tire pressure LEXUS RX450h 2021 Owner's Manual

3836-3. Do-it-yourself maintenance
6
Maintenance and care
■Situations in which the tire pressure
warning system may not operate prop-
erly
●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.
• If a window tint that affects the 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 extremely higher than the specified level.
• If wheel without the tire pressure warning
valve and transmitter is used.
• If the ID code on the tire pressure warn- ing valves and transmitters is not regis-
tered in the tire pressure warning
computer.
●Performance may be affected in the fol-
lowing situations.
• Near a TV tower, electric power plant, gas station, radio stat
ion, large display,
airport or other fac ility that generates
strong 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 pr essure declines rap-
idly for example when a tire has burst, the
warning may not function.
■Warning performance of the tire pres-
sure 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.
■Tire pressure warning system certification
Except for vehicles sold in Canada

3846-3. Do-it-yourself maintenance
For vehicles sold in Canada
When replacing tires or wheels, tire
pressure warning valves and transmit-
ters 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 warn-
ing valve and transmitter ID codes reg-
istered by your Lexus dealer.
Installing tire pressure warning
valves and transmitters

3856-3. Do-it-yourself maintenance
6
Maintenance and care
( P.387)
■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 20 min-
utes, the tire pressure warning light blinks
for 1 minute and stays on to indicate a sys-
tem malfunction.
■The tire pressure warning system
must be initialized in the following
circumstances:
 When the tire inflation pressure is
changed such as when changing
traveling speed.
 When the tire inflation pressure is
changed such as when the tire size
is changed.
 When rotating the tires.
When the tire pressure warning system
is initialized, the current tire inflation
pressure is set as the benchmark pres-
sure.
■How to initialize the tire pressure
warning system
1 Park the vehicle in a safe place and
turn the power switch off.
Initialization cannot be performed while
the vehicle is moving.
2 Adjust the tire inflation pressure to
the specified cold tire inflation pres-
sure level.
Make sure to adjust the tire pressure to the
specified cold tire infl ation pressure level.
The tire pressure warning system will oper-
ate based on this pressure level.
3 Turn the power switch to ON
mode.
4 Select on the multi-information
display.
5 Press or of the meter con-
trol switch, select the “Vehicle Set-
NOTICE
■Repairing or replacing tires, wheels,
tire pressure warning valves, trans-
mitters and tire valve caps
●When removing or fitting the wheels,
tires or the tire pressure warning
valves and transmitters, contact your
Lexus dealer as the tire pressure warn-
ing valves and transmitters may be
damaged if not handled correctly.
●Make sure to install the tire valve caps.
If the tire valve caps are not installed,
water could enter the tire pressure
warning valves and the tire pressure
warning valves could be bound.
●When replacing tire valve caps, do not
use tire valve caps other than those
specified. The cap may become stuck.
■To avoid damage to the tire pressure
warning valves and transmitters
When a tire is repaired with liquid seal-
ants, the tire pressu re warning valve and
transmitter may not operate properly. If a
liquid sealant is used , contact your Lexus
dealer or other qualified service shop as
soon as possible. Make sure to replace
the tire pressure warning valve and trans-
mitter when replacing the tire. ( P.384)
Initializing the tire pressure
warning system

3866-3. Do-it-yourself maintenance
tings” screen and then press the .
6 Press or of the meter con-
trol switch, select the “TPMS”
screen and then press and hold the
until the tire pressure warn-
ing light blinks slowly 3 times.
“- -” will be displayed for inflation pressure
of each tire on the multi-information dis-
play while the tire pr essure warning system
determines the position of each tire.
7 Drive the vehicle at approximately
25 mph (40 km/h) or more for
approximately 10 to 30 minutes
until the inflation pressure of each
tire is displayed on the multi-infor-
mation display.
When position of each tire is determined,
the inflation pressure of each tire will be
displayed on the multi-information display.
If tire inflation pr essure becomes low
before the inflation pr essure is displayed,
the tire pressure warning light will come
on.
Depending on the vehicle and driving con-
ditions, initialization may take up to
approximately 1 hour to complete.
■Initializing the tire pressure warning sys-
tem
Initialize the system with the tire inflation
pressure adjusted to the specified level.
■If you press the tire pressure warning
reset switch accidentally
If initialization is perf ormed, adjust the tire
inflation pressure to the specified level and
initialize the tire pressure warning system
again.
■Initialization procedure
●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 inflation
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 automatically
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.
●While the position of each tire is being
determined and the inflation pressures
are not being displayed on the
multi-information display, if the inflation
pressure of a tire drops, the tire pressure
warning light will come on.
■When initialization of the tire pressure
warning system has failed
Initialization may take longer to complete if
the vehicle is driven on an unpaved road.
When performing initia lization, drive on a
paved road if possible. Depending on the
driving environment and condition of the
tires, initialization will be completed in
approximately 10 to 30 minutes. If initializa-
tion is not complete after driving approxi-
mately 10 to 30 minutes, continue driving
for a while.
If the inflation pressure of each tire is not
displayed after driving for approximately 1
hour, perform the following procedure.
●Park the vehicle in a safe place for
approximately 20 minutes. Then drive
straight (with occasional left and right
turns) at approximately 25 mph (40
km/h) or more for approximately 10 to
30 minutes.

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.