inflation pressure LEXUS NX300h 2020 User Guide

3556-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
6
Maintenance and care
Check if the treadwear indicators are
showing on the tires. Also check the
tires for uneven wear, such as excessive
wear on one side of the tread.
Check the spare tire condition and
pressure if not rotated. New tread
Worn tread
Treadwear indicator
The location of treadwear indicators is
shown by a “TWI” or mark, etc.,
molded into the sidewall of each tire.
Replace the tires if the treadwear indica- tors are showing on a tire.
■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 repe atedly 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.432)
■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 driving on snow-covered
or icy roads. For driving on snow-covered
Tires
Replace or rotate tires in accor-
dance with maintenance schedules
and treadwear.
Checking tires
A
B
C

3566-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_enroads 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, however, 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 using snow tires. If
you need snow tires,
select tires of the
same size, construction and load capacity
as the originally insta lled 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.277)
■If the tread on snow tires wears down
below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is
lost.
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 in terval as tire inspec-
tion.
Do not fail to initialize the tire pressure
warning system after tire rotation.
WARNING
■When inspecting or replacing tires
Observe the following precautions to
prevent accidents.
Failure to do so may cause damage to
parts of the drive train 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.
●Do not tow if your vehicle has a com-
pact spare tire installed.
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.
■If tire inflation pressure of each tire
becomes low while driving
Do not continue driving, or your tires
and/or wheels may be ruined.
Tire rotation

3576-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
6
Maintenance and care
Front
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 warning light.
( P.392)
 The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
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.
■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 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 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
●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.
Tire pressure warning system
A

3616-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
6
Maintenance and care
istered by your Lexus dealer.
(  P.362)
■When replacing the 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 adjusting the tire inflation
pressure.
 When the tire inflation pressure is
changed such as when changing
traveling speed.
 When rotating the tires.
 When changing the tire.
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.
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. 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. ( P.357,
366)
Initializing the tire pressure
warning system

3626-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
4Press or of the meter con-
trol switches and select .
5 Press or of the meter con-
trol switches, select the “Vehicle
Settings” and then press .
6 Press or of the meter con-
trol switches, select the “TPMS”
and then press and hold the .
The “Tire Pressure Re calibrating. Please
Wait Until Complete” will be displayed on
the multi-information display and the tire
pressure warning light will blink slowly 3
times.
When the message disappears, initializa-
tion is complete.
■Initializing the tire pressure warning sys-
tem
Initialize the system with the tire inflation
pressure adjusted to the specified level
■The initialization operation
●Make sure to carry ou t 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.
●If you have accidenta lly 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.
■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.
■When initialization of the tire pressure
warning system has failed
Initialization ca n be completed in a few min-
utes. However, in the following cases, the
settings have not been recorded and the
system will not operate properly. If repeated
attempts to record tire inflation pressure
settings are unsuccessf ul, have the vehicle
inspected by your Lexus dealer.
●When initializing the tire pressure warn-
ing system, the tire pr essure warning light
does not blink 3 times.
●After carrying out the initialization proce-
dure, the tire pressure warning light
blinks for 1 minute then stays on after
driving for 20 minutes.
The tire pressure warning valve and
transmitter is equipped with a unique
ID code. When replacing a tire pres-
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 pressu re 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

3636-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
6
Maintenance and care
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.428)
Tire valveTire inflation pressure
Checking the specified tire infla-
tion pressure
Inspection and adjustment pro-
cedure
A

3646-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
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 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 inflation 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.
B
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.)

3656-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
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 wa rning 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.357, 366)
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.
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.

3726-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
Type AAdjustment bolt A
Adjustment bolt B
Type BAdjustment bolt A
Adjustment bolt B
 Make sure the vehicle has a full tank
of gasoline and the area around the
headlight is not deformed.
 Park the vehicle on level ground.
 Make sure the tire inflation pressure
WARNING
●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 your Lexus
dealer as soon as possible.
Headlight aim
Vertical movement adjusting
bolts
Before checking the headlight
aim
A
B
A
B

3927-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78530_en
■Master warning light (warning buzzer)
■Tire pressure warning light
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.396
Warning lightDetails/Actions
When the light comes on:
Low tire inflation pressure such as
Natural causes ( P.394)
 Flat tire ( P.400)
 Adjust the tire inflation pressure to the specified level.
The light will turn off after a few minutes. In case the
light does not turn off even if the tire inflation pressure
is adjusted, have the syst em checked by your Lexus
dealer.
When the light comes on after blinking for 1 minute:
Malfunction in the tire pressure warning system ( P.394)
 Have the system checked by your Lexus dealer.