2021 Lexus IS350 light

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

1754-5. Using the driving support systems
4
Driving
If either of the following 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.
●Emergency steering assist
When the turn signal lights are flashing, emergency steering assist will not operate in case of
an emergency.
If any of the following occur while the emergency st eering assist function is operating, it will
be canceled:
• The accelerator pedal is depressed strongly.
• The steering wheel is turned sharply or abruptly.
• The brake pedal is depressed.
●Intersection right/left turn a ssistance (pre-collision warning)
When the turn signal lights are not flashing, suppor t for turning left or right at an intersection
which targets oncoming vehicles does not work.
●Intersection right/left turn a ssistance (pre-collision braking)
Detectable objectsVehicle speedRelative speed between your
vehicle and object
Preceding and stopped vehi- clesApprox. 7 to 110 mph (10 to 180 km/h)Approx. 7 to 110 mph (10 to 180 km/h)
Oncoming vehiclesApprox. 7 to 110 mph (10 to 180 km/h)Approx. 13 to 110 mph (20 to 180 km/h)
Bicyclists and pedestriansApprox. 7 to 50 mph (10 to 80 km/h)Approx. 7 to 50 mph (10 to 80 km/h)
Detectable objectsVehicle speedRelative speed between your vehicle and object
Preceding and stopped vehi-cles, bicyclists and pedestri- ansApprox. 25 to 50 mph (40 to 80 km/h)Approx. 25 to 50 mph (40 to 80 km/h)
Detectable objectsVehicle speedOncoming vehicle speedRelative speed
between your vehi- cle and object
Oncoming vehiclesApprox. 7 to 15 mph (10 to 25 km/h)Approx. 20 to 35
mph (30 to 55 km/h)Approx. 25 to 50 mph (40 to 80 km/h)
PedestriansApprox. 7 to 15 mph (10 to 25 km/h)Approx. 7 to 15 mph (10 to 25 km/h)

1764-5. Using the driving support systems
When the turn signal lights are not flashing, support for turning left or right at an intersection
which targets oncoming vehicles does not work.
■Object detection function
The system detects ob jects based on their
size, profile, motion, etc. However, an object
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.177)
The illustration shows an image of detect-
able objects.
■Conditions under which the system may
operate even if there is no possibility of a
collision
●In some situations such as the following,
the system may determine that there is a
possibility of a frontal collision and oper-
ate.
• When passing a detectable object, etc.
• When changing lane s while overtaking a
detectable object, etc.
• When approaching a detectable object
in an adjacent lane or on the roadside,
such as when changing the course of
travel or driving on a winding road • When rapidly closing on a detectable
object, etc.
• When approaching objects on the road-
side, such as detectable objects, guard-
rails, utility poles, trees, or walls
•When there is a dete ctable object or
other object by the roadside at the
entrance of a curve
• When there are patterns or paint in front of your vehicle that may be mistaken for a
detectable object
• When the front of your vehicle is hit by water, snow, dust, etc.
• When overtaking a de tectable object
that is changing lanes or making a
right/left turn
Detectable objectsVehicle speedOncoming vehicle
speedRelative speed
between your vehi- cle and object
Oncoming vehiclesApprox. 10 to 15 mph (15 to 25 km/h)Approx. 20 to 28
mph (30 to 45 km/h)Approx. 28 to 43
mph (45 to 70 km/h)
PedestriansApprox. 7 to 15 mph (10 to 25 km/h)Approx. 7 to 15 mph (10 to 25 km/h)

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.