brake LEXUS LS500H 2018 Service Manual

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.

220 4-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) ■
Pre-collision warning
When the system determines that the
possibility of a frontal collision is high, a
buzzer will sound and a warning mes-
sage will be displayed on the
multi-information display to urge the
driver to take evasive action. ■
Pre-collision brake assist
When the system determines that the
possibility of a frontal collision is high,
the system applies greater braking
force in relation to how strongly the
brake pedal is depressed. ■
Pre-collision braking
When the system determines that the
possibility of a frontal collision is high,
the system warns the driver. If the sys-
tem determines that the possibility of a
frontal collision is extremely high, the
brakes are automatically applied to
help avoid the collision or reduce the
collision speed. ■
Pre-collision seatbacks (front pas-
senger’s seat / power rear seat [if
equipped])
If the system determines that the possi-
bility of a frontal collision is high, it may
move the seatbacks of the front pas-
senger’s seat and power rear seats to
the upright position automatically, if
reclined. If a seat is being adjusted, it may not be
moved by the pre-collis ion seat function.
■
Suspension control
When the system determines that the
possibility of a frontal collision is high, PCS (Pre-Collision System)
(vehicles with Lexus Safety
System+) The pre-collision system uses a
radar sensor and camera sensor to
detect vehicles and pedestrians in
front of your vehicle. When the sys-
tem determines that the possibility
of a frontal collision with a vehicle
or pedestrian is high, a warning
operates to urge the driver to take
evasive action and the potential
brake pressure is increased to help
the driver avoid the collision. If the
system determines that the possi-
bility of a frontal collision with a
vehicle or pedestrian is extremely
high, the brakes are automatically
applied to help avoid the collision or
help reduce the impact of the colli-
sion.
The pre-collision system can be dis-
abled/enabled and the warning tim-
ing can be changed. ( → P.222)
System functions

2214-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving the Adaptive Variable Suspension Sys-
tem ( → P.303) will control the damp-
ing force of the shock absorbers to
help maintain an appropriate vehicle
posture. ■
Steering control
When the system determines that the
possibility of a frontal collision is high
and the driver is operating the steering
wheel, the LDH system ( → P.303) will
control the turning angle of the front
and rear wheels and effort necessary
to turn the steering wheel to help
enhance steering responsiveness. WARNING■
Limitations of the pre-collision system●
The driver is solely responsible for safe
driving. Always drive safely, taking
care to observe your surroundings.
Do not use the pre-collision system
instead of normal braking operations
under any circumstances. This system
will not prevent collisions or lessen col-
lision damage or injury in every situa-
tion. Do not overly rely on this system.
Failure to do so may lead to an acci-
dent, resulting in death or serious
injury.
●
Although this system is designed to
help avoid a collision or help reduce
the impact of the coll ision, its effective-
ness may change according to various
conditions, therefore the system may
not always be able to achieve the same
level of performance.
Read the following conditions care-
fully. Do not overly rely on this system
and always drive carefully.
• Conditions under which the system
may operate even if there is no possi-
bility of a collision: → P.223
• Conditions under which the system
may not operate properly: → P.225 ●
Do not attempt to test the operation of
the pre-collision system yourself, as the
system may not operate properly, pos-
sibly leading to an accident. ■
Pre-collision braking ●
When the pre-collision braking func-
tion is operating, a large amount of
braking force will be applied. ●
If the vehicle is stopped by the opera-
tion of the pre-collision braking func-
tion, the pre-collision braking function
operation will be canceled after
approximately 2 seco nds. Depress the
brake pedal as necessary. ●
The pre-collision braking function may
not operate if certain operations are
performed by the driver. If the acceler-
ator pedal is being depressed strongly
or the steering wheel is being turned,
the system may determine that the
driver is taking evasive action and pos-
sibly prevent the pre-collision braking
function from operating. ●
In some situations, while the pre-colli-
sion braking function is operating,
operation of the function may be can-
celed if the accelerator pedal is
depressed strongly or the steering
wheel is turned and the system deter-
mines that the driver is taking evasive
action.
●
If the brake pedal is being depressed,
the system may determine that the
driver is taking evasive action and pos-
sibly delay the operat ion timing of the
pre-collision braking function.
■
When to disable the pre-collision sys-
tem
In the following situations, disable the
system, as it may not operate properly,
possibly leading to an accident resulting
in death or serious injury:
●
When the vehicle is being towed
●
When your vehicle is towing another
vehicle

2234-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving This is the default setting.
3 NearThe warning will begin to operate later
than with the default timing. ■
Operational conditions
The pre-collision system is enabled and the
system determines that the possibility of a
frontal collision with a vehicle or pedestrian
is high.
Each function is operat ional at the following
speeds: ●
Pre-collision warning:
• Vehicle speed is be tween approximately
7 and 110 mph (10 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 7 and 50 mph
[10 and 80 km/h].)
• The relative speed between your vehicle
and the vehicle or pedestrian ahead is
approximately 7 mph (10 km/h) or more.●
Pre-collision brake assist:
• Vehicle speed is be tween approximately
20 and 110 mph (30 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 20 and 50 mph
[30 and 80 km/h].)
• The relative speed between your vehicle
and the vehicle or pedestrian ahead is
approximately 20 mph (30 km/h) or
more.●
Pre-collision braking:
• Vehicle speed is be tween approximately
7 and 110 mph (10 and 180 km/h). (For
detecting a pedestrian, vehicle speed is
between approximately 7 and 50 mph
[10 and 80 km/h].)
• The relative speed between your vehicle
and the vehicle or pedestrian ahead is
approximately 7 mph (10 km/h) or more.
The system may not operate in the following
situations:
●
If a 12-volt battery terminal has been dis-
connected and reconnected and then the
vehicle has not been driven for a certain
amount of time
●
If the shift position is in R
●
If VSC is disabled (only the pre-collision
warning function will be operational) ■
Pedestrian detection function
The pre-collision system detects pedestri-
ans based on the size, profile, and motion of
a detected object. However, a pedestrian
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.225)
■
Cancelation of the pre-collision braking
If either of the follo wing 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. ■
Conditions under which the system may
operate even if there is no possibility of a
collision ●
In some situations su ch as the following,
the system may determine that there is a
possibility of a frontal collision and oper-
ate.
• When passing a vehicle or pedestrian
• When changing lanes while overtaking a
preceding vehicle
• When overtaking a preceding vehicle
that is changing lanes
• When overtaking a preceding vehicle
that is making a left/right turn

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.

2274-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving *
:If equipped
When the system detects a vehicle
approaching from the left or right in
front of your vehicl e 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  Multi-information display
■
The FCTA function is operational when
The system operates when all of the follow-
ing conditions are met.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 WARNING■
Cautions regarding the use of the
function
The driver is solely responsible for safe
driving. Always drive safely, taking care
to observe your surroundings.
The FCTA system is a supplementary
system that informs the driver of vehicles
approaching from the left and right of the
front of the vehicle.
Do not overly rely on the FCTA system.
Over reliance on the system may lead to
an accident, resulting in death or serious
injury.
The details of the warning display may
differ from the actual traffic conditions.
Although the warning display will stop
being displayed after a certain amount of
time, this does not indicate that vehicles
or pedestrians are no longer around your
vehicle.

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.)

2534-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) 4
Driving This mode employs a radar sensor to detect the presence of vehicles up to approx-
imately 328 ft. (100 m) ahead, determines the current vehicle-to-vehicle following
distance, and operates to maintain a suit able following distance from the vehicle
ahead. Note that vehicle-to-vehicle di stance will close in when trav eling on long downhill slopes.
Example of constant speed cruising
When there are no vehicles aheadThe vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle distance
can also be set by operating the ve hicle-to-vehicle distance switch.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appearsWhen 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 sy stem 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 decelera te 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 will resume follow-up cruising.
Vehicles with Lexus Safety System+A: If your vehicle is being driven at approximately 43
mph (70 km/h) or more, when the turn signal is operated and a lane change is made to
pass the vehicle ahead, the system will start acce lerating your vehicle up to the set speed to
assist smooth overtaking.
Example of acceleration
When there are no longer any preceding vehicles driving slower than the set Driving in vehicle-to-vehicle distance control mode
A
B
C

256 4-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) After the vehicle ahead of you starts
off, press the “+RES” switch.
Your vehicle will also resume follow-up
cruising if the accelerator pedal is
depressed after the vehicle ahead of
you starts off. 1 Pressing the cancel switch cancels
the speed control. The speed control is also canceled when
the brake pedal is depressed.
(When the vehicle has been stopped by
system control, depressing the brake pedal
does not cancel the setting.)
2 Pressing the “+RES” switch
resumes the cruise control and
returns vehicle speed to the set
speed. However, when a vehicle ahead is not
detected, cruise control does not resume
when the vehicle speed is approximately
25 mph (40 km/h) or less.
When your vehicle is too close to a
vehicle ahead, and sufficient automatic
deceleration via the cruise control is
not possible, the display will flash and
the buzzer will sound to alert the driver.
An example of this would be if another
driver cuts in front of you while you are
following a vehicle. Depress the brake
pedal to ensure an appropriate vehi-Medium Approximately 130 ft. (40
m)
Short Approximately 100 ft. (30
m)
Resuming follow-up cruising
when the vehicle has been
stopped by system control (vehi-
cle-to-vehicle distance control
mode) Distance
options Vehicle-to-vehicle dis-
tance
Canceling and resuming the
speed control
Approach warning (vehi-
cle-to-vehicle distance control
mode)

258 4-5. Using the driving support systems
LS500h_OM_OM50F42U_(U) by using the paddle shift switch.●
Vehicle speed is at or above approxi-
mately 30 mph (50 km/h).
However, when a preceding vehicle is
detected, the dynamic radar cruise con-
trol with full-speed range can be set even
if the vehicle speed is below approxi-
mately 30 mph (50 km/h).■
Accelerating after setting the vehicle
speed
The vehicle can accelerate by operating the
accelerator pedal. After accelerating, the
set speed resumes. However, during vehi-
cle-to-vehicle distance control mode, the
vehicle speed may decrease below the set
speed in order to maintain the distance to
the preceding vehicle. ■
When the vehicle stops while follow-up
cruising●
Pressing the “+RES” switch while the
vehicle ahead stops w ill resume follow-up
cruising if the vehicle ahead starts off
within approximately 3 seconds after the
switch is pressed.●
If the vehicle ahead starts off within 3 sec-
onds after your vehicle stops, follow-up
cruising will be resumed.■
Automatic cancelation of vehi-
cle-to-vehicle distance control mode
Vehicle-to-vehicle dist ance control mode is
automatically canceled in the following situ-
ations. ●
Actual vehicle speed falls at or below
approximately 25 mph (40 km/h) when
there are no vehicles ahead.●
The preceding vehicle leaves the lane
when your vehicle is following at a vehicle
speed at or below approximately 25 mph
(40 km/h). Otherwise, the sensor cannot
properly detect the vehicle. (“CRUISE
NOT AVAILABLE No Preceding Vehi-
cles” is displayed on the multi-information
display.)
●
VSC is activated.
●
TRAC is activated for a period of time.
●
When the VSC or TRAC system is
turned off.
●
When snow mode is set. ●
The sensor cannot detect correctly
because it is covered in some way. ●
Pre-collision braking is activated. ●
The parking brake is operated. ●
The vehicle is stopped by system control
on a steep incline. ●
The following are detected when the
vehicle has been stopped by system con-
trol:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3
minutes.
If vehicle-to-vehicle distance control mode
is automatically canceled for any other rea-
son, there may be a malfunction in the sys-
tem. Contact your Lexus dealer. ■
Automatic cancelation of constant
speed control mode
Constant speed control mode is automati-
cally canceled in the following situations: ●
Actual vehicle speed is more than
approximately 10 mph (16 km/h) below
the set vehicle speed. ●
Actual vehicle speed falls below approxi-
mately 25 mph (40 km/h). ●
VSC is activated. ●
TRAC is activated for a period of time. ●
When the VSC or TRAC system is
turned off. ●
Pre-collision braking is activated.
If constant speed control mode is automati-
cally canceled for any other reason, there
may be a malfunction in the system. Con-
tact your Lexus dealer.
■
If “Radar Cruise Control Unavailable” is
shown on the multi-information display
The radar cruise control system cannot be
used temporarily. Use the system when it
becomes available again.
■
Brake system operation sound
When the brakes are operated in vehi-
cle-to-vehicle distance mode, a brake oper-
ating sound may be heard. This is not a
malfunction.