warning light LEXUS LS500H 2019 Workshop Manual

2154-5. Using the driving support systems
LS500h_OM_(U)_1809
4
Driving
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.90) 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.
If the pre-collision sy stem is disabled,
the pedestrian alert system will also be
disabled. At this time, the FCTA (Front
Cross Traffic Alert) ( P.230) system
will also be disabled.
■Enabling/Disabling the pedestrian
alert system
The pedestrian alert can be
enabled/disabled on ( P.90) of
the multi-information display. At this
time, the FCTA (Front Cross Traffic
Alert) system will also be enabled/dis-
abled.
WARNING
●When your vehicle is towing another
vehicle
●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 has been
applied to the front bumper, rear
bumper or front grille, due to an acci-
dent 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 a radar sensor or the front
camera is temporarily installed to the
vehicle
Changing settings of the pre-col-
lision system

2224-5. Using the driving support systems
LS500h_OM_(U)_1809
●In some situations, such as the following,
the sensors may not detect the lane lines
or a safe space the vehicle can be steered
into, preventing the active 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 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 guardrails (wire cable guardrails, guardrails made of thin poles,
etc.)
• Guardrails which are not illuminated by the headlights at night, 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
●In some situations su ch 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 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.

2254-5. Using the driving support systems
LS500h_OM_(U)_1809
4
Driving
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.90) 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.90) of the
multi-information display.
The warning timing setting is retained
when the power 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).
WARNING
●When your vehicle is towing another
vehicle
●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 front cam-
era is temporarily installed to the vehi-
cle
Changing settings of the pre-col-
lision system

2304-5. Using the driving support systems
LS500h_OM_(U)_1809• 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
●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
■If VSC is disabled
●If VSC is disabled ( P.303), 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.
*: If equipped
When the system detects a vehicle
approaching from the left or right in
front of your vehicle when approaching
an intersection, a notification will be
displayed on the head-up display and
panoramic view monitor
*.
*: Refer to “NAVIGATION AND MULTI-
MEDIA SYSTEM OWNER’S MAN-
UAL”.
When the system determines that your
vehicle may be about to enter an inter-
section even though a vehicle is
approaching from the left or right in
front of your vehicle, a buzzer will
sound and a message will be displayed
on the multi-information display to
urge you to depress the brake pedal.
 Head-up display
FCTA (Front Cross Traffic
Alert)*
When approaching an intersection
at low speed, the radar sensors on
the front side of the vehicle can
detect approaching vehicles to the
left and right of the front of the vehi-
cle. In this case, the head-up display
is used to inform the driver of
detected vehicles.
FCTA system functions

2334-5. Using the driving support systems
LS500h_OM_(U)_1809
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

2344-5. Using the driving support systems
LS500h_OM_(U)_1809
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.

2364-5. Using the driving support systems
LS500h_OM_(U)_1809
■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 curb
WARNING
●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

2424-5. Using the driving support systems
LS500h_OM_(U)_1809cle speed is less than approximately 32
mph (50 km/h) when the lane center-
ing function is operating.
*2: Boundary between asphalt and the side
of the road, such as grass, soil, or a curb
●Steering assist function
This function operates when all of the fol-
lowing conditions are me t in addition to the
operation conditions for the lane depar-
ture alert function.
•Setting for “Steering Assist” in of the multi-information display is set to “ON”.
( P.90)
• Vehicle is not accelerated or decelerated by a fixed amount or more.
• Steering wheel is not operated with a
steering force level su itable for changing
lanes.
• ABS, VSC, TRAC and PCS are not oper-
ating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning is not displayed. ( P.244)
●Vehicle sway warning function
This function operates when all of the fol-
lowing conditions are met.
• Setting for “Sway Warning” in of the multi-information display is set to “ON”.
( P.90)
• Vehicle speed is approximately 32 mph (50 km/h) or more.
• Width of traffic lane is approximately 9.8
ft. (3 m) or more.
• No system malfunctions are detected. ( P.245)
●Lane centering function
This function operates when all of the fol-
lowing conditions are met.
• LTA is turned on.
• Setting for “Steering Assist” and “Lane Center” in of the multi-information
display are set to “ON”. ( P.90)
• This function recognizes white (yellow)
lane lines or the position of a preceding
vehicle (except when the preceding vehi-
cle is small, such as a motorcycle).
• The dynamic radar cruise control with full-speed range is operating in vehi-
cle-to-vehicle distance control mode.
• Width of traffic lane is approximately 10
to 13 ft. (3 to 4 m).
• Turn signal lever is not operated.
• Vehicle is not being driven around a sharp curve.
• No system malfunctions are detected. ( P.245)
• Vehicle does not ac celerate or deceler-
ate by a fixed amount or more.
• Steering wheel is not operated with a
steering force level su itable for changing
lanes.
• ABS, VSC, TRAC and PCS are not oper-
ating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning is not displayed. ( P.244)
• The driver has one or both hands on the steering wheel.
• The vehicle is being driven in the center of a lane.
• Steering assist function is not operating.
●Lane change assist fu nction (vehicles with
Lexus Safety System + A)
This function will operate when all of the
following conditions are met:
• The lane centering function is operating.
• “Lane Change Assist” is set to “ON” in of the multi-information dis-
play.( P.90)
• The vehicle speed is between approxi- mately 57 and 85 mph (90 and 140
km/h).
• White (yellow) lane lines are detected by
the system.
• A broken white line is detected between your vehicle and the lane toward which
the turn signal is operated.
• The turn signal lever is held partway (lane change position) for approximately 1 sec-
ond.
• A vehicle is not overtaking your vehicle
or detected in the lane toward which the
turn signal is operated.
• The vehicle is being driven straight or
around a slight curve.
• The vehicle is not a ccelerating or decel-
erating more than a certain amount.
• The steering wheel is not being turned sufficiently to perf orm a lane change.

2444-5. Using the driving support systems
LS500h_OM_(U)_1809operating, if the system detects that a vehi-
cle is quickly approaching in the lane
toward which the turn signal is operated,
the steering assist may slightly steer the
vehicle away from the lane while a buzzer is
sounding, the steering
wheel is vibrating,
and a warning display is displayed on the
multi-information display, to help prevent
the vehicle from entering the lane and alert
the driver of the approaching vehicle.
■Hands off steering wheel alert
In the following situations, a warning mes-
sage urging the driver to hold the steering
wheel and the symbol shown in the illustra-
tion are displayed on the multi-information
display to warn the driver. The warning
stops when the system determines that the
driver holds the steering wheel. Always
keep your hands on the steering wheel
when using this system, regardless of warn-
ings.
Depending on the vehicle condition and
road conditions, the warning may not oper-
ate. Also, if the system determines that the
vehicle is driving around a curve, warnings
will occur earlier than during straight-lane
driving.
●When the system determines that the
driver is driving without holding the steer-
ing wheel while the sy stem is operating
If the driver continue s to keep their hands
off of the steering wheel, the buzzer
sounds, the driver is warned and the func-
tion is temporarily ca nceled. This warning
also operates in the same way when the
driver continuously operates the steering
wheel only a small amount.
The buzzer also sounds even if the alert
type is set to .
●When the system determines that the
vehicle may not turn and instead depart
from its lane while driving around a curve
(vehicles with Lexus Safety System + 2.0)
●When the system determines that the
driver is driving with out holding the steer-
ing wheel while the st eering wheel assist
of the steering assist function is operating
(vehicles with Lexus Safety System + 2.0)
If the driver continues to keep their hands
off of the steering wheel and the steering
wheel assist is operating, the buzzer
sounds and the driver is warned. Each time
the buzzer sounds, the continuing time of
the buzzer becomes longer.
The buzzer also sounds even if the alert
type is set to .
In situations such as the following, the sys-
tem may not be able to detect when the
driver’s hands are on the steering wheel
(vehicles with Lexus Safety System + A):
●If a steering wheel cover is installed.
●If the driver is wearing gloves.
●If something is attached to the steering
wheel.
●If the driver is gripping the wood trim,
stitched area, spokes, or other part of the
steering wheel that does not have sen-
sors.
In situations such as the following, the hands
off steering wheel alert may not operate
and the steering assist function and lane
centering function may operate even if the
driver’s hands are off the steering wheel
(vehicles with Lexus Safety System + A):
●If an object contacts the steering wheel.
●If a wide object or ar ms are held in front
of the steering wheel.
■Vehicle sway warning function
When the system determines that the vehi-
cle is swaying while the vehicle sway warn-
ing function is operating, a buzzer sounds
and a warning message urging the driver to
rest and the symbol sh own in the illustration
are simultaneously displayed on the
multi-information display.

2484-5. Using the driving support systems
LS500h_OM_(U)_1809
This mode employs a radar to detect the presence of vehicles up to approximately
328 ft. (100 m) ahead, determines the cu rrent vehicle-to-vehicle following dis-
tance, and operates to maintain a suitab le following distance from the vehicle
ahead. The desired vehicle-to-vehicle distance can also be set by operating the
vehicle-to-vehicle distance switch.
When driving on downhill slopes, the vehicl e-to-vehicle distance may become shorter.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appears
When a vehicle is detected running ahead of you, the system automatically decelerates
your vehicle. When a greater reduction in vehicle speed is necessary, the system applies
the brakes (the stop lights will come on at this time). The system will respond to changes in
the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle distance set by
the driver. Approach warning warns you when th e system cannot decelerate sufficiently to
prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehi cle will also stop (vehicle is stopped by sys-
tem control). After the vehicle ahead starts off, pressing the “+RES” switch or depressing
the accelerator pedal (start-off operation) will resume follow-up cruising. If the start-off
operation is not performed, system contro l continues to keep your vehicle stopped.
When the turn signal lever is operated and your vehicle moves to a left lane while driving at
50 mph (80 km/h) or more, the vehicle will quickly accelerate to help to overtake a pass-
ing vehicle.
Example of acceleration
Driving in vehicle-to-vehicle distance control mode
A
B
C