brake LEXUS LS500 2021 Repair Manual

2914-5. Using the driving support systems
4
Driving
traveling direction of the vehicle.
■Re-enabling the Parking Support Brake
function (static objects)
 P.287
■Detection range of the Parking Support
Brake function (static objects)
The detection range of the Parking Support
Brake function (static objects) differs from
the detection range of the intuitive parking
assist. ( P.276) Therefore, even if the intui-
tive parking assist de tects an object and
provides a warning, the Parking Support
Brake function (static objects) may not start
operating.
■Objects that the Parking Support Brake
function (static obje cts) may not detect
The sensors may not be able to detect cer-
tain objects, such as the following:
●Pedestrian
●Cotton cloth, snow, and other materials
that are poor reflectors of ultrasonic
waves
●Objects which are not perpendicular to
the ground, are not perpendicular to the
traveling direction of the vehicle, are
uneven or are waving
●Low objects
●Thin objects such as wires, fences, ropes
and signposts
●Objects that are extremely close to the
bumper
●Sharply-angled objects
●Tall objects with upper sections project-
ing outwards in the direction of your vehi-
cle
■Situations in which the Parking Support
Brake function (stati c objects) may not
operate
When driving with the shift position in N
■Intuitive parking assist buzzer
Regardless of whether the intuitive parking
assist system is enabled or not ( P.273), if
the Parking Support Brake function (static
objects) is enabled ( P.285), the front or
rear sensors detect an object and brake
control is performed, the intuitive parking assist buzzer will sound to notify the driver
of the approximate distance to the object.
■Situations in which the Parking Support
Brake function (static objects) may
operate even if there is no possibility of a
collision
In some situations, such as the following, the
Parking Support Brake function (static
objects) may operate even though there is
no possibility of a collision.
●Vehicle surroundings
• When driving on a narrow road
• When driving on a gravel road or in an area with tall grass
• When driving toward a banner, flag, low-hanging branch or boom barrier
(such as those used at railroad crossings,
toll gates and parking lots)
• When driving on a narrow path sur-
rounded by a structure, such as in a tun-
nel or on an iron bridge
• When parallel parking
• When there is a rut or hole in the surface of the road
• When driving on a metal cover (grating), such as those used for drainage ditches
• When driving on a steep slope
• If a sensor is hit by a large amount of
water, such as when driving on a flooded
road
●Weather
• If a sensor is covered with ice, snow, dirt, etc. (when cleared, the system will return

2924-5. Using the driving support systems
to normal)
• If heavy rain or water strikes a sensor
• When driving in incl ement weather such
as fog, snow or a sandstorm
• When strong winds are blowing
●Other ultrasonic wave sources
• When vehicle horns, vehicle detectors, motorcycle engines, air brakes of large
vehicles, the clearance sonar of other
vehicles or other devices which produce
ultrasonic waves are near the vehicle
• If a sticker or an el ectronic component,
such as a backlit license plate (especially
fluorescent type), fog lights, fender pole
or wireless antenna is installed near a
sensor
●Changes in the vehicle posture
• If the vehicle is significantly tilted
• If the front of the vehicle is raised or low- ered due to the carried load
• If the orientation of a sensor has been changed due to a collision or other
impact
■Situations in which the Parking Support
Brake function (stati c objects) may not
operate properly
In some situations, such as the following, this
function may not operate properly.
●Weather
• When a sensor or the area around a sen-
sor is extremely hot or cold
• When strong winds are blowing
• If a sensor is covered with water drops, ice, snow, dirt, etc. (when cleared, the sys-
tem will return to normal)
• If heavy rain or water strikes a sensor
• When driving in incl ement weather such
as fog, snow or a sandstorm
• When the sensor is frozen (Once the
sensor thaws, the system will return to
normal)
●Vehicle surroundings
• When an object that cannot be detected is between the vehicle and a detected
object
• If an object such as a vehicle, motorcycle, bicycle or pedestrian cuts in front of the
vehicle or runs out from the side of the
vehicle
• The vehicle is approaching a tall or
curved curb.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• If objects draw too close to the sensor.
●Other ultrasonic waves sources
• When vehicle horns, vehicle detectors, motorcycle engines, air brakes of large
vehicles, the clearance sonar of other
vehicles or other de vices which produce
ultrasonic waves are near the vehicle
• If a sticker or an electronic component,
such as a backlit license plate (especially
fluorescent type), fog lights, fender pole
or wireless antenna is installed near a
sensor
●Changes in the vehicle posture
• If the vehicle is significantly tilted
• If the front of the vehicle is raised or low- ered due to the carried load
• If the orientation of a sensor has been
changed due to a collision or other
impact
• When equipment that may obstruct a sensor is installed, such as a towing eye-
let, bumper protector (an additional trim
strip, etc.), bicycle carrier, or snow plow
• If the suspension has been modified or tires of a size othe r than specified are
installed
• If a sensor has been painted or covered with a sticker, etc.

2934-5. Using the driving support systems
4
Driving
*:If equipped
This function will operate in situations
such as the following if a vehicle is
detected in the traveling direction of
the vehicle.
When reversing, a vehicle is
approaching and the brake pedal is
not depressed, or is depressed late
 P.267
■The Parking Support Brake function
(rear-crossing vehicles) will operate
when
The function will operate when the PKSB
OFF indicator is not illuminated ( P.72)
and all of the following conditions are met:
●Engine output restriction control
• The Parking Support Brake is enabled.
• The vehicle speed is 9 mph (15 km/h) or less.
• Vehicles which are ap proaching from the
right or left at the rear of the vehicle at a
traveling speed of approximately 5 mph
(8 km/h) or more.
• The shift position is in R.
• The Parking Support Brake determines that a stronger than normal brake opera-
tion is necessary to avoid a collision with
an approaching vehicle.
●Brake control
• Engine output restriction control is oper-
ating.
• The Parking Support Brake determines
Parking Support Brake func-
tion (rear-crossing vehicles)*
If a rear radar sensor detects a vehi-
cle approaching from the right or
left at the rear of the vehicle and the
system determines that the possi-
bility of a collision is high, this func-
tion will perform brake control to
reduce the likelihood of an impact
with the approaching vehicle.
Examples of function operation
Types of sensors
WARNING
■To ensure the Parking Support Brake
(rear-crossing vehicles) can operate
properly
Observe the following precautions
regarding the rear side radar sensors
(  P.267). Failure to do so may cause a
sensor to not operate properly, and may
cause an accident.
●Do not modify, disassemble or paint
the sensors.
●Do not replace a rear side radar sen-
sor with a part other than a genuine
part.
●Do not damage the rear side radar
sensors, and always keep the radar
sensors and their surrounding area on
the bumper clean.
●If the area around a rear side radar
sensor is subjected to an impact, the
system may not operate properly due
to a sensor malfunction. Have the vehi-
cle inspected by your Lexus dealer.

2944-5. Using the driving support systems
that an emergency brake operation is
necessary to avoid a collision with an
approaching vehicle.
■The Parking Support Brake function
(rear-crossing vehicles) will stop operat-
ing when
The function will stop operating if any of the
following conditions are met:
●Engine output restriction control
• The Parking Support Brake is disabled.
• The collision becomes avoidable with normal brake operation.
• A vehicle is no longer approaching from the right or left at the rear of the vehicle.
●Brake control
• The Parking Support Brake is disabled.
• Approximately 2 seconds have elapsed
since the vehicle was stopped by brake
control.
• The brake pedal is depressed after the vehicle is stopped by brake control.
• A vehicle is no longer approaching from
the right or left at the rear of the vehicle.
■Re-enabling the Parking Support Brake
function (rear-crossing vehicles)
 P.287
■Detection area of the Parking Support
Brake function (rear-crossing vehicles)
The detection area of the Parking Support
Brake function (rear-crossing vehicles) dif-
fers from the detection area of the RCTA
function ( P.279). Therefore, even if the
RCTA function detects a vehicle and pro-
vides an alert, the Parking Support Brake
function (rear-crossing vehicles) may not
start operating.
■Conditions under which the Parking
Support Brake function (rear-crossing
vehicles) will not detect a vehicle
The Parking Support Brake function
(rear-crossing vehicles) is not designed to
detect the following types of vehicles and/or
objects:
●Vehicles approaching from directly
behind
●Vehicles backing up in a parking space
next to your vehicle
●Vehicles that the sensors cannot detect due to obstructions
●Vehicles which suddenly accelerate or
decelerate near your vehicle
●Guardrails, walls, signs, parked vehicles
and similar stationary objects
●Small motorcycles, bicycles, pedestrians,
etc.
●Vehicles moving away from your vehicle
●Vehicles approaching from the parking
spaces next to your vehicle
●Objects which are extremely close to a
radar sensor
●Vehicles which are approaching from the
right or left at the rear of the vehicle at a
traveling speed of less than approxi-
mately 5 mph (8 km/h)
●Vehicles which are approaching from the
right or left at the rear of the vehicle at a
traveling speed of
more than approxi-
mately 15 mph (24 km/h)
■PKSB buzzer
If the Parking Support Brake is enabled and
brake control is performed, a buzzer will
sound to notify the driver.
■Situations in which the system may
operate even though there is no possi-
bility of a collision
In some situations such as the following, the
Parking Support Brake function
(rear-crossing vehicles) may operate even
though there is no possibility of a collision.
●When the parking space faces a street
and vehicles are being driven on the
street

2954-5. Using the driving support systems
4
Driving
●When a detected vehicle turns while
approaching the vehicle
●When a vehicle passes by the side of your
vehicle
●When the distance between your vehicle
and metal objects, such as a guardrail,
wall, sign, or parked vehicle, which may
reflect electrical waves toward the rear of
the vehicle, is short
●When there are spinning objects near
your vehicle such as the fan of an air con-
ditioning unit
●When water is splashed or sprayed
toward the rear bumper, such as from a
sprinkler
■Situations in which the Parking Support
Brake function (rear-crossing vehicles)
may not operate properly
In some situations, such as the following, the
radar sensors may not detect an object and
this function may not operate properly
●Stationary objects
●When a sensor or the area around a sen-
sor is extremely hot or cold
●If the rear bumper is covered with ice,
snow, dirt, etc.
●When it is raining he avily or water strikes
the vehicle
●If the vehicle is significantly tilted
●When equipment that may obstruct a
sensor is installed, such as a towing eye-
let, bumper protector (an additional trim
strip, etc.), bicycle carrier, or snow plow
●If the suspension has been modified or
tires of a size othe r than specified are
installed
●If the front of the vehicle is raised or low-
ered due to the carried load
●If an electronic component, such as a
backlit license plate (especially fluores-
cent type), fog lights, fender pole or wire-
less antenna is installed near a radar
sensor
●If the orientation of a radar sensor has
been changed
●When multiple vehicl es are approaching
with only a small gap between each vehi-
cle
●If a vehicle is approaching the rear of
your vehicle rapidly
●Situations in which the radar sensor may
not detect a vehicle
• When a vehicle approaches from the right or left at the rear of the vehicle while
you are turning while backing up
• When turning while backing up

2964-5. Using the driving support systems
• When backing out of a shallow angle parking spot
• When backing up on a slope with a sharp change in grade
• When a vehicle turns into the detection area
*: If equipped
When a pedestrian is detected behind
the vehicle while backing up, the brake
pedal is not depressed or is depressed
late.
Displays a message to urge the driver
to take evasive action when a pedes-
trian is detected in the detection area
behind the vehicle. (A message will
also be displayed on the multi-informa-
Parking Support Brake func-
tion (rear pedestrians)*
If the rear camera sensor detects a
pedestrian behind the vehicle while
backing up and the system deter-
mines that the possibility of collid-
ing with the detected pedestrian is
high, a buzzer will sound. If the sys-
tem determines that the possibility
of colliding with the detected
pedestrian is extremely high, the
brakes will be applied automatically
to help reduce the impact of the
collision.
Examples of system operation
Center Display

2974-5. Using the driving support systems
4
Driving
tion display and head-up display [if
equipped].)Pedestrian detection icon
Brake reminder■Parking Support Brake function (rear
pedestrians) will operate when
The function will operate when the PKSB
OFF indicator is not illuminated ( P.72)
and all of the following conditions are met:
●Engine output restriction control
• The Parking Support Brake is enabled.
• The vehicle speed is 9 mph (15 km/h) or less.
• The shift position is in R.
• The rear camera sensor detects a pedes- trian behind the vehicle while backing up
and the system determines that the possi-
bility of colliding with the detected
pedestrian is high.
●Brake control
• Engine output restriction control is oper-
ating.
• The Parking Support Brake determines that an emergency brake operation is
necessary to avoid a collision with a
pedestrians.
■The Parking Support Brake function
(rear pedestrians) will stop operating
when
The function will stop operating if any of the
following conditions are met:
●Engine output restriction control
• The Parking Support Brake is disabled.
• The collision becomes avoidable with normal brake operation.
• The pedestrian is no longer detected behind your vehicle.
●Brake control
• The Parking Support Brake is disabled.
• Approximately 2 seconds have elapsed since the vehicle was stopped by brake
control.
• The brake pedal is depressed after the vehicle is stopped by brake control.
• The pedestrian is no longer detected behind your vehicle.
■Re-enabling the Parking Support Brake
function (rear pedestrians)
 P.287
■Detection area of the Parking Support
Brake function (rear pedestrians)
The detection area of the Parking Support
WARNING
■If the Parking Support Brake function
(rear pedestrians) operates unneces-
sarily
Depress the brake pedal immediately
after the Parking Support Brake function
(rear pedestrians) operates. (Operation
of the function is canceled by depressing
the brake pedal.)
■Correct use of the Parking Support
Brake function (rear pedestrians)
Do not overly rely on the Parking Sup-
port Brake function (rear pedestrians).
Depending on the road conditions, vehi-
cle conditions and weather, this function
may not operate correctly. As the detec-
tion performance of the rear camera is
limited, always drive safely, taking care to
observe your surroundings.
Additionally, if a warning message is dis-
played on the center display indicating
that the Parking Support Brake function
(rear pedestrians) is unavailable, the
function cannot be used. Even if these
warnings are not output, the driver is
always responsible for paying attention
to the vehicle’s surro undings and driving
safely.
A
B

2984-5. Using the driving support systems
Brake function (rear pedestrians) differs
from the detection area of the RCD func-
tion (P.282). Therefore, even if the RCD
function detects a pedestrian and provides
an alert, the Parking Support Brake function
(rear pedestrians) may not start operating.
■Situations in which the system may not
operate properly
●Some pedestrians, such as the following,
may not be detected by the Parking Sup-
port Brake function (rear pedestrians),
preventing the function from operating
properly:
• Pedestrians who are bending forward or squatting
• Pedestrians who are lying down
• Pedestrians who are running
• Pedestrians who suddenly enter the detection area
• People riding a bicycle, skateboard, or other light vehicle
• Pedestrians wearing oversized clothing such as a rain coat, long skirt, etc., making
their silhouette obscure
• Pedestrians whose body is partially hid- den by an object, such as a cart or
umbrella
• Pedestrians which are obscured by dark- ness, such as at night
●In some situations, such as the following,
pedestrians may not be detected by the
Parking Support Brake function (rear
pedestrians), preventing the function
from operating properly:
• When backing up in inclement weather
(rain, snow, fog, etc.)
• When the rear camera is obscured (dirt, snow, ice, etc. are attached) or scratched
• When a very bright light, such as the sun, or the headlights of another vehicle,
shines directly into the rear camera
• When backing up in a place where the surrounding brightness changes sud-
denly, such as at the entrance or exit of a
garage or underground parking lot
• When backing up in a dim environment such as during dusk or in an underground
parking lot
●Even though there are no pedestrians in
the detection area, some objects, such as
the following, may be detected, possibly
causing the Parking Support Brake func- tion (rear pedestrians) to operate.
• Three dimensional objects, such as a pole, traffic cone, fence, or parked vehi-
cle
• Moving objects, such as a car or motor- cycle
• Objects moving toward your vehicle when backing up, such as flags or pud-
dles (or airborne matter, such as smoke,
steam, rain, or snow)
• Cobblestone or gravel roads, tram rails, road repairs, white lines, pedestrian
crossings, puddles or fallen leaves on the
road
• Metal covers (gratings), such as those
used for drainage ditches
• Objects reflected in a puddle or on a wet road surface
• The roadside or bumps on the road
•Shadows on the road
●In some situations, such as the following,
the Parking Support Brake function (rear
pedestrians) may operate even though
there are no pedestrians in the detection
area.
• When backing up toward the roadside or
a bump on the road
• If the vehicle is signif icantly tilted, such as
when carrying a heavy load
• When backing up toward an incline/decline
• If the suspension has been modified or
tires of a size othe r than specified are
installed
• If the rear of the vehicle is raised or low-
ered due to the carried load
• If an electronic component, such as a backlit license plate or rear fog light, is
installed near the rear camera
• If a bumper protector, such as an addi- tional trim strip, is installed to the rear
bumper
• If the orientation of the rear camera has been changed
• If a towing eyelet is in stalled to the rear of
the vehicle
• When water is flowing over the rear cam- era lens
• When the rear camera is obscured (dirt,
snow, ice, etc. are at tached) or scratched
• If there is a flashing light in the detection
area, such as the emergency flashers of
another vehicle

3014-5. Using the driving support systems
4
Driving
*:If equipped
■Situations in which the vehicle height
control may not operate properly
●In the following situations, the vehicle
height may change slowly or may not
change to the correct height:
• When the vehicle comes into contact with snow, ice, stone, etc.
• When the ambient temperature is low
• When the accumulator tank pressure is low
●In the following situations, the vehicle
height may not change:
• If the hood or trunk is not fully closed
• If the brake pedal depressed and the
vehicle is stopped
• When the vehicle is on a significantly
uneven or undulating road
• When the vehicle is on a slanted road or a slope
■Operating sound of the air suspension
compressor and valves
In the following situations the air suspension
compressor and valves may operate and a
sound may be heard, but this does not indi-
cate a malfunction.
●When passengers enter or exit the vehi-
cle or cargo is loaded or unloaded, caus- ing the vehicle height to change
●When the height of the vehicle is
changed using the vehicle height adjust-
ment switch
●When the doors are opened/closed
●When the doors are locked/unlocked
■When the accumulator
tank pressure is
low
When the accumulator tank pressure is low,
the air suspension compressor and valves
may operate repeatedly even though the
vehicle height is not being changed. This
does not indicate a malfunction.
■When “Air Suspension System Malfunc-
tion Visit Your Dealer” is displayed on
the multi-information display
The system may not operate properly. Have
the vehicle inspected by your Lexus dealer.
■Customization
Some functions can be customized.
(  P.476)
Electronically modulated air
suspension*
The height of the vehicle when driv-
ing can be selected using the vehi-
cle height adjustment switch. The
selected height level will be main-
tained regardless of the number of
passengers or weight of cargo.
Additionally, setti ngs of the follow-
ing functions can be changed:
 Enabling/Disabling controls of
access mode
 Temporarily disabling vehicle
height control
WARNING
■Precautions for the electronically
modulated air suspension
●Even if the engine is not running, the
vehicle height may change through
vehicle height control. Be sure to keep
your hands and feet away from the
area underneath the vehicle and
between the tires and vehicle body.
Otherwise part of your body may get
caught, possibly causing an injury.
●In situations such as the following,
make sure to disable all functions of
the vehicle height control of the elec-
tronically modulated air suspension.
Otherwise, the vehicle height may
change and part or your body may be
caught under the vehicle, possibly
causing injury.
• When the vehicle is parked on a curb
• If any of the wheels is not touching the ground

3044-5. Using the driving support systems
■ECB (Electronically Controlled
Brake System) (vehicles with Lexus
Safety System + A)
The electronically controlled system
generates braking force correspond-
ing to the brake operation
■ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the
brakes are applied suddenly, or if the
brakes are applied while driving on a
slippery road surface
■Brake assist
Generates an increased level of brak-
ing force after the brake pedal is
depressed when the system detects a
panic stop situation
■VSC (Vehicle Stability Control)
Helps the driver to control skidding
when swerving sudden ly or turning on
slippery road surfaces.
■TRAC (Traction Control)
Helps to maintain drive power and pre-
vent the drive wheels from spinning when starting the vehicle or accelerat-
ing on slippery roads
■Hill-start assist control
Helps to reduce the backward move-
ment of the vehicle when starting on an
uphill
■VGRS (Variable Gear Ratio Steer-
ing) (if equipped)
Adjusts the front wheel turning angle in
accordance with the vehicle speed and
steering wheel movement
■DRS (Dynamic Rear Steering) (if
equipped)
Contributes to the turning characteris-
tics and responsiveness of the vehicle
by adjusting the rear wheel angle of the
vehicle in accordance with steering
wheel movement.
■EPS (Electric Power Steering)
Employs an electric motor to reduce
the amount of effort needed to turn the
steering wheel.
■Active stabilizer suspension sys-
tem (if equipped)
Reduces sway when cornering accord-
ing to steering wheel movement in
order to maintain a stable vehicle pos-
ture.
■Adaptive Variable Suspension Sys-
tem (if equipped)
By independently controlling the
damping force of th e shock absorbers
for each of the 4 wheels according to
the road and driving conditions, this
system helps riding comfort with supe-
rior vehicle stability, and helps good
Driving assist systems
To keep driving safety and perfor-
mance, the following systems oper-
ate automatically in response to
various driving situations. Be aware,
however, that these systems are
supplementary and should not be
relied upon too heavily when oper-
ating the vehicle.
Summary of the driving assist
systems