wheel size LEXUS IS300 2021 Owners Manual

1734-5. Using the driving support systems
4
Driving
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.76) of
the multi-information display.
The system is automa tically enabled each
time the engine switch is turned to IGNI-
TION ON mode.
If the system is disabled, the PCS warn-
ing light will turn on and a message will
be displayed on the multi-information
display.
■Changing the pre-collision warn-
ing timing
The pre-collision warning timing can
be changed on ( P.76) of the
multi-information display.
The warning timing setting is retained
when the engine switch is turned off. How-
ever, if the pre-collision system is disabled
and re-enabled, the operation timing will
return to the default setting (middle).
If the pre-collision warning timing is
changed, emergency steering assist
timing will also be changed accord-
ingly.
If late is selected, emergency steering
assist would not operate in case of an
emergency.
WARNING
●When the vehicle is raised on a lift with
the engine running 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 accident 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
●When a compact spare tire or an
emergency tire puncture repair kit is
used
●If equipment (snow plow, etc.) that may
obstruct the radar sensor or front cam-
era is temporarily installed to the vehi-
cle
Changing settings of the pre-col-
lision system

1784-5. Using the driving support systems
radar sensor and front camera, prevent-
ing the system from operating properly:
• When a detectable object is approaching
your vehicle
• When your vehicle or a detectable object
is wobbling
• If a detectable object makes an abrupt maneuver (such as sudden swerving,
acceleration or deceleration)
• When your vehicle approaches a detect- able object rapidly
• When a detectable object is not directly
in front of your vehicle
• When a detectable object is near a wall, fence, guardrail, manhole cover, vehicle,
steel plate on the road, etc.
• When a detectable object is under a
structure
•When part of a detect able object is hid-
den by an object, such as large baggage,
an umbrella, or guardrail
• When there are many things which can reflect the radio waves of the radar in the
vicinity (tunnels, truss bridges, gravel
roads, snow covered road that have
tracks, etc.)
• When there is an effect on the radio waves to the radar that is installed on
another vehicle
• When multiple dete ctable objects are
close together
• If the sun or other light is shining directly
on a detectable object
• When a detectable object is a shade of white and looks extremely bright
• When a detectable object appears to be nearly the same color or brightness as its
surroundings
• If a detectable object cuts or suddenly
emerges in front of your vehicle
• When the front of your vehicle is hit by water, snow, dust, etc.
• When a very bright light ahead, such as the sun or the headlights of oncoming traffic, shines direct
ly into the front cam-
era
• When approaching the side or front of a
vehicle ahead
• If a vehicle ahead is a motorcycle
• If a vehicle ahead is narrow, such as a per- sonal mobility vehicle
• If a preceding vehicle has a small rear end, such as an unloaded truck
• If a preceding vehicle has a low rear end, such as a low bed trailer
• If a vehicle ahead has extremely high ground clearance
• If a vehicle ahead is carrying a load which protrudes past its rear bumper
• If a vehicle ahead is irregularly shaped,
such as a tractor or side car
• If a vehicle ahead is a child sized bicycle, a bicycle that is carrying a large load, a
bicycle ridden by more than one person,
or a uniquely shaped bicycle (bicycle with
a child seat, tandem bicycle, etc.)
• If a pedestrian/or the riding height of a bicyclist ahead is shorter than approxi-
mately 3.2 ft. (1 m) or taller than approxi-
mately 6.5 ft. (2 m)
• If a pedestrian/bicyclist is wearing over- sized clothing (a rain coat, long skirt,
etc.), making their silhouette obscure
• If a pedestrian is bending forward or squatting or bicyclist is bending forward
• If a pedestrian/bicyclist is moving fast
• If a pedestrian is pushing a stroller, wheel-
chair, bicycle or other vehicle
• When driving in incl ement weather such

1834-5. Using the driving support systems
4
Driving
■Lane departure alert function
When the system determines that the
vehicle might depart from its lane or
course
*, a warning is displayed on the
multi-information display, and either a
warning buzzer will sound or the steer-
ing wheel will vibrate to alert the driver.
When the warning buzzer sounds or the
steering wheel vibrates, check the area
around your vehicle and carefully operate
the steering wheel to move the vehicle
back to the center of the lane.
Vehicle with BSM: When the system deter-
mines that the vehicle might depart from its
lane and that the po ssibility of a collision
with an overtaking vehicle in the adjacent
lane is high, the lane departure alert will
operate even if the turn signals are operat-
ing.
*: Boundary between asphalt and the side of the road, such as grass, soil, or a curb
WARNING
●Light from the headlights of an oncom-
ing vehicle, the sun, etc. enters the
camera.
●The vehicle is driven on a slope.
●The vehicle is driven on a road which
tilts left or right, or a winding road.
●The vehicle is driven on an unpaved or
rough road.
●The traffic lane is excessively narrow
or wide.
●The vehicle is extremely tilted due to
carrying heavy luggage or having
improper tire pressure.
●The distance to the preceding vehicle
is extremely short.
●The vehicle is moving up and down a
large amount due to road conditions
during driving (poor roads or road
seams).
●When driving in a tunnel or at night
with the headlights off or when a head-
light is dim due to its lens being dirty or
it being misaligned.
●The vehicle is struck by a crosswind.
●The vehicle is affected by wind from a
vehicle driven in a nearby lane.
●The vehicle has just changed lanes or
crossed an intersection.
●Tires which differ by structure, manu-
facturer, brand or tread pattern are
used.
●When tires of a size other than speci-
fied are installed.
●Snow tires, etc. are equipped.
●The vehicle is being driven at
extremely high speeds.
Functions included in LTA system

2414-5. Using the driving support systems
4
Driving
●The accelerator pedal is depressed a
large amount
WARNING
■The ABS does not operate effectively
when
●The limits of tire gripping performance
have been exceeded (such as exces-
sively worn tires on a snow covered
road).
●The vehicle hydroplanes while driving
at high speed on wet or slick roads.
■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.
■Active Cornering Assist does not
operate effectively when
●Do not overly rely on Active Corner-
ing 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 and VSC.
■Hill-start assist control does not oper-
ate effectively when
●Do not overly rely on 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/VSC is activated
The slip indicator light flashes. Always
drive carefully. Reckless 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.
■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.

2434-6. Driving tips
4
Driving
4-6.Driving tips
Use fluids that are appropriate to
the prevailing outside temperatures.
•Engine oil
• Engine coolant
•Washer fluid
Have a service technician inspect
the condition of the battery.
 Have the vehicle fitted with four
snow tires or purchase a set of tire
chains for the rear tires.
*
Ensure that all tires are the specified size
and brand, and that chains match the size
of the tires.
*: Tire chains cannot be mounted on vehi-
cles with front and rear tires of differing
sizes.
Perform the following according to the
driving conditions:
 Do not try to forcibly open a window
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 (vehicles with
front and rear tires of the same size)
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)
system.
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

2444-6. Driving tips
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
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.144)
 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.
Vehicles with front and rear tires of
the same size
Use the correct tire chain size when
mounting the tire chains.
Chain size is regulated for each tire
size.
Side chain (0.12 in. [3 mm] in diam-
eter)
Cross chain (0.16 in. [4 mm] in
diameter)
When driving the vehicle
When parking the vehicle
Selecting tire chains
A
B

3046-3. Do-it-yourself maintenance
roads, the use of snow tires is recom-
mended. 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 adequate
for driving in most winter conditions as well
as for use year-round. All season tires,
however, do not have adequate traction
performance compared with snow tires in
heavy or loose snow. Also, all season tires
fall short in acceleration and handling per-
formance compared 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 regula-
tions for possible restrictions. Snow tires
should be installed on all wheels.
(  P.243)
■Low profile tires
Generally, low profile tires will wear more
rapidly and tire grip performance will be
reduced on snowy and/or icy roads when
compared to standard ti res. Be sure to use
snow tires or tire chains* on snowy and/or
icy roads and drive carefully at a speed
appropriate for road and weather condi-
tions.
*: Vehicles with front and rear tires of dif-
fering sizes: Tire chains cannot be
mounted. Snow tires should be used
instead.
■If the tread on snow tires wears down
below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is
lost.
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.
■Low profile tires
Low profile tires may cause greater dam-
age than usual to the tire wheel when
sustaining impact from the road surface.
Therefore, pay attention to the following:

3056-3. Do-it-yourself maintenance
6
Maintenance and care
Rotate the tires in the order shown.
Vehicles with front and rear tires of
the same size
To equalize tire wear and extend tire
life, Lexus recommends that tire rota-
tion is carried out at the same interval
as tire inspection.
Do not fail to initialize the tire pressure
warning system after tire rotation.
Vehicles with front and rear tires of
differing sizes
Tires cannot be rotated.
■When rotating the tires
Make sure that the engine switch is off. If the
tires are rotated while the engine switch is in IGNITION ON mode, the tire position
information will not be updated.
If this accidentally occurs, either turn the
engine switch to off and then to IGNITION
ON mode, or initialize the system after
checking that the tire pressure is properly
adjusted.
Your vehicle is equipped with a tire
pressure warning system that uses tire
pressure warning valves and transmit-
ters to detect low ti
re inflation pressure
before serious problems arise.
 The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display.
 If the tire pressure drops below a
predetermined level, the driver is
warned by a screen display and a
warning light. ( P.341)
NOTICE
●Be sure to use proper tire inflation
pressure. If tires are under-inflated,
they may be damaged more severely.
●Avoid potholes, uneven pavement,
curbs and other road hazards. Failure
to do so may lead to severe tire and
wheel damage.
■If tire inflation pres sure of each tire
becomes low while driving
Do not continue driving, or your tires
and/or wheels may be ruined.
Tire rotation
Tire pressure warning system

3066-3. Do-it-yourself maintenance
■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 pressure after the engine
switch is turned to IGNITION ON mode.
It may also take a few minutes to display
the tire inflation pres sure after inflation
pressure has been adjusted.
●Tire inflation pressure changes with tem-
perature. The displayed 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.
• If a tire has been repl aced with a tire that
is not an OE (Original Equipment) tire.
• If a tire has been repl aced with a tire that
is not of the specified size.
• If tire chains, etc. are installed.
• 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 tires not equipped with tire pressure warning valves and tr ansmitters 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 affected in the fol-
lowing situations.
• When driving near a TV tower, electric
power plant, gas station, radio station,
large display, airport or other facility that
generates strong radio waves or electri- cal 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 driv-
ing conditions. 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 initial-
ized.

3086-3. Do-it-yourself maintenance
■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 rotating the tires.
 When the tire inflation pressure is
changed such as when changing
traveling speed or load weight.
 When changing the tire size.
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, turn
the engine switch off and wait 20
minutes or more.
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 Start the engine. ( P.134)
4 Press and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks slowly
3 times.
Then a message will be displayed on the
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 a tire valve cap is not installed, water
may enter the valve and cause it to
corrode, possibly leading to the valve
sticking or air to leak from the tire.
●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.
Initializing the tire pressure
warning system