inflation LEXUS UX250H 2019 User Guide

3316-2. Maintenance
6
Maintenance and care
The OBD system determines that a
problem exists somewhere in the emis-
sion control system. Your vehicle may
not pass the I/M test and may need to
be repaired. Contact your Lexus
dealer to service the vehicle.
When the 12-volt battery is discon-
nected or discharged
Readiness codes that are set during
ordinary driving are erased.
Also, depending on your driving
habits, the readiness codes may not
be completely set.
 When the fuel tank cap is loose
The malfunction indicator lamp
comes on indicating a temporary
malfunction and your vehicle may
not pass the I/M test.
Fluid leaks
• There should not be any
signs of fluid leakage
after the vehicle has
been parked.
Tires
• Is the tire inflation pres-sure correct?
• The tires should not be damaged or excessively
worn.
• Have the tires been rotated according to the
maintenance schedule?
• The wheel nuts should not be loose.
Windshield
wipers/
rear window
wiper
•The wiper blades should not show any signs of
cracking, splitting, wear,
contamination or defor-
mation.
•The wiper blades should clear the wind-
shield/rear window with-
out streaking or
skipping.
ItemsCheck pointsEmission inspection and
maintenance (I/M) pro-
grams
Some states have vehicle emission
inspection programs which include
OBD (On Board Diagnostics)
checks. The OBD system monitors
the operation of the emission con-
trol system.
If the malfunction indicator lamp
comes on
Your vehicle may not pass the
I/M test in the following situa-
tions:

3346-3. Do-it-yourself maintenance
Tire inflation
pressure
( P.361)• Tire pressure gauge
• Compressed air source
Washer fluid
( P.341)
• Water or washer fluid
containing antifreeze
(for winter use)
• Funnel (used only for adding water or washer
fluid)
WARNING
The engine compartment contains many
mechanisms and fluids that may move
suddenly, become hot, or become elec-
trically energized. To avoid death or seri-
ous injury, observe the following
precautions.
■When working on the engine com-
partment
●Make sure that “IGNITION ON” on
the multi-information display and the
“READY” indicator are both off.
●Keep hands, clothi ng and tools away
from the moving fan and engine drive
belt.
●Be careful not to touch the engine,
power control unit, radiator, exhaust
manifold, etc. right after driving as they
may be hot. Oil and other fluids may
also be hot.
●Do not leave anything that may burn
easily, such as paper and rags, in the
engine compartment.
●Do not smoke, cause sparks or expose
an open flame to fuel. Fuel fumes are
flammable.
■When working near the electric cool-
ing fans or radiator grille
Be sure the power switch is OFF.
With power switch in ON, the electric
cooling fans may automatically start to
run if the air conditioning is on and/or the
coolant temperature is high. ( P.340)
ItemsParts and tools■Safety glasses
Wear safety glasses to prevent flying or
falling material, fluid spray, etc. from get-
ting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter
removed may cause excessive engine
wear due to dirt in the air.

3466-3. Do-it-yourself maintenance
■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on
a tire.
●You have tire damage such as cuts, splits,
cracks deep enough to expose the fabric,
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 with your Lexus
dealer.
■Tire life
Any tire over 6 years old must be checked
by a qualified technician even if it has sel-
dom or never been used or damage is not
obvious.
■Maximum load of tire
Check that the maximum load of the
replacement tire is greater than 1/2 of the
Gross Axle Weight Ratings (GAWR) of
either the front axle or the rear axle, which-
ever is greater.
For the GAWR, see the Certification Label.
For the maximum load of the tire, see the
load limit at maximum cold tire inflation
pressure mentioned on the sidewall of the
tire. ( P.425)
■Tire types
●Summer tires
Summer tires are high-speed perfor-
mance tires best suited to highway driv-
ing under dry conditions. Since summer
tires do not have the same traction per-
formance as snow tires, summer tires are
inadequate for drivin g on snow-covered
or icy roads. For driving on snow-covered
roads or icy roads, the use of snow tires is
recommended. When installing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide
better traction in
snow and to be ade-
quate for driving in most winter condi-
tions as well as for use year-round. All
season tires, howeve r, do not have ade-
quate traction performance compared
with snow tires in heavy or loose snow.
Also, all season tires fall short in accelera-
tion and handling performance com-
pared with summer tires in highway
driving.
●Snow tires
For driving on snow-covered roads or icy
roads, we recommend us ing snow tires. If
you need snow tires, select tires of the
same size, construction and load capacity
as the originally installed tires. Since your
vehicle has radial tires as original equip-
ment, make sure your snow tires also
have radial construction. Do not install
studded tires without first checking local
regulations for possible restrictions.
Snow tires should be installed on all
wheels. ( P.263)
■If the tread on snow tires wears down
below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is
lost.
■Replacing tires
Your vehicle may not be equipped with the
following tools and jack for replacing a tire.
In this case, when replacing tires with tires
that are not run-flat tires, purchase tools
and jack. Tools and jack can be purchased
at your Lexus dealer.
●Wheel nut wrench
●Jack
●Jack handle

3476-3. Do-it-yourself maintenance
6
Maintenance and care
Rotate the tires in the order shown.
To equalize tire wear and extend tire life,
Lexus recommends that tire rotation is car-
ried out at the same interval as tire inspec-
tion.
Do not fail to initialize the tire pressure
warning system after tire rotation.
■When rotating the tires
Make sure that the powe r switch is OFF. If
the tires are rotated while the power switch
is in ON, the tire position information will
not be updated.
If this accidentally occurs, either turn the
power switch to OFF and then to ON, or
initialize the tire pressure warning system
after checking that the tire pressure is prop-
erly adjusted.
When run-flat tires are installed, the
vehicle can be driven for a maximum of
100 miles (160 km) at a speed below
50 mph (80 km/h) after any tire goes
flat. (However, the vehicle speed may
not increase to near 50 mph [80
km/h] depending on weather or driv-
ing conditions.)
A run-flat tire has a mark on
the sidewall.
Make sure to replace the flat tire before the
vehicle has been driven for near 100 miles
(160 km). Also, do not use a repaired tire.
WARNING
■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-b elted 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.
NOTICE
■Driving on rough roads
Take particular care when driving on
roads with loose surfaces or potholes.
These conditions may cause losses in tire
inflation pressure, reducing the cushion-
ing ability of the tires. In addition, driving
on rough roads may cause damage to
the tires themselves, as well as the vehi-
cle’s wheels and body.
Tire rotation
Run-flat tires

3486-3. Do-it-yourself maintenance
■Run-flat tires
●The run-flat tires are for only this vehicle.
Do not use the tires on other vehicles.
●Do not mix run-flat tires and normal tires.
●If non-genuine Lexus wheels are used, it
may be impossible to sufficiently demon-
strate the performance of run-flat tires.
Your vehicle is equipped with a tire
pressure warning system that uses tire
pressure warning valves and transmit-
ters to detect low tire inflation pressure
before serious problems arise.
If the tire pressure drops below a
predetermined level, the driver is
warned by a screen display and a
warning light. ( P.387, 395)
 The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display. ( P.87)
The illustration used is intended as an
example, and may differ from the image
that is actually displayed on the multi-infor-
mation display.
■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.
■Tire inflation pressure
●It may take a few minutes to display the
tire inflation pressu
re after the power
switch is turned to ON. It may also take a
few minutes to display the tire inflation
pressure after inflatio n pressure has been
adjusted.
●Tire inflation pressure changes with tem-
perature. The displaye d values may also
be different from the values measured
using a tire pressure gauge.
■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.
• 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 vehi- cle, particularly around the wheels or
wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
• If wheels without tire pressure warning
valves and transmitters are 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 af fected 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,
Tire pressure warning system

3496-3. Do-it-yourself maintenance
6
Maintenance and care
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 pressure 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.
■Certification for tire pressure warning system
For vehicles sold in the U.S.A. , Hawaii, Guam and Puerto Rico

3516-3. Do-it-yourself maintenance
6
Maintenance and care
■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 tire
size. (When there are multiple spec-
ified pressures)
 After registering the ID codes.
( P.352)
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
stop the hybrid system for 20 min-
utes or more.
Initialization cannot be performed while
the vehicle is moving.
2Adjust 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 inflation pressure level.
The tire pressure warning system will oper-
ate based on this pressure level.
3Start the hybrid system ( P.162)
4
Press or of the meter con-
trol switches and select .
5
Press or of the meter con-
trol switches and select “Vehicle
Settings”, then press “OK”.
6
Press or of the meter con-
trol switches and select “TPWS”,
then press “OK”.
7
Press or of the meter con-
trol switches and select “Set Pres-
sure”. Then press and hold “OK”
until the tire pressure warning light
starts blinking.
A message is displayed on the multi-infor-
mation display. Also, “--” is displayed for
inflation pressure of each tire on the multi-
information display while the tire pressure
warning system determines the position.
8Drive at approximately 25 mph
(40 km/h) or more for approxi-
mately 10 to 30 minutes.
When initialization is complete, the infla-
tion pressure of each tire will be displayed
on the multi-information display.
Even if the vehicle is not driven at approxi-
mately 25 mph (40 km/h) or more, initial-
NOTICE
■To avoid damage to the tire pressure
warning valves and transmitters
When a tire is repaired with liquid seal-
ants, the tire pressure 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. After use of liquid seal-
ant, make sure to re place the tire pres-
sure warning valve and transmitter when
repairing or replacing the tire.
Initializing the tire pressure
warning system

3526-3. Do-it-yourself maintenance
ization can be completed by driving for a
long time. However, if initialization does not
complete after driving for 1 hour or more,
park the vehicle in a safe place for approxi-
mately 20 minutes and then drive the vehi-
cle again.
■When initializing
●Initialization is performed while driving at
a vehicle speed of approximately 25 mph
(40 km/h) or more.
●Make sure to carry out initialization after
adjusting the tire inflation pressure. Also,
make sure the tires are cold before carry-
ing out initialization or tire inflation pres-
sure adjustment.
●The tire pressure warning system can be
initialized by yourse lf, but depending on
the driving conditions and driving envi-
ronment, initialization may take some
time to complete.
■The initialization operation
●If you have accidenta lly turned the power
switch off during initialization, it is not
necessary to manually restart the initial-
ization again, as initialization will restart
automatically the next time the power
switch is turned to ON.
●If you accidentally perform initialization
when initialization is not necessary, adjust
the tire inflation pres sure 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 pres-
sure of a tire drops, the tire pressure
warning light will come on.
■If the tire pressure warning system is not
initialized properly
●In the following situations, initialization
may take longer than usual to be com-
pleted or may not be possible. Normally,
initialization completes within approxi-
mately 30 minutes.
• Vehicle is not driven at approximately 25 mph (40 km/h) or more
• Vehicle is driven on unpaved roads
• Vehicle is driven near other vehicles and system cannot recognize tire pressure
warning valve and transmitters of your
vehicle over those of other vehicles
If initialization does no t complete after driv-
ing for 1 hour or more, park the vehicle in a
safe place for approximately 20 minutes
and then drive the vehicle again.
●If the vehicle is reversed during initializa-
tion, the data up to that point is reset, so
perform the initiali zation procedure
again from the beginning.
●In the following situations, initialization
will not be started or was not completed
properly and the system will not operate
properly. Perform the initialization proce-
dure again.
• If, when attempting to start initialization, the tire pressure warning light does not
blink 3 times.
• If, when the vehicle has been driven for about 20 minutes after performing ini-
tialization, the tire pressure warning light
blinks for approximately 1 minute and
then illuminates.
If initialization canno t be completed after
performing the above procedure, contact
your Lexus dealer.
Every tire pressure warning valve and
transmitter has a unique ID code.
When replacing a tire pressure warn-
ing valve and transmitter, it is necessary
to register the ID code.
WARNING
■When initializing the tire pressure
warning system
Do not initialize 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

3536-3. Do-it-yourself maintenance
6
Maintenance and care
When registering the ID codes, per-
form the following procedure.
1Park the vehicle in a safe place, wait
for approximately 20 minutes, and
then start the hybrid system.
( P.162)
2 Press or of the meter con-
trol switches and select .
3 Press or of the meter con-
trol switches and select “Vehicle
Settings”, then press “OK”.
4 Press or of the meter con-
trol switches an d select “TPWS”,
then press “OK”.
5 Press or of the meter con-
trol switches and select “Change
Wheel Set”. Then press and hold
“OK” until the tire pressure warning
light starts slowly blinking 3 times.
Then a message will be displayed on the
multi-information display.
When registration is being performed, the
tire pressure warning light will blink for
approximately 1 minute then illuminate and
“- -” will be displayed for the inflation pres-
sure of each tire on the multi-information
display.
6Drive at 25 mph (40 km/h) or
more for approximately 10 to 30
minutes.
Registration is complete when the tire
pressure warning light turns off and the
inflation pressure of ea ch tire is displayed
on the multi-information display.
Even if the vehicle is not driven at approxi-
mately 25 mph (40 km/h) or more, regis-
tration can be completed by driving for a
long time. However, if registration does not
complete after driving for 1 hour or more,
perform the procedure again from the
beginning.
7 Initialize the tire pressure warning
system. ( P.351)
■When registering ID codes
●ID code registration is performed while
driving at a vehicle speed of approxi-
mately 25 mph (40 km/h) or more.
●Before performing ID code registration,
make sure that no wheels with tire pres-
sure warning valve and transmitters
installed are near the vehicle.
●Make sure to initializ e the tire pressure
warning system after registering the ID
codes. If the system is initialized before
registering the ID codes, the initialized
values will be invalid.
●ID codes can be registered by yourself,
but depending on the driving conditions
and driving environment, registration
may take some time to complete.
■Canceling ID code registration
●To cancel ID code regi stration after it has
been started, turn the power switch off
before driving the vehicle.
If the vehicle is driven after ID code regis-
tration is started, to cancel registration,
perform the ID code registration start
procedure again and turn the power
switch off before driving.
●If ID code registration has been canceled,
the tire pressure warning light will blink
for approximately 1 minute when the
power switch is turned to ON and then
illuminate. The tire pressure warning sys-
tem will be operational when the tire
pressure warning light turns off.
●If the warning light does not turn off even
after several minutes have elapsed, ID

3616-3. Do-it-yourself maintenance
6
Maintenance and care
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( P.422)
Tire valve Tire pressure gauge
1 Remove 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 measurement 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
Tire inflation pressure
Checking the specified tire infla-
tion pressure
Inspection and adjustment pro-
cedure
A
B