
2174-5. Using the driving support systems
LS500_OM_OM50F54U_(U) 4
Driving • 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 tall er 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 co lor 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
with snow, etc.
• When the part of the windshield in front
of the camera sensor is fogged up or cov-
ered with condensation or ice (Defog-
ging the windshield: → P.314)
• If the camera sensor is obstructed, such
as when the hood is open or a sticker is
attached to the windshield near the cam-
era sensor ●
If the PCS warning light continues to flash
or remains illuminated or the warning
message does not disappear even
though the vehicle has returned to nor-
mal, the system may be malfunctioning.
Have the vehicle inspected by your Lexus
dealer immediately.
■
If VSC is disabled
●
If VSC is disabled ( → P.294), the pre-col-
lision brake assist and pre-collision brak-
ing functions are also disabled.
●
The PCS warning light will turn on and
“VSC Turned Off Pre-Collision Brake
System Unavailable” will be displayed on
the multi-information display.

2194-5. Using the driving support systems
LS500_OM_OM50F54U_(U) 4
Driving ●
Setting for “PCS” and “CAUTION” in
( → P.76) of the multi-information dis-
play.●
A shift position other than P or R is
selected. ●
Your vehicle is approaching an intersec-
tion at approximately 9 mph (15 km/h) or
lower.●
A vehicle is approaching from the left or
right in front of your vehicle at a speed
between approximately 6 mph (10 km/h)
and 37 mph (60 km/h).●
There are no preceding vehicles ahead of
your vehicle.●
The accelerator pedal is not strongly
depressed.●
The brake pedal is not being strongly
depressed.■
Situations in which the system may
operate even though no vehicles are
approaching
In certain situations, such as the following,
the system may operate even though no
vehicles are approaching: ●
When approaching objects on the road-
side, such as guardrails, traffic signs, util-
ity poles, street lig hts, trees, or walls●
When driving near a TV tower, broad-
casting station, electric power plant, or
other location where strong radio waves
or electrical noise may be present●
When passing an object on the side of the
road, such as a parked vehicle●
When a vehicle or pedestrian is
approaching from the le ft or right in front
of your vehicle from far away
●
When a vehicle or pedestrian is moving
within a parking spot, et c. next to the lane
your vehicle is driving in
●
When a pedestrian or bicyclist is moving
on a sidewalk
●
When a vehicle or pedestrian is moving
away from your vehicle
●
When a vehicle approaching from the left
or right in front of your vehicle is deceler-
ating or stops
●
When a vehicle approaching from the left or right in front of your vehicle makes a
left/right turn immediat ely in front of your
vehicle ●
When a pedestrian is approaching your
vehicle ●
When an oncoming vehicle makes a
left/right turn ●
When your vehicle enters an intersection
before a vehicle approaching from the
left or right in front of your vehicle ●
When stopped at traffic light and a vehi-
cle approaches from the left or right in
front of your vehicle ●
When driving in a location where there
are objects which reflect radar, such as
vehicles, guardrails, walls, traffic signs,
etc. ●
When making a left/right turn in front of
an approaching vehicle
●
When passing an oncoming vehicle ●
When being overtaken by another vehi-
cle ●
When driving next to another vehicle or a
pedestrian ●
When a vehicle or pedestrian
approaches the side of your vehicle
Some objects, such as the following, may be
detected and cause the FCTA system to
operate:
●
Pedestrians
■
Situations in which the system may not
operate properly
In some situations, such as the following, a
vehicle may not be detected by a front side
radar sensor, preventing the system from
operating properly:
●
If the front end or side of an approaching
vehicle is small (sports cars, etc.)

220 4-5. Using the driving support systems
LS500_OM_OM50F54U_(U) ●
If the front end of an approaching vehicle
is low (low-slung sports cars, etc.)●
If the ground clearance of an approach-
ing vehicle is extremely high●
If the shape of an approaching vehicle is
unusual (tractors, motorcycles with side-
cars, etc.)●
If a vehicle suddenly enters the detection
area on the left or ri ght in front of your
vehicle from a parking lot, etc.
●
If an approaching vehicle moves sud-
denly (sudden steering, acceleration,
deceleration, etc.)●
When driving in incl ement weather such
as heavy rain, fog, snow or a sandstorm●
After the engine has been started and the
vehicle has not been driven for a certain
amount of time●
When driving on a road with a grade that
changes sharply (sharp incline/decline)●
When driving around a sharp curve or on
an undulating road●
If a vehicle is approaching from the left or
right of the front of your vehicle diago-
nally●
When a vehicle is approaching from the
left or right in front of your vehicle from
far away
●
When there is an object between your
vehicle and an approaching vehicle
●
When driving in a lo cation where there
are objects which reflect radar, such as
guardrails, walls, vehicles, etc.
●
When a group of vehicles which are close
together approach
●
Immediately after the FCTA system has
been enabled ■
When the PCS warning light is flashing
and a message is displayed on the
multi-information display
The system may be te mporarily unavailable
or may be malfunctioning.

224 4-5. Using the driving support systems
LS500_OM_OM50F54U_(U) WARNING●
When the follow-up cruising display is
displayed ( → P.225) 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 driven where the road
diverges, merges, etc.
●
Asphalt repair marks, white (yellow)
line marks, etc. are present due to road
repair. ●
Objects or patterns that could be mis-
taken for white (yellow) lines are pres-
ent on the side of the road (guardrails,
curbs, reflective poles, etc.).
●
Vehicle is being driven around a sharp
curve. ●
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.
●
Tires which differ by structure, manu-
facturer, brand or tread pattern are
used.
●
Vehicle is driven in traffic lanes other
than on highways and freeways.
■
Preventing LTA system malfunctions
and operations performed by mistake
●
Do not modify the headlights or place
stickers, etc. on the surface of the
lights.

2294-5. Using the driving support systems
LS500_OM_OM50F54U_(U) 4
Driving ●
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 surface,
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 oncoming
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 vehicle is driven around a sharp
curve.●
The traffic lane is ex cessively narrow or
wide.●
The vehicle is extremely tilted due to car-
rying heavy luggage or having improper
tire pressure.●
The distance to the preceding vehicle is
extremely short.●
The preceding vehicle changes lanes.
(Your vehicle may follow the preceding
vehicle and also change lanes.)●
The preceding vehicle is swaying. (Your
vehicle may sway accordingly and depart
from the lane.)
●
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 headlight is
dim due to its lens being dirty or it being
misaligned.
●
The vehicle is struck by a crosswind.
●
The vehicle has just changed lanes through operation of the steering wheel
by the driver or crossed an intersection. ●
Snow tires, etc. are equipped. ●
The vehicle is being driven at extremely
high speeds. ■
Warning message
If the following warning message is dis-
played on the multi-in formation display and
the LTA indicator illuminates in orange, fol-
low the appropriate troubleshooting proce-
dure.
Warning message Details/Actions
“LTA Malfunction
Visit Your Dealer” The system may not be
operating properly.
→ Have the vehicle
inspected at your
Lexus dealer.
“Front Camera
Unavailable
Remove Debris
On Windshield” Dirt, rain, condensa-
tion, ice, snow, etc., are
present on the wind-
shield in front of the
camera sensor.
→ Turn the LTA system
off, remove any dirt,
rain, condensation, ice,
snow, etc., from the
windshield, and then
turn the LTA system
back on.

2334-5. Using the driving support systems
LS500_OM_OM50F54U_(U) 4
Driving
Press the LKA switch to turn the LKA
system on.WARNING■
Before using LKA system
Do not rely solely upon the LKA system.
The LKA 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. ■
To avoid operating LKA system by
mistake
When not using the LKA system, use the
LKA switch to turn the system off. ■
Situations unsuitab le for LKA system
Do not use the LKA system in the follow-
ing situations.
The system may not operate properly
and lead to an accident, resulting in
death or serious injury.
●
A spare tire, tire chains, etc. are
equipped.
●
When the tires have been excessively
worn, or when the tire inflation pres-
sure is low.
●
Tires which differ by structure, manu-
facturer, brand or tread pattern are
used.
●
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 on a snow-covered
road.
●
White (yellow) lines are difficult to see
due to rain, snow, fog, dust, etc. ●
Asphalt repair marks, white (yellow)
line marks, etc. are present due to road
repair. ●
Vehicle is driven in a temporary lane or
restricted lane due to construction
work. ●
Vehicle is driven on a road surface
which is slippery due to rainy weather,
fallen snow, freezing, etc. ●
Vehicle is driven in traffic lanes other
than on highways and freeways. ●
Vehicle is driven in a construction
zone. ■
Preventing LKA 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.
Turning LKA system on

236 4-5. Using the driving support systems
LS500_OM_OM50F54U_(U) function is automatically restored.
( → P.235)■
Steering assist function/lane centering
function
Depending on the vehicle speed, lane
departure situation, ro ad conditions, etc.,
the driver may not feel the function is oper-
ating or the function may not operate at all.■
Lane departure alert function
The warning buzzer may be difficult to hear
due to external noise, audio playback, etc.
Also, it may be difficult to feel steering
wheel vibrations due to the road conditions,
etc. ■
Hands off steering wheel alert
When the system determines that the driver
has removed the hands from the steering
wheel while the steering assist function or
lane centering function is operating, a warn-
ing message is displaye d on the multi-infor-
mation display. If the driver continues to
keep the hands off of the steering wheel, a
warning message is displayed and the func-
tion is temporarily canceled. This alert also
operates in the same way when the driver
continuously operates the steering wheel
only a small amount. However, depending
on the road conditions , etc., the function
may not cancel. ■
White (yellow) lines ar e only on one side
of road
The LKA system will not operate for the
side on which white (yellow) lines could not
be recognized. ■
Conditions in whic h functions may not
operate properly
In the following situations, the camera sen-
sor may not detect white (yellow) lines and
various functions may not operate normally.
●
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 intersec-
tion, 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 reco gnize than lines that
are white). ●
The white (yellow) lines cross over a curb,
etc. ●
The vehicle is driven on a bright surface,
such as concrete. ●
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 sudd enly, such as at
the entrances and exits of tunnels, etc. ●
Light from the headlights of an oncoming
vehicle, the sun, etc. enters the camera. ●
The vehicle is driven where the road
diverges, merges, etc. ●
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 vehicle is driven around a sharp
curve. ●
The traffic lane is excessively narrow or
wide. ●
The vehicle is extremely tilted due to car-
rying 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).
●
The headlight lenses are dirty and emit a
faint amount of light at night, or the beam
axis has deviated.
●
The vehicle is struck by a crosswind.
●
The vehicle has just changed lanes or
crossed an intersection.
●
Snow tires, etc. are equipped.

240 4-5. Using the driving support systems
LS500_OM_OM50F54U_(U) *
: Displayed when speed limit information for th e road is available from the navigation sys-
tem
In the following situations, the RSA sys-
tem will alert the driver.
When the vehicle speed exceeds
the speed warning threshold of the
speed limit sign displayed, the sign
display will be emphasized and a
buzzer will sound.
When the RSA system recognizes a
do not enter sign and determines
that your vehicle has entered a
no-entry area, the displayed sign will
flash and a buzzer will sound.
Depending on the situation, traffic
environment (traffic direction, speed,
unit) may be detected incorrectly and a
warning display may not operate prop-
erly. ■
Turning the system on/off
1 Select on of the
multi-information display ( → P.76)
2 Press on the steering wheel.
■
Automatic turn-off of RSA sign display
In the following situations, a displayed
speed limit sign will stop being displayed
automatically:
●
A new sign is not recognized for a certain
distance. (When speed limit information
is not available from the navigation sys-
tem)
In the following situations, do not enter, stop
and yield signs will st op being displayed
automatically:
●
The system determines that your vehicle
has passed the sign.
●
The road changes due to a left or right turn, etc. ■
Conditions in which the function may
not operate or detect correctly
In the following situations, RSA does not
operate normally and may not recognize
signs, display the incorrect sign, etc. How-
ever, this does not indicate a malfunction. ●
The camera sensor is misaligned due to a
strong impact being applied to the sen-
sor, etc. ●
Dirt, snow, stickers, etc. are on the wind-
shield near the camera sensor. ●
In inclement weather such as heavy rain,
fog, snow or sand storms ●
Light from an oncoming vehicle, the sun,
etc. enters the camera sensor. ●
The sign is dirty, faded, tilted or bent. ●
All or part of the sign is hidden by the
leaves of a tree, a pole, etc. ●
The sign is only visible to the camera sen-
sor for a short amount of time. ●
The driving scene (turning, lane change,
etc.) is judged incorrectly. ●
Even if it is a sign not appropriate for the
currently traveled lane, such a sign exists
directly after a freeway branches, or in an
adjacent lane just before merging. ●
Stickers are attached to the rear of the
preceding vehicle. ●
A sign resembling a system compatible
sign is recognized. ●
The front of the vehicle is raised or low-
ered due to the carried load.
●
The surrounding brightness is not suffi-
cient or changes suddenly.
●
When a sign intended for trucks, etc. is
recognized.
●
The navigation system map data is old.
●
The navigation system is not operating.
●
Side road speed signs may be detected
and displayed (if positioned in sight of the
camera sensor) while the vehicle is trav-
eling on the main road.Warning indication