2019 LEXUS LS500 Owners Manual

2254-5. Using the driving support systems
LS500_OM_(U)_1810 4
Driving ■
If the PCS warning light illuminates and
a message is displayed on the
multi-information display
The system may be temporarily unavailable
or may be malfunctioning.
LTA (Lane Tracing Assist) When driving on highways and
freeways with white (yellow) lane
lines, this function alerts the driver
when the vehicle might depart from
its lane or course *
and provides
assistance by operating the steer-
ing wheel to keep the vehicle in its
lane or course *
. Furthermore, the
system provides steering assistance
when dynamic radar cruise control
with full-speed range is operating
to keep the vehicle in its lane and
when changing lanes (vehicles with
Lexus Safety System + A).
The LTA system recognizes white
(yellow) lane lines or a course *

using the front camera. Addition-
ally, it detects preceding and sur-
rounding vehicles (vehicles with
Lexus Safety System + A) using the
front camera and radar. *
: Boundary between asphalt and the
side of the road, such as grass, soil, or
a curb

226 4-5. Using the driving support systems
LS500_OM_(U)_1810 WARNING■
Before using LTA system
Do not rely solely upon the LTA system.
The LTA system does not automatically
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 driv-
ing safely by paying careful attention to
the surrounding conditions and operat-
ing 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.
●
When tires of a size other than speci-
fied are installed. ●
Vehicle is driven in traffic lanes other
than that highways and freeways. ●
During emergency towing. ■
Situations in whic h the lane change
assist function should not be used ●
When driving on a one lane road or
road without lane markers ●
When there is no broken white line
between your vehicle and the lane
toward which the turn signal is oper-
ated ■
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.

2274-5. Using the driving support systems
LS500_OM_(U)_1810 4
Driving WARNING●
When the follow-up cruising display is
displayed (  P.231) and the preceding
vehicle changes lanes. (Your vehicle
may follow the preceding vehicle and
also change lanes.)
●
When the follow-up cruising display is
displayed (  P.231) and the preceding
vehicle is swaying. (Your vehicle may
sway accordingly and depart from the
lane.)●
When the follow-up cruising display is
displayed (  P.231) and the preceding
vehicle departs from its lane. (Your
vehicle may follow the preceding vehi-
cle and depart from the lane.)●
When the follow-up cruising display is
displayed (  P.231) and the preceding
vehicle is being driven extremely close
to the left/right lane line. (Your vehicle
may follow the preceding vehicle 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,
curbs, reflective poles, etc.). ●
Vehicle is driven where the road
diverges, merges, etc.
●
Repair marks of asphalt, white (yellow)
line marks, 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 checkpoi nt, 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.

228 4-5. Using the driving support systems
LS500_OM_(U)_1810 ■
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.
When the system determines 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 lane departure alert will
operate even if the turn signals are
operating. *
: Boundary between asphalt and the side
of the road, such as grass, soil, or a curbWARNING●
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 changes suddenly, such
as at the entrances and exits of tunnels,
etc.●
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
through operation of the steering
wheel by the driver or crossed an
intersection. ●
Tires which differ by structure, manu-
facturer, brand or tread pattern are
used. ●
Snow tires, etc. are equipped. ●
The vehicle is being driven at
extremely high speeds.
Functions included in LTA system

2294-5. Using the driving support systems
LS500_OM_(U)_1810 4
Driving ■
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. If the system detect s that the steering
wheel has not been operated for a fixed
amount of time or the steering wheel is not
being firmly gripped, the steering assist
function may be canceled temporarily, a
warning message may be displayed on the
multi-information display and a warning
buzzer may sound. If the steering assist
function is canceled, release the steering
wheel and then grip it again to enable the
function.
When the system determines that the vehi-
cle might depart from its lane and that the
possibility of a collision with an overtaking
vehicle in the adjacent lane is high, the
steering assist function will operate even if the turn signals are operating. *
: 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.

230 4-5. Using the driving support systems
LS500_OM_(U)_1810 ■
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.
If the system detect s that the steering
wheel has not been operated for a fixed
amount of time or the steering wheel is not
being firmly gripped, a warning is displayed
on the multi-information display and the
warning buzzer sounds. Make sure to grip
the steering wheel firmly. ■
Lane change assist function (vehi-
cles with Lexus Safety System + A)
This function is linked to the dynamic
radar cruise control with full-speed
range and provides assistance for per-
forming lane changes by operating the
steering wheel when you hold the turn
signal lever partway (lane change posi-
tion).(  P.173)
When lane change assist function is
operating, the acceleration and decel-
eration of the vehicle is controlled
while the preceding vehicle and vehi-
cles driven in the lane toward which the
turn signal is oper ated are monitored.When the lane center ing function is not
operating, the lane change assist function
will not operate.
The lane change assist function should not
be operated when ch anging lanes on a
road that is diverging or merging.

2314-5. Using the driving support systems
LS500_OM_(U)_1810 4
Driving
Press the LTA switch to turn the LTA
system on. The LTA indicator illuminates and a mes-
sage is displayed on the multi-information
display.
Press the LTA switch again to turn the LTA
system off.
When the LTA system is turned on or off,
operation of the LTA system continues in
the same condition the next time the
engine is started. ■
Lane change assist function (vehi-
cles with Lexus Safety System + A)
Hold the turn signal lever partway
(lane change position) for approxi-
mately 1 second.(  P.173)
The direction you are signaling will be dis-
played on the multi-information display.
LTA indicator The illumination condition of the indicator
informs the driver of the system operation
status.Turning LTA system on
Indications on multi-information
display
A

232 4-5. Using the driving support systems
LS500_OM_(U)_1810 Illuminated in white: LTA system is operat-
ing.
Illuminated in green: Steering wheel assis-
tance of the steering assi st function or lane
centering function is operating.
Flashing in orange: Lane departure alert
function is operating.
Operation display of steering
wheel operation supportDisplayed when the mu lti-information dis-
play is switched to the driving assist system
information screen.
Indicates that steering wheel assistance of
the steering assist func tion or lane center-
ing function is operating.
Both outer sides of the lane are displayed:
Indicates that steering wheel assist of the
lane centering function is operating.
One outer side of the lane is displayed:
Indicates that steering wheel assist of the
steering assist function is operating.
Both outer sides of the lane are flashing:
Alerts the driver that their input is neces-
sary to stay in the center of the lane (lane
centering function).
Lane departure alert function dis-
playDisplayed when the mu lti-information dis-
play is switched to the driving assist system
information screen. 
Inside of displayed white lines is
white Indicates that the system is recognizing
white (yellow) lines or a course *
. When the
vehicle departs from it s lane, the white line
displayed on the side the vehicle departs
from flashes orange. 
Inside of displayed white lines is
black
Indicates that the system is not able to rec-
ognize white (yellow) lines or a course *
or
is temporarily canceled. *
: Boundary between asphalt and the side
of the road, such as grass, soil, or a curb
Follow-up cruising display Displayed when the multi-information dis-
play is switched to th e driving assist system
information screen.
Indicates that steering assist of the lane
centering function is operating by monitor-
ing the position of a preceding vehicle.
When the follow-up cruising display is dis-
played, if the preceding vehicle moves,
your vehicle may move in the same way.
Always pay careful attention to your sur-
roundings and operate the steering wheel
as necessary to correct the path of the
vehicle and ensure safety.
■
Lane change assist function (vehi-
cles with Lexus Safety System + A)
 Lane change assist displayB
C D