and remove the filter
cover.
Press the tabs and remove the filter
case.
Air conditioning filter
The air conditioning filter must be ch anged regularly to maintain air condi-
tioning efficiency.
Removal method
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Page 504 of 660
5047-3. Do-it-yourself maintenance
IS350 AWD/IS350/IS300 AWD/IS300_U
Turn the engine switch off.
Open the Fuse box cover.
Checking and replacing fuses
If any of the electrical components do not operate, a fuse may have blown. If
this happens, check and repl ace the fuses as necessary.
1
2
Engine compartment (type A fuse
box)
Push the tab in and lift the lid off.Engine compartment (type B fuse
box)
Push the tab in and lift the lid off.
Driver’s side instrument panel
Remove the lid.
Page 513 of 660

513
When trouble arises8
IS350 AWD/IS350/IS300 AWD/IS300_U
8-1. Essential informationEmergency flashers ................... 514
If your vehicle has to be stopped in an
emergency.................................. 515
If the vehicle is trapped in rising water ................................. 516
8-2. Steps to take in an emergency
If your vehicle needs to be towed .............................................517
If you think something is wrong ........................................... 523
Fuel pump shut off system ...... 524
If a warning light turns on or a warning buzzer
sounds.......................................... 525
If a warning message is displayed..................................... 532
If you have a flat tire ..................559
If the engine will not start ........ 570
If the electronic key does not operate properly ............. 572
If the vehicle battery is discharged ................................. 575
If your vehicle overheats ......... 579
If the vehicle becomes stuck .............................................583
Page 514 of 660
514
IS350 AWD/IS350/IS300 AWD/IS300_U8-1. Essential information
Press the switch.
All the turn signals will flash.
To turn them off, press the switch once
again.
■Emergency flashers
If the emergency flashers are used for a long time while the engine is not operating, the
battery may discharge.
Emergency flashers
The emergency flashers are used to warn other drivers when the vehicle has
to be stopped in the road due to a breakdown, etc.
Page 515 of 660

5158-1. Essential information
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
Steadily step on the brake pedal with both feet and firmly depress it.
Do not pump the brake pedal repeatedly as this will increase the effort required to
slow the vehicle.
Shift the shift lever to N.
If the shift lever is shifted to N
After slowing down, stop the vehicle in a safe place by the road.
Stop the engine.
If the shift lever cannot be shifted to N
Keep depressing the brake pedal with both feet to reduce vehicle speed as
much as possible.
To stop the engine, press and hold
the engine switch for 2 consecutive
seconds or more, or press it briefly 3
times or more in succession.
Stop the vehicle in a safe place by the road.
If your vehicle has to be stopped in an emergency
Only in an emergency, such as if it becomes impossible to stop the vehicle in
the normal way, stop the vehicl e using the following procedure:
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2
3
4
3
Press and hold for 2 seconds or more
or press briefly 3 times or more
4
WARNING
■If the engine has to be turned off while driving
Power assist for the brakes and steering wheel will be lost, making the brake pedal
harder to depress and the steering wheel heav ier to turn. Decelerate as much as possi-
ble before turning off the engine.
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