
2174-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving • If a vehicle ahead is carrying a load which
protrudes past its rear bumper
• If a vehicle ahead has extremely high
ground clearance
• If a vehicle ahead is irregularly shaped,
such as a tractor or side car
• If the sun or other light is shining directly
on a vehicle or guardrail ahead
• If a vehicle cuts in front of your vehicle or
emerges from beside a vehicle
• If a vehicle ahead makes an abrupt
maneuver (such as sudden swerving,
acceleration or deceleration)
• When suddenly cutting behind a preced-
ing vehicle
• When a vehicle ahead is not directly in
front of your vehicle
• When driving in incl ement weather such
as heavy rain, fog, snow or a sandstorm
• When the vehicle is hit by water, snow,
dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When driving in a place where the sur-
rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• When a very bright light, such as the sun or the headlights of oncoming traffic,
shines directly into the camera sensor
• When driving in a location where there
are many objects which reflect radar,
such as a tunnel or parking garage
• When driving at night or in a tunnel with
the headlights off
• When the surrounding area is dim, such
as at dawn or dusk, or while at night or in
a tunnel
• After the hybrid system has started the
vehicle has not been driven for a certain
amount of time
• While making a left/r ight turn and for a
few seconds after making 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 camera
sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely
high speeds.
• When driving on a hill
• If a sensor is misaligned
• If the headlights are misaligned
• When approaching a guardrail at a wide
or narrow angle
• When a vehicle approaches your vehicle
from the front left or right side while your
vehicle is entering an intersection with
poor visibility
• When a vehicle approaches your vehicle
from the rear left or right side
• When a vehicle approaches the side of
your vehicle at a shallow angle
• When driving on a road with a grade that
changes sharply (sha rp incline/decline)
●
In some situations, such as the following,
the sensors may not detect the lane lines
or a safe space the vehicle can be steered

218 4-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) into, preventing the ac tive steering assist
from operating properly:
• 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 more wide or narrow
than normal
• When there is a light and dark pattern on
the road surface , such as due to road
repairs
• If the system determines that a collision
can be avoided by only using the brakes
• When a pedestrian is detected near the
centerline of the vehicle●
In some situations such as the following,
sufficient braking force 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
• If there are deep ruts in the road
• When driving on a slope
• When driving on a horizontally slanted
road●
Some pedestrians and bicyclists, such as
the following, may not be detected by the
sensors, preventing the system from
operating properly:
• Pedestrians and bicyclists shorter than
approximately 3.2 ft. (1 m) or taller than
approximately 6.5 ft. (2 m)
• Bicyclists riding on unusual bicycles
(bicycles for small children, tricycles,
folding bicycles, BMX bicycles, tandem
bicycles, etc.)
• Pedestrians and bicyclists who are wear-
ing white and look extremely bright
• Pedestrians and bicyclists which are not
illuminated by the headli ghts at night, in a
tunnel, etc.
• Pedestrians whose clothing appears to
be nearly the same co lor or brightness as
their surroundings
• Pedestrians and bicy clists near walls,
fences, guardrails, or large objects • Pedestrians and bicyclists which are on a
metal object (manhole cover, steel plate,
etc.) on the road
• Pedestrians and bicyclists which are mov-
ing fast
• Pedestrians and bicyclists which change
speed or direction abruptly
• Pedestrians and bicyclists which suddenly
emerge from behind a vehicle or large
object
• Pedestrians and bicyclists which are
extremely close to the side of the vehicle
(outside rear view mirror, etc.)
• Pedestrians and bicyclists wearing over-
sized clothing, such as a rain coat, long
skirt, etc., making their silhouette obscure
• Pedestrians and bicyclists who are carry-
ing large baggage, ho lding an umbrella,
etc., hiding part of their body
• Pedestrians and bicyclists behind an
object that hides part of their body
• Pedestrians and bicyclists who are bend-
ing forward or squatting
• Pedestrians who are pushing a stroller,
wheelchair, bicycle or other vehicle
• Groups of pedestrians/bicyclists which
are close together ●
Some guardrails, such as the following,
may not be detected by the sensors, pre-
venting the system from operating prop-
erly:
• Guardrails which are less than approxi-
mately 1.9 ft. (60 cm) tall
• Short guardrails
• Irregularly-shaped gu ardrails (wire cable
guardrails, guardrails made of thin poles,
etc.)
• Guardrails which are not illuminated by
the headlights at nigh t, in a tunnel, etc.
• Guardrails which appear to be nearly the
same color or brightness as their sur-
roundings
• Guardrails which appear to be nearly the
same shape as their surroundings (walls,
etc.)
• Guardrails which are over a metal object
(manhole cover, steel plate, etc.)
• Guardrails which are hidden behind thick
grass
• Guardrails which are extremely close to
the side of the vehicle (outside rear view
mirror, etc.)
• Curved guardrails or guardrails at the
entrance of a curve

2194-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving ●
In some situations such as the following,
the system may detect a pedestrian and
display a warning on the head-up display,
even though no pedestrian exists:
• If the front of the vehicle is raised or low-
ered, such as when the road surface is
uneven or undulating (due to ruts, etc.)
• When driving on a slope
• When driving on a horizontally slanted
road
• If the driver’s posture (driver seat posi-
tion) is extreme, such as excessively
reclined
• If the head-up display position is set
extremely high■
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 a sensor or the area around a sen-
sor is hot, such as in the sun
• When a sensor or the area around a sen-
sor is cold, such as in an extremely cold
environment
• When a 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.324)
• 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 ligh t 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.302), the
pre-collision brake assist and pre-colli- sion braking 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.

222 4-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) ■
Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( → P.86) of
the multi-information display. The system is automa tically enabled each
time the power switch is turned to 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.86) of the
multi-information display. The operation timing setting is retained
when the power switch is turned off.
1 Far The warning will begin to operate earlier
than with the default timing.
2 MiddleWARNING●
When transporting the vehicle via
truck, boat, train or similar means of
transportation●
When the vehicle is raised on a lift with
the hybrid system on 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 camera
sensor is temporarily installed to the
vehicle
Changing settings of the pre-col-
lision system

2254-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving road or a wall that may be mistaken for a
vehicle or pedestrian
• 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, electric power plant, or
other location where strong radio waves
or electrical noise may be present■
Situations in which the system may not
operate properly●
In some situations such as the following, a
vehicle may not be detected by the radar
sensor and camera sensor, preventing
the system from operating properly:
• If an oncoming vehicle is approaching
your vehicle
• If a vehicle ahead is a motorcycle or bicy-
cle
• When approaching the side or front of a
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 is carrying a load which
protrudes past its rear bumper
• If a vehicle ahead has extremely high
ground clearance
• If a vehicle ahead is irregularly shaped,
such as a tractor or side car
• If the sun or other light is shining directly
on a vehicle ahead
• If a vehicle cuts in front of your vehicle or emerges from beside a vehicle
• If a vehicle ahead makes an abrupt
maneuver (such as sudden swerving,
acceleration or deceleration)
• When suddenly cutting behind a preced-
ing vehicle
• When a vehicle ahead is not directly in
front of your vehicle
• When driving in incl ement weather such
as heavy rain, fog, snow or a sandstorm
• When the vehicle is hit by water, snow,
dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When driving in a place where the sur-
rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• When a very bright light, such as the sun
or the headlights of oncoming traffic,
shines directly into the camera sensor
• When the surrounding area is dim, such
as at dawn or dusk, or while at night or in
a tunnel
• After the hybrid system has started the
vehicle has not been driven for a certain
amount of time
• While making a left/r ight turn and for a
few seconds after making 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 camera
sensor

226 4-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) • 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.324)
• 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.302), the
pre-collision brake assist and pre-colli-
sion braking 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.

228 4-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) ●
Setting for “PCS” and “CAUTION” in
( → P.86) of the multi-information
display.●
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.)

2294-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving ●
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 hybrid syst em 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.