wheel size LEXUS NX300h 2018 Owners Manual

204 4-5. Using the driving support systems
LEXUS NX300h Owners Manu-
al_USA_OM78212U WARNING●
Although this system is designed to
help avoid a collision or help reduce
the impact of the coll ision, its effective-
ness may change according to various
conditions, therefore the system may
not always be able to achieve the same
level of performance.
Read the following conditions care-
fully. Do not overly rely on this system
and always drive carefully.
• Conditions under which the system
may operate even if there is no possi-
bility of a collision: → P.207
• Conditions under which the system
may not operate properly: → P.208●
Do not attempt to test the operation of
the pre-collision system yourself, as the
system may not operate properly, pos-
sibly leading to an accident.■
Pre-collision braking●
When the pre-collision braking func-
tion is operating, a large amount of
braking force will be applied.●
If the vehicle is stopped by the opera-
tion of the pre-collision braking func-
tion, the pre-collision braking function
operation will be canceled after
approximately 2 seco nds. Depress the
brake pedal as necessary.
●
The pre-collision braking function may
not operate if certain operations are
performed by the driver. If the acceler-
ator pedal is being depressed strongly
or the steering wheel is being turned,
the system may determine that the
driver is taking evasive action and pos-
sibly prevent the pre-collision braking
function from operating.
●
In some situations, while the pre-colli-
sion braking function is operating,
operation of the function may be can-
celed if the accelerator pedal is
depressed strongly or the steering
wheel is turned and the system deter-
mines that the driver is taking evasive
action. ●
If the brake pedal is being depressed,
the system may determine that the
driver is taking evasive action and pos-
sibly delay the operat ion timing of the
pre-collision braking function. ■
When to disable the pre-collision sys-
tem
In the following situations, disable the
system, as it may not operate properly,
possibly leading to an accident resulting
in death or serious injury: ●
When the vehicle is being towed ●
When your vehicle is towing another
vehicle ●
When transporting the vehicle via
truck, boat, train or similar means of
transportation ●
When the vehicle is raised on a lift with
the hybrid system on and the tires are
allowed to rotate freely ●
When inspecting the vehicle using a
drum tester such as a chassis dyna-
mometer or speedometer tester, or
when using an on vehicle wheel bal-
ancer ●
When a strong impact is applied to the
front bumper or front grille, due to an
accident or other reasons
●
If the vehicle cannot be driven in a sta-
ble manner, such as when the vehicle
has been in an accid ent or is malfunc-
tioning
●
When the vehicle is driven in a sporty
manner or off-road
●
When the tires are not properly
inflated
●
When the tires are very worn
●
When tires of a size other than speci-
fied are installed
●
When tire chains are installed

206 4-5. Using the driving support systems
LEXUS NX300h Owners Manu-
al_USA_OM78212U 1 FarThe warning will begin to operate earlier
than with the default timing.
2 MiddleThis is the default setting.
3 NearThe warning will begin to operate later
than with the default timing.
■
Operational conditions
The pre-collision system is enabled and the
system determines that the possibility of a
frontal collision with a vehicle or pedestrian
is high.
Each function is operat ional at the following
speeds: ●
Pre-collision warning:
• Vehicle speed is be tween approximately
7 and 110 mph (10 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 7 and 50 mph
[10 and 80 km/h].)
• The relative speed between your vehicle
and the vehicle or pedestrian ahead is
approximately 7 mph (10 km/h) or more.
●
Pre-collision brake assist:
• Vehicle speed is be tween approximately
20 and 110 mph (30 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 20 and 50 mph
[30 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is
approximately 20 mph (30 km/h) or
more. ●
Pre-collision braking:
• Vehicle speed is between approximately
7 and 110 mph (10 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 7 and 50 mph
[10 and 80 km/h].)
• The relative speed between your vehicle
and the vehicle or pedestrian ahead is
approximately 7 mph (10 km/h) or more.
The system may not operate in the following
situations: ●
If a 12-volt battery terminal has been dis-
connected and reconnected and then the
vehicle has not been driven for a certain
amount of time ●
If the shift lever is in R ●
If VSC is disabled (only the pre-collision
warning function wi ll be operational)■
Pedestrian detection function
The pre-collision system detects pedestri-
ans based on the size, profile, and motion of
a detected object. However, a pedestrian
may not be detected depending on the sur-
rounding brightness and the motion, pos-
ture, and angle of the detected object,
preventing the system from operating prop-
erly. ( → P.208)
■
Cancelation of the pre-collision braking
If either of the follo wing occur while the
pre-collision braking function is operating, it
will be canceled:
●
The accelerator pedal is depressed
strongly.
●
The steering wheel is turned sharply or
abruptly.

2094-5. Using the driving support systems
LEXUS NX300h Owners Manu-
al_USA_OM78212U 4
Driving rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• When a very bright light, such as the sun
or the headlights of oncoming traffic,
shines directly in to the camera sensor
• When the surrounding area is dim, such
as at dawn or dusk, or while at night or in
a tunnel
• After the hybrid system has started the
vehicle has not been driven for a certain
amount of time
• While making a left/right turn and for a
few seconds after makin g a left/right turn
• While driving on a curve and for a few
seconds after driving on a curve
• If your vehicle is skidding
• If the front of the vehicle is raised or low-
ered
• If the wheels are misaligned
• If a wiper blade is blocking the camera
sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely
high speeds.
• When driving on a hill
• If the radar sensor or camera sensor is
misaligned●
In some situations such as the following,
sufficient braking force may not be
obtained, preventing the system from
performing properly:
• If the braking functions cannot operate to
their full extent, such as when the brake
parts are extremely cold, extremely hot,
or wet
• If the vehicle is not properly maintained
(brakes or tires are excessively worn,
improper tire inflation pressure, etc.)
• When the vehicle is being driven on a
gravel road or other slippery surface
●
Some pedestrians such as the following
may not be detected by the radar sensor
and camera sensor, preventing the sys-
tem from operating properly: • Pedestrians shorter than approximately
3.2 ft. (1 m) or taller than approximately
6.5 ft. (2 m)
• Pedestrians wearing oversized clothing
(a rain coat, long skir t, etc.), making their
silhouette obscure
• Pedestrians who are carrying large bag-
gage, holding an umbrella, etc., hiding
part of their body
• Pedestrians who are bending forward or
squatting
• Pedestrians who are pushing a stroller,
wheelchair, bicycle or other vehicle
• Groups of pedestrians which are close
together
• Pedestrians who are wearing white and
look extremely bright
• Pedestrians in the dark, such as at night
or while in a tunnel
• Pedestrians whose clothing appears to
be nearly the same color or brightness as
their surroundings
• Pedestrians near walls, fences, guardrails,
or large objects
• Pedestrians who are on a metal object
(manhole cover, steel plate, etc.) on the
road
• Pedestrians who are walking fast
• Pedestrians who are changing speed
abruptly
• Pedestrians running out from behind a
vehicle or a large object
• Pedestrians who are extremely close to
the side of the vehicle (outside rear view
mirror, etc.) ■
If the PCS warning light flashes or illumi-
nates and a warning message is dis-
played on the multi-information display
The pre-collision system may be temporar-
ily unavailable or there may be a malfunc-
tion in the system.
●
In the following situations, the warning
light will turn off, the message will disap-
pear and the system will become opera-
tional when normal operating conditions
return:
• When the radar sensor or camera sensor
or the area around either sensor is hot,
such as in the sun
• When the radar sensor or camera sensor
or the area around either sensor is cold,
such as in an extremely cold environment
• When a front sensor is dirty or covered

2534-5. Using the driving support systems
LEXUS NX300h Owners Manu-
al_USA_OM78212U 4
Driving WARNING■
Stopping distance when the ABS is
operating may exceed that of normal
conditions
The ABS is not designed to shorten the
vehicle’s stopping di stance. Always main-
tain a safe distance from the vehicle in
front of you, especially in the following
situations: ●
When driving on dirt, gravel or snow-
covered roads●
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. ■
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/Trailer
Sway Control is activated
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/Trailer Sway
Control 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/Trailer Sway Con-
trol systems off unless necessary.
Trailer Sway Control is part of the VSC
system and will not operate if VSC is
turned off or experiences a malfunction. ■
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, Trailer Sway Control
and VSC systems will not function cor-
rectly if different tire s 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.
■
Trailer Sway Control precaution
The Trailer Sway Control system is not
able to reduce trailer sway in all situa-
tions. Depending on many factors such
as the conditions of the vehicle, trailer,
road surface and driving environment,
the Trailer Sway Control system may not
be effective. Refer to your trailer owner’s
manual for information on how to tow
your trailer properly.
■
If trailer sway occurs
Observe the following precautions.
Failing to do so may cause death or seri-
ous injury.
●
Firmly grip the steering wheel. Steer
straight ahead. Do not try to control
trailer sway by turning the steering
wheel.

2574-6. Driving tips
LEXUS NX300h Owners Manu-
al_USA_OM78212U 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.
 Have the vehicle fitted with four
snow 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. *
: Tire chains cannot be mounted on the
225/60R18 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 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.
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

258 4-6. Driving tips
LEXUS NX300h Owners Manu-
al_USA_OM78212U immediately to prevent it from
freezing.
 To ensure proper operation of the
climate control system fan, remove
any snow that has accumulated on
the air inlet vents in front of the
windshield.
 Check for and remove any excess
ice or snow that may have accumu-
lated on the exterior lights, vehicle’s
roof, chassis, around the tires or on
the brakes.
 Remove any snow or mud from the
bottom of your shoes before getting
in the vehicle.
Accelerate the vehicle slowly, keep a
safe distance between you and the
vehicle ahead, and drive at a reduced
speed suitable to road conditions.
 Park the vehicle and move the shift
lever to P without setting the park-
ing brake. The parking brake may
freeze up, preventing it from being
released. If the vehicle is parked
without setting the parking brake,
make sure to block the wheels.
Failure to do so may be dangerous
because it may cause the vehicle to
move unexpectedly, possibly lead-
ing to an accident. When the parking brake is in automatic
mode, release the parking brake after shift-
ing the shift lever to P. ( → P.177)  If the vehicle is left parked with the
brakes damp in cold temperatures,
there is a possibility of the brakes
freezing.
 If the vehicle is parked without set-
ting the parking brake, confirm that
the shift lever cannot be moved out
of P *
. *
: The shift lever will be locked if it is
attempted to be shifted from P to any
other position with out depressing the
brake pedal. If the shift lever can be
shifted from P, there may be a problem
with the shift lock system. Have the vehi-
cle inspected by your Lexus dealer
immediately.
Use the correct tire chain size when
mounting the tire chains. Chain size is
regulated for each tire size. 
Vehicles with 225/65R17 tires
Side chain:When driving the vehicle
When parking the vehicle WARNING■
When parking the vehicle
When parking the vehicle without apply-
ing the parking brake, make sure to
chock the wheels. If you do not chock the
wheels, the vehicle may move unexpect-
edly, possibly result ing in an accident.
Selecting tire chains

3376-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care 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.257)■
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

340 6-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U ■
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 affected in the fol-
lowing situations.
• Near a TV tower, electric power plant,
gas station, radio stat ion, large display,
airport or other faci lity 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 pressure declines rap-
idly for example when a tire has burst, the warning may not function.
When replacing tires or wheels, tire WARNING■
Caution regarding interference with
electronic devices ●
People with implantable cardiac pace-
makers, cardiac resynchronization
therapy-pacemakers or implantable
cardioverter defibrillators should not
come within 17.7 in. (450 mm) of the
tire pressure warning system initiators.
The radio waves may affect the opera-
tion of such devices.
●
Users of any electrical medical device
other than implantable cardiac pace-
makers, cardiac resynchronization
therapy-pacemakers or implantable
cardioverter defibrillators should con-
sult the manufacturer of the device for
information about its operation under
the influence of radio waves.
Radio waves could have unexpected
effects on the operation of such medi-
cal devices.
Installing tire pressure warning
valves and transmitters

3456-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 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.338, 345)  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 acci-
dent, 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

3737-2. Steps to take in an emergency
LEXUS NX300h Owners Manu-
al_USA_OM78212U 7
When trouble arises WARNING●
Avoid abrupt maneuvering and brak-
ing. If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.■
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.