2021 LEXUS RX450h brakes

2584-5. Using the driving support systems
sible.
• There will be a short delay between object detection and display. Even at low
speeds, there is a possibility that the
object will come within the sensor’s
detection areas before the display is
shown and the warning beep sounds.
• It might be difficult to hear the buzzer due to the volume of the audio system or air
flow noise of the air conditioning system.
• It may be difficult to hear the buzzer if buzzers for other systems are sounding.
■Conditions under which the function
may not function correctly
Certain vehicle conditions and the sur-
rounding environment may affect the ability
of a sensor to correctly detect objects. Par-
ticular instances where this may occur are
listed below.
●There is dirt, snow or ice on a sensor.
(Cleaning the sensors will resolve this
problem.)
●A sensor is frozen. (Thawing the area will
resolve this problem.)
In especially cold weather, if a sensor is
frozen the sensor display may be dis-
played abnormally, or objects, such as a
wall, may not be detected.
●A sensor is covered in any way.
●When a sensor or the area around a sen-
sor is extremely hot or cold.
●On an extremely bumpy road, on an
incline, on gravel, or on grass.
●The vicinity of the vehicle is noisy due to
vehicle horns, motorcycle engines, air
brakes of large vehicles, or other loud
noises producing ultrasonic waves.
●There is another vehicle equipped with
parking assist sensors in the vicinity.
●A sensor is coated with a sheet of spray
or heavy rain.
●If a sensor is hit by a large amount of
water, such as when driving on a flooded
road.
●If the vehicle is significantly tilted.
●The vehicle is approaching a tall or
curved curb.
●If objects draw too close to the sensor.
■Objects which may not be properly
detected
The shape of the object may prevent the
sensor from detectin g it. Pay particular
attention to the following objects:
●Wires, fences, ropes, etc.
●Cotton, snow and other materials that
absorb sound waves
●Sharply-angled objects
●Low objects
●Tall objects with upper sections project-
ing outwards in the direction of your vehi-
cle
People may not be de tected if they are
wearing certain types of clothing.
■Detection range of the sensors
Approximately 3.3 ft. (100 cm)
Approximately 4.9 ft. (150 cm)
Approximately 2.0 ft. (60 cm)
The diagram shows the detection range of
the sensors. Note that the sensors cannot
detect objects that are extremely close to
the vehicle.
The range of the sensors may change
depending on the shape of the object, etc.
Sensor detection display, object
distance
A
B
C

2654-5. Using the driving support systems
4
Driving
turned on
• Immediately after the hybrid system is started with the RCTA function on
• When the sensors cannot detect a vehi- cle due to obstructions
●Instances of the RCTA function unneces-
sarily detecting a vehicle and/or object
may increase in the following situations:
• When a vehicle passes by the side of your vehicle
• When the parking space faces a street
and vehicles are being driven on the
street
• 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 a towing eyelet is installed to the
rear of the vehicle
*: If equipped
■Parking Support Brake function
(static objects) (if equipped)
Ultrasonic sensors are used to detect
static objects, such as a wall, in the
detection area when driving at a low
speed or backing up. ( P.271)
■Parking Support Brake function
(rear-crossing vehicles) (if
equipped)
Rear radar sensors are used to detect
approaching vehicles in the detection
area behind the vehicle when backing
up. ( P.277)
PKSB (Parking Support
Brake)*
The Parking Support Brake system
consists of the following functions
that operate when driving at a low
speed or backing up, such as when
parking. When the system deter-
mines that the possibility of a colli-
sion with a detected object is high, a
warning operates to urge the driver
to take evasive action. If the system
determines that the possibility of a
collision with a detected object is
extremely high, the brakes are
automatically applied to help avoid
the collision or help reduce the
impact of the collision.
PKSB (Parking Support Brake)
system

2674-5. Using the driving support systems
4
Driving
Multi-information display: “Object
Detected Acceleration Reduced”
PKSB OFF indicator: Not illuminated
Buzzer: Does not sound
Hybrid system output restriction
control is operating (output
restricted as much as possible)
The system has dete rmined that stron-
ger-than-normal brake operation is neces-
sary.
Center Display (Panoramic view monitor)
(If equipped): “BRAKE!”
Multi-information display: “BRAKE!”
PKSB OFF indicator: Not illuminated
Buzzer: Short beep
 Brake control is operating
The system determined that emergency
braking is necessary. Center Display (Panoramic view monitor)
(If equipped): “BRAKE!”
Multi-information display: “BRAKE!”
PKSB OFF indicator: Not illuminated
Buzzer: Short beep

Vehicle stopped by system opera-
tion
The vehicle has been stopped by brake
control operation.
Center Display (Panoramic view monitor)
(If equipped): “Press Brake Pedal”
Multi-information display: “Switch to
Brake” (If the accelerator pedal is not
depressed, “Press Brake Pedal” will be dis-
played.)
PKSB OFF indicator: Illuminated
Buzzer: Short beep
If the Parking Support Brake determines that a collision with a detected object is
possible, the hybrid system output will be re stricted to restrain any increase in the
vehicle speed. (Hybrid system output restriction control: See figure 2.)
Additionally, if the accelerator pedal contin ues to be depressed, the brakes will be
applied automatically to redu ce the vehicle speed. (Brake control: See figure 3.)
 Figure 1 When the PKSB (Parki ng Support Brake) is disabled
System overview

2754-5. Using the driving support systems
4
Driving
• 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
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 ice, snow, dirt,
etc. (when cleared, the system 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

2834-5. Using the driving support systems
4
Driving
economy through moderate throttle char-
acteristics and by controlling the operation
of the air conditioning system (heat-
ing/cooling).
When not in Eco drive mode, if the driving
mode select switch is turned to the left, the
Eco drive mode indicator will come on.
3Sport mode
Controls the hybrid system to provide
quick, powerful acceleration. This mode
also changes the steering feel, making it
suitable for when agil e driving response is
desired, such as when driving on roads
with many curves.
When not in sport mode, if the driving
mode select switch is turned to the right,
the “Sport” indicator will comes on.
■Operation of the air conditioning sys-
tem in Eco drive mode
Eco drive mode controls the heating/cool-
ing operations and fan speed of the air con-
ditioning system to enhance fuel efficiency.
To improve air condit ioning performance,
adjust the fan speed or turn off Eco drive
mode.
■Automatic deactivation of sport mode
and custom mode
If the power switch is turned off after driving
in sport mode or custom mode, the drive
mode will be changed to normal mode.
■Driving mode pop-up display (12.3-inch
display only)
When the driving mode is changed, the
selected driving mode will be temporarily
displayed on the side display. ( P.300)
■ECB (Electronically Controlled
Brake System)
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
■Enhanced VSC (Enhanced Vehi-
cle Stability Control)
Provides cooperative control of the
ABS, TRAC, VSC and EPS.
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

2844-5. Using the driving support systems
Helps to maintain directional stability
when swerving on slippery road sur-
faces by controlling steering perfor-
mance.
■Trailer Sway Control (if equipped)
Helps the driver to control trailer sway
by selectively applying brake pressure
for individual wheels and reducing
driving torque when trailer sway is
detected.
■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
■Active Cornering Assist (ACA)
Helps to prevent the vehicle from drift-
ing to the outer side by performing
inner wheel brake control when
attempting to accelerate while turning
■Hill-start assist control
Helps to reduce the backward move-
ment of the vehicle when starting on an
uphill
■EPS (Electric Power Steering)
Employs an electric motor to reduce
the amount of effort needed to turn the
steering wheel
■E-Four
Electronic On-Demand AWD system.
Automatically switches from
front-wheel drive to all-wheel drive
(AWD) according to the driving condi-
tions, helping to ensure reliable han-
dling and stability. Examples of
conditions where the system will switch to AWD are when cornering, going
uphill, starting off or accelerating, and
when the road surface is slippery due
to snow, rain, etc.
■Adaptive Variable Suspension Sys-
tem (if equipped)
Controls the damping force of the
shock absorber of each wheel accord-
ing to the road and driving conditions,
helping achieve a comfortable ride,
excellent driveability and a high level of
stability.
If Sport S+ mode is selected using the
driving mode select switch, the damp-
ing force will become more suitable for
sporty driving. ( P.281)
■VDIM (Vehicle Dynamics Inte-
grated Management)
Provides integrated control of the
ABS, brake assist, TRAC, VSC,
hill-start assist control and EPS systems
Helps to maintain vehicle stability when
swerving on slippery road surfaces by
controlling the brakes, hybrid system
output and steering assist.
■The Secondary Collision Brake
When the SRS airbag sensor detects a
collision and the system operates, the
brakes and brake lights are automati-
cally controlled to reduce the vehicle
speed and help reduce the possibility
of further damage due to a secondary
collision.
■When the TRAC/VSC/ABS/Trailer
Sway Control systems are operating
The slip indicator light will flash while the
TRAC/VSC/ABS/Trailer Sway Control
systems are operating.

2874-5. Using the driving support systems
4
Driving
WARNING
■Stopping distance when the ABS is
operating may exceed that of normal
conditions
The ABS is not designed to shorten the
vehicle’s stopping di stance. Always main-
tain a safe distance from the vehicle in
front of you, especially in the following
situations:
●When driving on dirt, gravel or
snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes
or uneven surfaces
■TRAC/VSC may not operate effec-
tively when
Directional control and power may not
be achievable while driving on slippery
road surfaces, even if the TRAC/VSC
system is operating. Drive the vehicle
carefully in conditions where stability and
power may be lost.
■Active Cornering Assist does not
operate effectively when
●Do not overly rely on Active Corner-
ing Assist. Active Cornering Assist
may not operate effectively when
accelerating down slopes or driving on
slippery road surfaces.
●When Active Cornering Assist fre-
quently operates, Active Cornering
Assist may temporarily stop operating
to ensure proper operation of the
brakes, TRAC and VSC.
■Hill-start assist control does not oper-
ate effectively when
●Do not overly rely on hill-start assist
control. Hill-start assist control may
not operate effectively on steep
inclines and roads covered with ice.
●Unlike the parking brake, hill-start
assist control is not intended to hold
the vehicle stationary for an extended
period of time. Do not attempt to use
hill-start assist control to hold the vehi-
cle on an incline, as doing so may lead
to an accident.
■When the TRAC/ABS/VSC/Trailer
Sway Control is activated
The slip indicator light flashes. Always
drive carefully. Reckless driving may
cause an accident. Exercise particular
care when the indicator light flashes.
■When the TRAC/VSC/Trailer Sway
Control systems are turned off
●Be especially careful and drive at a
speed appropriate to the road condi-
tions. As these are the systems to help
ensure vehicle stab ility and driving
force, do not turn the
TRAC/VSC/Trailer Sway Control sys-
tems off unless necessary.
●Trailer Sway Control is part of the VSC
system and will not operate if VSC is
turned off or experiences a malfunc-
tion.
■Replacing tires
Make sure that all ti res are of the speci-
fied size, brand, tread pattern and total
load capacity. In addition, make sure that
the tires are inflated to the recom-
mended tire inflation pressure level.
The ABS, TRAC, Trailer Sway Control
and VSC systems will not function cor-
rectly if different tire s are installed on the
vehicle.
Contact your Lexus dealer for further
information when replacing tires or
wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or
modifying the suspensi on will affect the
driving assist systems, and may cause a
system to malfunction.

2884-5. Using the driving support systems
WARNING
■Trailer Sway Control precaution
The Trailer Sway Control system is not
able to reduce trailer sway in all situa-
tions. Depending on many factors such
as the conditions of the vehicle, trailer,
road surface and driving environment,
the Trailer Sway Control system may not
be effective. Refer to your trailer owner’s
manual for information on how to tow
your trailer properly.
■If trailer sway occurs
Observe the following precautions.
Failing to do so may cause death or seri-
ous injury.
●Firmly grip the steering wheel. Steer
straight ahead. Do not try to control
trailer sway by turning the steering
wheel.
●Begin releasing the accelerator pedal
immediately but very gradually to
reduce speed.
Do not increase speed. Do not apply
vehicle brakes.
If you make no extreme correction with
the steering or brakes, your vehicle and
trailer should stabilize.
■Secondary Collision Brake
Do not rely solely upon the Secondary
Collision Brake. This system is designed
to help reduce the possibility of further
damage due to a secondary collision,
however, that effect changes according
to various conditions. Overly relying on
the system may result in death or serious
injury.