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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
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4527-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the power switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire inflation
pressure level. (P. 570)
Make sure to adjust the tire pressure to the specified cold tire inflation pres-
sure level. The tire pressure warning system will operate based on this pres-
sure level.
Turn the power switch to 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 power switch in ON mode and then
turn the power switch off.
Registering ID codes
The tire pressure warning valve and transmitter is equipped with a
unique ID code. When replacing a tire pressure warning valve and
transmitter, it is necessary to register the ID code. Have the ID code
registered by any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.
1
2
3
4
5
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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.
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4557-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
When 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 prop-
erly. If repeated attempts to record tire inflation pressure settings are unsuccess-
ful, have the vehicle inspected by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
When operating the tire pressure warning reset switch, the tire pressure warning
light does not blink 3 times.
After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for 20 minutes.
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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.
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4627-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
Chock the tires.
Slightly loosen the wheel nuts
(one turn).
Turn the tire jack portion “A” by
hand until the notch of the jack is
in contact with the jack point.
The jack point guides are located
under the rocker panel. They indi-
cate the jack point positions.
Replacing a tire
1
TireWheel chock positions
FrontLeft-hand sideBehind the rear right-hand side tire
Right-hand sideBehind the rear left-hand side tire
RearLeft-hand sideIn front of the front right-hand side tire
Right-hand sideIn front of the front left-hand side tire
2
3
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4637-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
Raise the vehicle until the tire is
slightly raised off the ground.
Remove all the wheel nuts and
the tire.
When resting the tire on the ground,
place the tire so that the wheel
design faces up to avoid scratching
the wheel surface.
4
5
CAUTION
Replacing a tire
Observe the following precautions to reduce the risk of death or serious injury.
Have the wheel nuts tightened with a torque wrench to 103 N•m (10.5 kgf•m,
76 ft•lbf) as soon as possible after changing wheels.
Failure to follow these precautions could cause the nuts to loosen and the
wheel may fall off, which could lead to an accident causing death or serious
injury.
Do not attach a heavily damaged wheel ornament, as it may fly off the wheel
while the vehicle is moving.
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4787-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
After a fuse is replaced
If the lights do not turn on even after the fuse has been replaced, a bulb may
need replacement. (P. 479)
If the replaced fuse blows again, have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional.
If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
When replacing light bulbs
Lexus recommends that you use genuine Lexus products designed for this vehi-
cle. Because certain bulbs are connected to circuits designed to prevent overload,
non-genuine parts or parts not designed for this vehicle may be unusable.
CAUTION
To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to the vehicle, and possibly a fire or injury.
Never use a fuse of a higher amperage rating than that indicated, or use any
other object in place of a fuse.
Always use a genuine Lexus fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
Do not modify the fuses or fuse boxes.
Fuse box near the power control unit
Never check or replace the fuses as there are high voltage parts and wiring near
the fuse box.
Doing so may cause electric shock, resulting in death or serious injury.
NOTICE
Before replacing fuses
Have the cause of electrical overload determined and repaired by any autho-
rized Lexus dealer or repairer, or another duly qualified and equipped profes-
sional as soon as possible.