Page 481 of 628
4677-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
CAUTION
Proper inflation is critical to save tire performance
Keep your tires properly inflated. Otherwise, the following conditions may
occur and result in an accident causing death or serious injury:
Excessive wear
Uneven wear
Poor handling
Possibility of blowouts resulting from overheated tires
Poor sealing of the tire bead
Wheel deformation and/or tire separation
A greater possibility of tire damage from road hazards
NOTICE
When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on.
Without the valve caps, dirt or moisture could get into the valve and cause air
leakage, which could result in an accident. If the caps are lost, replace them as
soon as possible.
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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
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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.
Page 524 of 628
5108-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
Tire pressure warning light
When the light comes on:
Low tire inflation pressure such as
• Natural causes (P. 511)
• Flat tire (P. 531, 545)
Adjust the tire inflation pressure to the specified level.
The light will turn off after a few minutes. In case the light
does not turn off even if the tire inflation pressure is
adjusted, have the system checked by any authorized Lexus
dealer or repairer, or another duly qualified and equipped
professional.
When the light comes on after blinking for 1 minute:
Malfunction in the tire pressure warning system
Have the system checked by any authorized Lexus dealer or
repairer, or another duly qualified and equipped profes-
sional.
Warning lightWarning light/Details/Actions
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5118-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)*
1: Parking brake engaged warning buzzer:
P. 518
*2: Open door warning buzzer:
P. 516
*3: Seat belt warning buzzer:
The seat belt warning buzzer sounds to alert the driver, front passenger and
rear passengers that his or her seat belt is not fastened. The buzzer sounds for
30 seconds after the vehicle reaches a speed of 20 km/h (12 mph). Then, if the
seat belt is still unfastened, the buzzer will sound in a different tone for 90
more seconds.
Passenger detection sensor, seat belt reminder and warning buzzer
If luggage is placed on a passenger seat, the passenger detection sensor may
cause the warning light to flash and the warning buzzer to sound even if a pas-
senger is not sitting in the seat.
If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
If the malfunction indicator lamp comes on while driving
The malfunction indicator lamp will come on if the fuel tank becomes com-
pletely empty. If the fuel tank is empty, refuel the vehicle immediately. The mal-
function indicator lamp will go off after several trips.
If the malfunction indicator lamp does not go off, contact any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional as soon as
possible.
Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insufficient of the voltage temporarily
drops, the electric power steering system warning light may come on and the
warning buzzer may sound.
When the tire pressure warning light comes on
Carry out the following procedure after the tire temperature has lowered suffi-
ciently.
Check the tire inflation pressure and adjust to the appropriate level.
If the warning light does not go out even after several minutes, check that the
tire inflation pressure is at the specified level and carry out initialization.
The warning light may come on again if the above operations are conducted
without first allowing the tire temperature to lower sufficiently.
The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natu-
ral air leaks and tire inflation pressure changes caused by temperature. In this
case, adjusting the tire inflation pressure will turn off the warning light (after a
few minutes).
Conditions that the tire pressure warning system may not function properly
P. 454
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5128-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
If the tire pressure warning light frequently comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute
when the power switch is turned to ON mode, have it checked by any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional.
Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location or
audio sound.
CAUTION
If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional. The
vehicle will become extremely unstable during braking, and the ABS system
may fail, which could cause an accident resulting in death or serious injury.
When the electric power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, hold firmly
and operate using more force than usual.
If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause a
loss of vehicle control and result in death or serious injury.
Vehicles with an emergency tire puncture repair kit
Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation
pressure immediately.
If the tire pressure warning light comes on even after tire inflation pressure
adjustment, it is probable that you have a flat tire. Check the tires. If a tire is
flat, repair the flat tire by using emergency tire puncture repair kit.
Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
Vehicles with run-flat tires
Decelerate to the lowest appropriate speed as soon as possible. Do not drive
over 60 km/h (37 mph).
Check and adjust the tire inflation pressure immediately.
If the tire pressure warning light comes on even after tire inflation pressure
adjustment, it is probable that you have a flat tire. Have the tire replaced by
the nearest authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
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5138-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
NOTICE
Precaution when installing a different tire
When differently constructed tires or tires of different makers, models or tread
patterns are installed, the tire pressure warning system may not operate prop-
erly.
Page 546 of 628
5328-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
Emergency tire puncture repair kit components
Hose
Air release cap
Air pressure gaugeCompressor switch
Power plug
Stickers1
2
3
4
5
6