2021 LEXUS IS300 Owners Manual

1774-5. Using the driving support systems
4
Driving
• When passing a detectable object in an oncoming lane that is stopped to make a
right/left turn
• When a detectable object approaches very close and then stops before entering
the path of your vehicle
• If the front of your vehicle is raised or low- ered, such as when on an uneven or
undulating road surface
• When driving on a road surrounded by a structure, such as in a tunnel or on an iron
bridge
• When there is a metal object (manhole cover, steel plate, etc.), steps, or a protru-
sion in front of your vehicle
• When passing under an object (road sign, billboard, etc.)
• When approaching an electric toll gate barrier, parking area barrier, or other
barrier that opens and closes
• When using an automatic car wash
• When driving through or under objects that may contact your vehicle, such as
thick grass, tree branches, or a banner • When driving through steam or smoke
• When driving near an object that reflects
radio waves, such as a large truck or
guardrail
• When driving near a TV tower, broad- casting station, elec tric power plant,
radar equipped vehicles, etc., or other
location where strong radio waves or
electrical noise may be present
• 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.)
• While making a right/left turn, when an
oncoming vehicle or a crossing pedes-
trian has already exited the path of your
vehicle
• While making a right/left turn, closely in front of an oncoming vehicle or a cross-
ing pedestrian.
• While making a right/left turn, when an oncoming vehicle or a crossing pedes-
trian stops before en tering the path of
your vehicle
• While making a right/left turn, when an oncoming vehicle turns right/left in front
of your vehicle
• While steering into the direction of oncoming traffic
■Situations in which the system may not
operate properly
●In some situations su ch as the following,
an object may not be detected by the

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

1794-5. Using the driving support systems
4
Driving
as heavy rain, fog, snow or a sandstorm
• When driving through steam or smoke
• When the surrounding area is dim, such as at dawn or dusk, or while at night or in
a tunnel, making a detectable object
appear to be nearly the same color as its
surroundings
• When driving in a place where the sur- rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• After the engine 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 front cam- era
• The vehicle is being driven at extremely high speeds
• When driving on a hill
• If the radar sensor or front camera is mis-
aligned
• When driving in a tr affic lane separated
by more than one lane where oncoming
vehicles are driving while making a
right/left turn
• When largely out of place with the oppo- site facing targeted oncoming vehicle
during a right/left turn • While making a right/left turn, when a
pedestrian approaches from behind or
side of your vehicle
●In addition to the above, in some situa-
tions, such as the following, the emer-
gency steering assist may not operate.
• When the white (yellow) lane lines are difficult to see, such as when they are
faint, diverging/merging, or a shadow is
cast upon them
•When the lane is wi der or narrower than
normal
• When there is a light and dark pattern on the road surface, such as due to road
repairs
• When the target is too close
• When there is insuffic ient safe or unob-
structed space for the vehicle to be
steered into
• If oncoming vehicle is present
• If VSC function is operating
●In some situations su ch as the following,
sufficient braking forc e or steering force
may not be obtained, preventing the sys-
tem 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
• When the road surface has deep wheel tracks
• When driving on a hill road
• When driving on a road that has inclines
to the left or right
■If VSC is disabled
●If VSC is disabled ( P.239), the
pre-collision brake assist and pre-colli-
sion braking functions are also disabled.

1804-5. Using the driving support systems
●The PCS warning light will turn on and
“VSC Turned OFF Pre-Collision Brake
System Unavailable” will be displayed on
the multi-information display.LTA (Lane Tracing Assist)
While driving on a road with clear
white (yellow) lane lines, the LTA
system warns the driver if the vehi-
cle may deviate from the current
lane or course
*, and also can
slightly operate the steering wheel
to help avoid deviation from the
lane or course
*. Also, while the
dynamic radar cruise control with
full-speed range ( P.192) is oper-
ating, this system will operate the
steering wheel to maintain the vehi-
cle’s lane position.
The LTA system recognizes white
(yellow) lane lines or a course
*
using the front camera. Addition-
ally, it detects preceding vehicles
using the front camera and radar.
*: Boundary between asphalt and the side of the road, such as grass, soil, or
a curb

1814-5. Using the driving support systems
4
Driving
WARNING
■Before using LTA system
●Do not rely solely upon the LTA sys-
tem. The LTA system does not auto-
matically drive the vehicle or reduce
the amount of attention that must be
paid to the area in front of the vehicle.
The driver must always assume full
responsibility for driving safely by pay-
ing careful attention to the surround-
ing conditions and operating the
steering wheel to correct the path of
the vehicle. Also, the driver must take
adequate breaks when fatigued, such
as from driving for a long period of
time.
●Failure to perform appropriate driving
operations and pay careful attention
may lead to an accident, resulting in
death or serious injury.
■Situations unsuitable for LTA system
In the following situations, use the LTA
switch to turn the system off. Failure to do
so may lead to an acc ident, resulting in
death or serious injury.
●Vehicle is driven on a road surface
which is slippery due to rainy weather,
fallen snow, freezing, etc.
●Vehicle is driven on a snow-covered
road.
●White (yellow) lines are difficult to see
due to rain, snow, fog, dust, etc.
●Vehicle is driven in a temporary lane or
restricted lane due to construction
work.
●Vehicle is driven in a construction
zone.
●A spare tire, tire chains, etc. are
equipped.
●When the tires have been excessively
worn, or when the tire inflation pres-
sure is low.
●During emergency towing.
■Preventing LTA system malfunctions
and operations performed by mistake
●Do not modify the headlights or place
stickers, etc. on the surface of the
lights.
●Do not modify the suspension etc. If
the suspension etc. needs to be
replaced, contact your Lexus dealer.
●Do not install or place anything on the
hood or grille. Also, do not install a
grille guard (bull bars, kangaroo bar,
etc.).
●If your windshield needs repairs, con-
tact your Lexus dealer.
■Conditions in which functions may
not operate properly
In the following situations, the functions
may not operate properly and the vehicle
may depart from its la ne. Drive safely by
always paying careful attention to your
surroundings and operate the steering
wheel to correct the path of the vehicle
without relying solely on the functions.
●When the follow-up cruising display is
displayed (
P.185) and the preced-
ing vehicle changes lanes. (Your vehi-
cle may follow the preceding vehicle
and also change lanes.)
●When the follow-up cruising display is
displayed (
P.185) and the preced-
ing vehicle is swaying. (Your vehicle
may sway accordingly and depart from
the lane.)
●When the follow-up cruising display is
displayed (
P.185) and the preced-
ing vehicle departs from its lane. (Your
vehicle may follow the preceding vehi-
cle and depart from the lane.)

1824-5. Using the driving support systems
WARNING
●When the follow-up cruising display is
displayed (
P.185) and the preced-
ing vehicle is being driven extremely
close to the left/right lane line. (Your
vehicle may follow the preceding vehi-
cle and depart from the lane.)
●Vehicle is being driven around a sharp
curve.
●Objects or patterns that could be mis-
taken for white (yellow) lines are pres-
ent on the side of th e road (guardrails,
reflective poles, etc.).
●Vehicle is driven where the road
diverges, merges, etc.
●Repair marks of asphalt, white (yellow)
lines, etc. are present due to road
repair.
●There are shadows on the road that
run parallel with, or cover, the white
(yellow) lines.
●The vehicle is driven in an area without
white (yellow) lines, such as in front of a
tollgate or checkpoint, or at an inter-
section, etc.
●The white (yellow) lines are cracked,
“Botts’ dots”, “Raised pavement
marker” or stones are present.
●The white (yellow) lines cannot be
seen or are difficult to see due to sand,
etc.
●The vehicle is driven on a road surface
that is wet due to rain, puddles, etc.
●The traffic lines are yellow (which may
be more difficult to recognize than
lines that are white).
●The white (yellow) lines cross over a
curb, etc.
●The vehicle is driven on a bright sur-
face, such as concrete.
●If the edge of the road is not clear or
straight.
●The vehicle is driven on a surface that
is bright due to reflected light, etc.
●The vehicle is driven in an area where
the brightness change s suddenly, such
as at the entrances and exits of tunnels,
etc.

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

1844-5. Using the driving support systems
■Steering assist function
When the system determines that the
vehicle might depart from its lane or
course
*, the system provides assis-
tance as necessary by operating the
steering wheel in small amounts for a
short period of time to keep the vehicle
in its lane.
Vehicle with BSM: When the system deter-
mines that the vehicle might depart from its
lane and that the possibility of a collision
with an overtaking vehicle in the adjacent
lane is high, the steeri ng assist function 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
■Vehicle sway warning function
When the vehicle is swaying within a
lane, the warning buzzer will sound and
a message will be displayed on the
multi-information display to alert the
driver.
■Lane centering function
This function is linked with dynamic
radar cruise control with full-speed
range and provides the required assis-
tance by operating the steering wheel
to keep the vehicle in its current lane.
When dynamic radar cruise control with
full-speed range is not operating, the lane
centering function does not operate.
In situations where the white (yellow) lane
lines are difficult to see or are not visible,
such as when in a traffic jam, this function
will operate to help follow a preceding
vehicle by monitoring the position of the
preceding vehicle.