2021 LEXUS RX450h tire pressure

3876-3. Do-it-yourself maintenance
6
Maintenance and care
However, in the following situations, the tire
inflation pressure will not be recorded and
the system will not operate properly. Per-
form initialization again.
●When operating the tire pressure warn-
ing reset switch, the tire pressure warning
light does not blink 3 times.
●After performing init ialization, the tire
pressure warning light blinks for 1 minute
then stays on while driving.
If the inflation pressure of each tire is still not
displayed, have the vehicle inspected by
your Lexus dealer.
The tire pressure warning valve and
transmitter is equipped with a unique
ID code. When replacing a tire pres-
sure warning valve and transmitter, it is
necessary to register the ID code.
Have the ID code registered by your
Lexus dealer. The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
(
P.460)
Tire valve
Tire pressure gauge
WARNING
■When initializing the tire pressure
warning system
Do not initializing tire inflation pressure
without first adjusting the tire inflation
pressure to the spec ified level. Other-
wise, the tire pressure warning light may
not come on even if the tire inflation pres-
sure is low, or it may come on when the
tire inflation pressure is actually normal.
Registering ID codes
Tire inflation pressure
Checking the specified tire infla-
tion pressure
Inspection and adjustment pro-
cedure
A
B

3886-3. Do-it-yourself maintenance
1Remove the tire valve cap.
2 Press the tip of the tire pressure
gauge onto the tire valve.
3 Read the pressure using the gauge
gradations.
4 If the tire inflation pressure is not at
the recommended level, adjust the
pressure.
If you add too much air, press the
center of the valve to deflate.
5 After completing the tire inflation
pressure measurem ent and adjust-
ment, apply soapy water to the
valve and check for leakage.
6 Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure
every two weeks, or at least once a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pres-
sure
Driving with incorrect ti re inflation pressure
may result in the following:
●Reduced fuel economy
●Reduced driving comfort and poor han-
dling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, have it
checked by your Lexus dealer.
■Instructions for checking tire inflation
pressure
When checking tire inflation pressure,
observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at
least 3 hours or has not been driven for
more than 1 mile or 1.5 km, you will get an
accurate cold tire in flation pressure read- ing.
●Always use a tire pressure gauge.
It is difficult to judge if a tire is properly
inflated based only on its appearance.
●It is normal for the ti
re inflation pressure
to be higher after driving as heat is gen-
erated in the tire. Do not reduce tire infla-
tion pressure after driving.
●Never exceed the vehicle capacity
weight.
Passengers and luggage weight should
be placed so that the vehicle is balanced.
WARNING
■Proper inflation is critical to save tire
performance
Keep your tires properly inflated.
If the tires are not properly inflated, the
following conditions may occur which
could lead to an accident resulting in
death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from
overheated tires
●Air leaking from between tire and
wheel
●Wheel deformation and/or tire dam-
age
●Greater possibility of tire damage
while driving (due to road hazards,
expansion joints, sharp edges in the
road, etc.)
NOTICE
■When inspecting and adjusting tire
inflation pressure
Be sure to put the tire valve caps back on.
If a valve cap is not installed, dirt or mois-
ture may get into the valve and cause an
air leak, resulting in decreased tire infla-
tion pressure.

3896-3. Do-it-yourself maintenance
6
Maintenance and care
When replacing wheels, care should
be taken to ensure that they are equiv-
alent to those removed in load capac-
ity, diameter, rim width and inset
*.
Replacement wheels are available at
your Lexus dealer.
*: Conventionally referred to as offset.
Lexus does not recommend using the
following:
 Wheels of different sizes or types
 Used wheels
 Bent wheels that have been straight-
ened
■When replacing wheels
The wheels of your vehicle are equipped
with tire pressure warning valves and trans-
mitters that allow the tire pressure warning
system to provide advance warning in the
event of a loss in tire inflation pressure.
Whenever wheels are replaced, tire pres-
sure warning valves an d transmitters must
be installed. ( P.384) Use only Lexus wheel nuts and
wrenches designed for use with
your aluminum wheels.
 When rotating, repairing or chang-
ing your tires, check that the wheel
nuts are still tight after driving 1000
miles (1600 km).
 Be careful not to damage the alumi-
num wheels when using tire chains.
 Use only Lexus genuine balance
weights or equivalent and a plastic
or rubber hammer when balancing
your wheels.
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
handling control.
Wheel selection
WARNING
■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.
■Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air
during driving, possibly causing an acci-
dent.
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 your Lexus
dealer or other qua lified service shop.
In addition, make sure to purchase
your tire pressure warning valves and
transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels
are used on your vehicle.
Tire pressure warning valves and trans-
mitters may not work properly with
non-genuine wheels.
Aluminum wheel precautions

4227-2. Steps to take in an emergency
■Rear passengers’ seat belt reminder light*1 (warning buzzer)*2
*1: This light illuminates on the center panel.Regardless of whether or not a rear passenger is present, if the power switch is turned to
ON mode with the rear seat belts unfastened, this light will also illuminate for a certain
period of time.
*2: Rear passengers’ seat belt warning buzzer:
The rear passengers’ seat belt warning buzzer sounds to alert the rear passenger that his or
her seat belt is not fastened. If the seat belt is unfastened, the buzzer sounds intermittently
for a certain period of time, af ter the seat belt is fastened and unfastened and the vehicle
reaches a certain speed.
■Tire pressure warning light
■LTA indicator (warning buzzer)
Warning lightDetails/Actions
(RX450h)
or
(RX450hL)
Warns the rear passengers to fasten their seat belts
 Fasten the seat belt.
Warning lightDetails/Actions
Indicates the following:
Low tire pressure due to flat tire;
 Low tire pressure due to natural causes; or
 The tire pressure warning system is malfunctioning
 Immediately stop the vehicle in a safe place.
Handling method ( P.425)
Warning lightDetails/Actions
(orange)
Indicates a malfunction in th e LTA (Lane Tracing Assist)
 Follow the instructions displayed on the multi-information display.
(  P.235)

4257-2. Steps to take in an emergency
7
When trouble arises
■Brake hold operated indicator
■Master warning light
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, fr ont impact sensors,
side impact sensors (front door), side
impact sensors (rear), driver’s seat position
sensor, driver’s seat be lt buckle switch, front
passenger occupant cl assification system
(ECU and sensors), “AIR BAG ON” indica-
tor light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch,
driver’s seat belt pretensioner, front passen-
ger’s seat belt pretensioner and force lim-
iter, airbags, interconnecting wiring and
power sources. ( P.30)
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient or 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
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured:  P.432
If none of the tires are punctured:
Turn the power switch off then turn it to ON
mode. Check if the tire pressure warning
light comes on or blinks.
If the tire pressure warning light blinks for
1 minute then stays on
There may be a malfunction in the tire
pressure warning system. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
A buzzer sounds and the warning light comes on and flashes to indicate
that the master warning system has detected a malfunction.
P.428

4267-2. Steps to take in an emergency
If the tire pressure warning light comes
on
1 After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2 If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( P.385)
If the warning light does not turn off several
minutes after the initia lization has been per-
formed, have the vehicle inspected by your
Lexus dealer immediately.
■The tire pressure warning light may
come on due to natural causes
The tire pressure wa rning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with
a tire pressure warning valve and transmit-
ter. If a tire goes flat, the tire pressure warn-
ing light will not turn off even though the flat
tire has been replaced with the spare tire.
Replace the spare tire with the repaired tire
and adjust the tire inflation pressure. The
tire pressure warning lig ht will go off after a
few minutes.
■Conditions that the tire pressure warn-
ing system may not function properly
 P.383
■Customization
Some functions can be customized.
(  P.480)
WARNING
■If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during br aking, 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
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel become
extremely heavy.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using more
force than usual.
■If the tire pressure warning light
comes on
Be sure to observe the following precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●Stop your vehicle in a safe place as
soon as possible. Adjust the tire infla-
tion pressure immediately.
●If the tire pressure warning light comes
on even after tire inflation pressure
adjustment, it is prob able that you have
a flat tire. Check the tire s. If a tire is flat,
change it with the spare tire and have
the flat tire repaired by the nearest
Lexus dealer.
●Avoid abrupt maneuvering and brak-
ing.
If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.

4277-2. Steps to take in an emergency
7
When trouble arises
WARNING
■If a blowout or sudden air leakage
should occur
The tire pressure warning system may
not activate immediately.
■Maintenance of the tires
Each tire, including the spare (if pro-
vided), should be checked monthly when
cold and inflated to the inflation pressure
recommended by the vehicle manufac-
turer on the vehicle placard or tire infla-
tion pressure label (tire and load
information label). (I f your vehicle has
tires of a different size than the size indi-
cated on the vehicle placard or tire infla-
tion pressure label [tire and load
information label], yo u should determine
the proper tire infl ation pressure for
those tires.)
As an added safety feature, your vehicle
has been equipped with a tire pressure
monitoring system (TPMS-tire pressure
warning system) that illuminates a low
tire pressure telltale (tire pressure warn-
ing light) when one or more of your tires
is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale
(tire pressure warnin g light) illuminates,
you should stop and check your tires as
soon as possible, and inflate them to the
proper pressure. Driving on a signifi-
cantly under-inflated tire causes the tire
to overheat and can lead to tire failure.
Under-inflation also reduces fuel effi-
ciency and tire tread life, and may affect
the vehicle’s handling and stopping abil-
ity.
Please note that the TPMS (tire pressure
warning system) is not a substitute for
proper tire maintenance, and it is the
driver’s responsibility to maintain correct
tire pressure, even if under-inflation has
not reached the level to trigger illumina-
tion of the TPMS low tire pressure telltale
(tire pressure warning light).
Your vehicle has also been equipped with
a TPMS (tire pressure warning system)
malfunction indicator to indicate when
the system is not operating properly. The
TPMS (tire pressure warning system)
malfunction indicator is combined with
the low tire pressure telltale (tire pres-
sure warning light) . When the system
detects a malfunction, the telltale will
flash for approximately one minute and
then remain continuously illuminated.
This sequence will continue upon subse-
quent vehicle start-ups as long as the
malfunction exists. When the malfunction
indicator is illuminated, the system may
not be able to detect or signal low tire
pressure as intended.
TPMS (tire pressure warning system)
malfunctions may occur for a variety of
reasons, including the installation of
replacement or alternate tires or wheels
on the vehicle that prevent the TPMS
(tire pressure warning system) from func-
tioning properly. Always check the
TPMS (tire pressure warning system)
malfunction telltale after replacing one
or more tires or wheels on your vehicle to
ensure that the replacement or alternate
tires and wheels allow the TPMS (tire
pressure warning system) to continue to
function properly.
NOTICE
■To ensure the tire pressure warning
system operates properly
Do not install tires with different specifi-
cations or makers, as the tire pressure
warning system may not operate prop-
erly.

4357-2. Steps to take in an emergency
7
When trouble arises
When replacing tires on a vehicle with
wheel lock nuts, use the following pro-
cedures to remove and install the
wheel lock nuts. The wheel lock key is
stored in the tray inside the luggage
compartment. Always return the wheel
lock key to its original position after
use, so that it does not get lost.
■Removal
For ease of removal, the wheel lock nut
should always be the first one loos-
ened.
1 Place the wheel lock key on top of
the wheel lock nut, turning until the
wheel lock key and wheel lock nut
patterns engage.
2 Place the wheel nut wrench on the
wheel lock key, and while applying
pressure on the wheel lock key,
loosen the wheel lock nut.
■Installation
For ease of installation, the wheel lock nut should always be the last one tight-
ened.
1
By hand, install a wheel lock nut on
each wheel.
2 Place the wheel lock key on top of
the wheel lock nut, turning until the
wheel lock key and wheel lock nut
patterns engage.
3 Place the wheel nut wrench on the
wheel lock key, and while applying
pressure on the wheel lock key,
tighten the wheel lock nut to the
recommended torque.
1 Secure the deck board using the
hook. ( P.331)
2 Disengage the hook and take out
the jack.
RX450h: Remove the wheel nut wrench
and then the jack.
RX450hL: Remove the jack handle and
then the jack.
WARNING
●Do not raise the vehicle while some-
one is inside.
●When raising the vehicle, do not put an
object on or under the jack.
●Do not raise the vehicle to a height
greater than that required to replace
the tire.
●Use a jack stand if it is necessary to get
under the vehicle.
●When lowering the vehicle, make sure
that there is no-one near the vehicle. If
there are people nearby, warn them
vocally before lowering.
Wheel lock nut (if equipped)
NOTICE
Do not use an impact wrench. Using an
impact wrench may cause permanent
damage to wheel lock nut and wheel lock
key. If in doubt about wheel lock applica-
tion, contact your Lexus dealer.
Taking out the jack