flat tire LEXUS UX250H 2019 User Guide

2604-5. Using the driving support systems
WARNING
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes
or uneven surfaces
■TRAC/VSC may not operate effec-
tively when
Directional control and power may not
be achievable while driving on slippery
road surfaces, even if the TRAC/VSC
system is operating.
Drive the vehicle carefully in conditions
where stability and power may be lost.
■Active Cornering Assist does not
operate effectively when
●Do not rely solely upon Active Cor-
nering Assist. Active Cornering Assist
may not operate effectively when
accelerating down slopes or driving on
slippery road surfaces.
●When Active Cornering Assist fre-
quently operates, Active Cornering
Assist may temporarily stop operating
to ensure proper operation of the
brakes, TRAC, VSC.
■Hill-start assist control does not oper-
ate effectively when
●Do not overly rely on the hill-start
assist control. Hill-start assist control
may not operate effectively on steep
inclines and roads covered with ice.
●Unlike the parking brake, hill-start
assist control is not intended to hold
the vehicle stationary for an extended
period of time. Do not attempt to use
hill-start assist control to hold the vehi-
cle on an incline, as doing so may lead
to an accident.
■When the TRAC/ABS/VSC is acti-
vated
The slip indicator light flashes. Always
drive carefully. Re ckless driving may
cause an accident. Exercise particular
care when the indicator light flashes.
■When the TRAC/VSC systems are
turned off
Be especially careful and drive at a speed
appropriate to the road conditions. As
these are the systems to help ensure
vehicle stability and driving force, do not
turn the TRAC/VSC systems off unless
necessary.
■Secondary Collision Brake
Do not overly rely on the Secondary Col-
lision Brake. This system is designed to
help reduce the possibility of further
damage due to a secondary collision,
however, that effect changes according
to various conditions. Overly relying on
the system may result in death or serious
injury.
■Replacing tires
Make sure that all ti res are of the speci-
fied size, brand, tread pattern and total
load capacity. In addition, make sure that
the tires are inflated to the recom-
mended tire inflation pressure level.
The ABS, TRAC and VSC systems will
not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further
information when replacing tires or
wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or
modifying the suspensi on will affect the
driving assist systems, and may cause a
system to malfunction.

2624-6. Driving tips
Control and maintain the vehicle at a
constant speed. Before stopping at a
toll booth or similar, allow plenty of
time to release the accelerator and
gently apply the brakes. A greater
amount of electrical energy can be
regenerated when slowing down.
Use the air conditioning only when
necessary. Doing so can help reduce
excessive gasoline consumption.
In summer: When the ambient tem-
perature is high, use the recirculated
air mode. Doing so will help to reduce
the burden on the air conditioning sys-
tem and reduce fuel consumption as
well.
In winter: Because the gasoline engine
will not automatically cut out until it and
the interior of the vehicle are warm, it
will consume fuel. Also, fuel consump-
tion can be improved by avoiding over-
use of the heater.
Make sure to check the tire inflation
pressure frequently. Improper tire infla-
tion pressure can cause poor fuel
economy.
Also, as snow tires can cause large
amounts of friction, their use on dry
roads can lead to poor fuel economy.
Use tires that are appropriate for the
season. Carrying heavy luggage will lead to
poor fuel economy. Avoid carrying
unnecessary luggage.
Installing a large
roof rack will also cause poor fuel
economy.
Since the gasoline engine starts up and
cuts out automatically when cold,
warming up the engine is unnecessary.
Moreover, frequently driving short dis-
tances will cause the engine to repeat-
edly warm up, which can lead to excess
fuel consumption.
Highway driving
Air conditioning
Checking tire inflation pressure
Luggage
Warming up before driving

2634-6. Driving tips
4
Driving
Use fluids that are appropriate to
the prevailing outside temperatures.
• Engine oil
• Engine/power control unit coolant
• Washer fluid
Have a service technician inspect
the condition of the 12-volt battery.
 It is recommended that the vehicle is
fitted with four snow run-flat tires or
purchase a set of tire chains for the
front tires.
Ensure that all tires are the same size and
brand, and that chains match the size of the
tires.
Perform the following according to the
driving conditions:
Do not try to forcibly open a window
or move a wiper that is frozen. Pour
warm water over the frozen area to
melt the ice. Wipe away the water
immediately to prevent it from
Winter driving tips
Carry out the necessary prepara-
tions and inspections before driving
the vehicle in winter. Always drive
the vehicle in a manner appropriate
to the prevailing weather condi-
tions.
Preparation for winter
WARNING
■Driving with snow tires
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in a loss of
vehicle control and cause death or seri-
ous injury.
●Use tires of the specified size.
●Maintain the recommended level of air
pressure.
●Do not drive in excess of 75 mph (120
km/h), regardless of the type of snow
tires being used.
●Use snow tires on all, not just some
wheels.
■Driving with tire chains
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in the vehicle
being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed
limit specified for the tire chains being
used, or 30 mph (50 km/h), which-
ever is lower.
●Avoid driving on bumpy road surfaces
or over potholes.
●Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking.
●Slow down sufficiently before entering
a curve to ensure that vehicle control is
maintained.
●Do not use LTA (Lane Tracing Assist).
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow
tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attach-
ment of snow tires affects the operation
of the tire pressure warning valves and
transmitters.
Before driving the vehicle

321
6
6
Maintenance and care
Maintenance and care
6-1. Maintenance and careCleaning and protecting the vehi-cle exterior ................................ 322
Cleaning and protecting the vehi- cle interior ................................. 325
6-2. Maintenance Maintenance requirements .. 328
General maintenance ............. 329
Emission inspection and mainte- nance (I/M) programs .......... 331
6-3. Do-it-yourself maintenance Do-it-yourself service precautions........................................................ 333
Hood............................................... 335
Positioning a floor jack............ 336
Engine compartment............... 337
12-volt battery............................. 342
Tires ................................................ 345
Replacing the tire ...................... 355
Tire inflation pressure ............... 361
Wheels........................................... 363
Air conditioning filter...............364
Cleaning the hybrid battery (trac- tion battery) air intake vent and
filter .............................................. 365
Electronic key battery ............. 368
Checking and replacing fuses ........................................................ 370
Headlight aim.............................. 372
Light bulbs .................................... 374

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