
4517-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
Your vehicle is equipped with a tire pressure warning system that uses tire
pressure warning valves and transmitters to detect low tire inflation pres-
sure before serious problems arise.
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. (P. 509)
Installing tire 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 ID codes must be registered in the tire pressure warning computer
and the tire pressure warning system must be initialized. Have tire
pressure warning valve and transmitter ID codes registered by any
authorized Lexus dealer or repairer, or another duly qualified and
equipped professional. (P. 452)
Initializing the tire pressure warning system
The tire pressure warning system must be initialized in the following
circumstances:
When rotating the tires.
When the tire inflation pressure is changed such as when changing
traveling speed or load weight.
When changing the tire size.
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the benchmark pressure.
Tire pressure warning system

4537-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
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 fab-
ric, and bulges indicating internal damage
A tire goes flat repeatedly or cannot be properly repaired due to the size or loca-
tion of a cut or other damage
If you are not sure, consult any authorized Lexus dealer or repairer, or another
duly qualified and equipped professional.
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 driving for about
10 minutes, the tire pressure warning light blinks for 1 minute and stays on to
indicate a system malfunction.
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 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.
Low profile tires (except 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 the 18-inch tires. Snow tires should be used
instead.
If the tread on snow tires wears down below 4 mm (0.16 in.)
The effectiveness of the tires as snow tires is lost.

4547-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
Situations in which the tire pressure warning system may not operate properly
In the following cases, the tire pressure warning system may not operate prop-
erly.
• 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.
• Lock nuts are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels
or wheel housings.
• If the tire inflation pressure is extremely 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 reg-
istered 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 dis-
play, airport or other facility that generates strong radio waves or electrical
noise
• When carrying a portable radio, cellular phone, cordless phone or other
wireless communication device
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 after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire infla-
tion pressure adjustment.
If you have accidentally turned the power switch off during initialization, it is
not necessary to press the reset switch again as initialization will restart auto-
matically when the power switch has been turned to 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 level when the tires are cold,
and conduct initialization again.
Warning performance of the tire pressure warning system
The warning of the tire pressure warning system will change in accordance with
the conditions under which it was initialized. For this reason, the system may
give a warning even if the tire pressure does not reach a low enough level, or if
the pressure is higher than the pressure that was adjusted to when the system was
initialized.

4587-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
CAUTION
When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drivetrain as well as danger-
ous handling characteristics, which may lead to an accident resulting in death
or serious injury.
Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
Do not use tire sizes other than those recommended by Lexus.
Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
Do not mix summer, all season and snow tires.
Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
Vehicles with an emergency tire puncture repair kit: Do not tow anything if a
tire that has been repaired using the emergency tire puncture repair kit is
installed. The load on the tire may cause unexpected damage to the tire.
When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting the
tire inflation pressure to the specified level. Otherwise, the tire pressure warn-
ing 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.

4687-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
When replacing wheels, care should be taken to ensure that they are
equivalent to those removed in load capacity, diameter, rim width and
inset
*.
Replacement wheels are available at any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
*: Conventionally referred to as “off-
set”.
Lexus does not recommend using the following:
Wheels of different sizes or types
Used wheels
Bent wheels that have been straightened
Use only Lexus wheel nuts and wrenches designed for use with your
aluminum wheels.
When rotating, repairing or changing your tires, check that the wheel
nuts are still tight after driving 1600 km (1000 miles).
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.
When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning valves and
transmitters that allow the tire pressure warning system to provide advance warn-
ing in the event of a loss in tire inflation pressure. Whenever wheels are replaced,
tire pressure warning valves and transmitters must be installed. (P. 451)
Wheels
If a wheel is bent, cracked or heavily corroded, it should be replaced.
Otherwise, the tire may separate from the wheel or cause a loss of han-
dling control.
Wheel selection
Aluminum wheel precautions

4697-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
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 a 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 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 any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional or
other qualified service shop. In addition, make sure to purchase your tire pres-
sure warning valves and transmitters at any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Ensure that only genuine Lexus wheels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly with
non-genuine wheels.

5418-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
In the following cases, the tire cannot be repaired with the emergency tire punc-
ture repair kit. Contact any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.
When the tire is damaged due to driving without sufficient air pressure
When the tire lost air pressure due to a crack or damage in the tire sidewall
When the tire is visibly separated from the wheel
When the cut or damage to the tread is 4 mm (0.16 in.) long or more
When the wheel is damaged
When two or more tires have been punctured
When there is more than one hole or cut in the damaged tire
Emergency tire puncture repair kit
The sealant has a limited lifespan. The expiry date is marked on the bottle. The
sealant should be replaced before the expiry date. Contact any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional for
replacement.
The sealant stored in the emergency tire puncture repair kit can be used only
once to temporarily repair a single tire. If the sealant in the bottle and other
parts of the kit have been used and need to be purchased, contact any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional.
The sealant can be used when the outside temperature is from -30C (-22F) to
60C (140F).
The kit is exclusively designed for size and type of tires originally installed on
your vehicle. Do not use it for tires that a different size than the original ones, or
for any other purposes.
If the sealant gets on your clothes, it may stain.
If the sealant adheres to a wheel or the surface of the vehicle body, the stain
may not be removable if it is not cleaned at once. Immediately wipe away the
sealant with a wet cloth.
During operation of the kit, a loud operation noise is produced. This does not
indicate a malfunction.
The valve of a tire that has been repaired
After a tire is repaired with the emergency tire puncture repair kit, the valve
should be replaced.
Note for checking the emergency tire puncture repair kit
Check the sealant expiry date occasionally.
The expiry date is shown on the bottle. Do not use sealant whose expiry date has
already passed. Otherwise, repairs conducted using the emergency tire puncture
repair kit may not be performed properly.

5428-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
If the tire is inflated to more than the recommended level
Disconnect the hose from the valve.
Disconnect the hose from the valve, remove the air release cap from the hose
and then reconnect the hose.
Turn the compressor switch on and wait for several seconds, then turn it off.
Check that the air pressure indicator shows the recommended level. (P. 570)
If the air pressure is lower than the recommended level, turn the compressor
switch on again and repeat the inflation procedure until the recommended pres-
sure is reached. Install the air release cap to the end of the
hose and push the protrusion on the air
release cap into the valve to let some air
out.
CAUTION
Caution while driving
Observe the following precautions.
Failure to do so may cause an accident.
The emergency tire puncture repair kit is made exclusively for your vehicle.
Do not use it on other vehicles.
Do not use the emergency tire puncture repair kit for tires that are a different
size than the specified ones or for any other purpose. Doing so may cause the
tires to not be repaired properly.
Precautions for use of the sealant
Ingesting the sealant is hazardous to your health. If you ingest sealant, con-
sume as much water as possible, then immediately consult a doctor.
If sealant gets in eyes or adheres to skin, immediately wash it off with water.
If discomfort persists, consult a doctor.
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