2021 LEXUS RX450h Owners Manual

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

2664-5. Using the driving support systems
The Parking Support Brake can be
enabled/disabled on the multi-informa-
tion display. All of the Parking Support
Brake functions (static objects and
rear-crossing vehicles) are
enabled/disabled simultaneously.Use the meter control switches to
enable/disable the parking support
brake. (
P.89)
1 Press or to select .
2 Press or to select
and then press .
When the Parking Support Brake is dis-
abled, the PKSB OFF indicator ( P.78)
illuminates on the multi-information dis-
play.
To re-enable the system when it was dis-
abled, select on the multi-information
display, select and turn it on. If the
system is disabled, it wi ll remain off even if
the power switch is turned to ON mode
after the power switch has been turned off.
If the hybrid system output restriction con-
trol or brake control operates, a buzzer will
sound and a message wi ll be displayed on
the Center Display and multi-information
display, to alert the driver. On vehicles with
a head-up display, the head-up display (if
equipped) will display the same message
as the multi-information display.
Depending on the situat ion, hybrid system
output restriction control will operate to
either limit acceleration or restrict output
as much as possible.
 Hybrid system output restriction
control is operating (acceleration
restriction)
Acceleration greater than a certain
amount is restricted by the system.
Center Display (Panoramic view monitor)
(If equipped): No warning displayed
WARNING
■Limitations of the Parking Support
Brake system
Do not overly rely on the system, as
doing so may lead to an accident.
●The driver is solely responsible for safe
driving. Always drive carefully, taking
care to observe your surroundings.
The Parking Support Brake system is
designed to provide support to lessen
the severity of collis ions. However, it
may not operate in some situations.
●The Parking Support Brake system is
not designed to stop the vehicle com-
pletely. Additionally, even if the system
has stopped the vehicl e, it is necessary
to depress the brake pedal immedi-
ately as brake control will be canceled
after approximately 2 seconds.
NOTICE
■If “Parking Support Brake Unavail-
able” is displayed on the multi-infor-
mation display and the PKSB OFF
indicator is flashing
If this message is displayed immediately
after the power switch is changed to ON
mode, operate the vehicle carefully, pay-
ing attention to your surroundings. It may
be necessary to drive the vehicle for a
certain amount of time before the system
returns to normal. (If the system is not
return to normal after driving for a while,
clean the sensors and their surrounding
area on the bumpers.)
Enabling/Disabling the Parking
Support Brake
Displays and buzzers for hybrid
system output restriction con-
trol and brake control

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

2684-5. Using the driving support systems
Hybrid system output
Braking force
Time
 Figure 2 When hybrid system ou tput restriction control operates
Hybrid system output
Braking force
Time
Hybrid system output restrict ion control begins operating
System determines that po ssibility of collision with detected object is high
Hybrid system output reduced
Example: Multi-informat ion display: “BRAKE!”A
B
C
A
B
C
D
E
F
G

2694-5. Using the driving support systems
4
Driving
Figure 3 When brake control operates
Hybrid system output
Braking force
Time
Hybrid system output restrict ion control begins operating
System determines that po ssibility of collision with detected object is high
Hybrid system output reduced
System determines that possibility of col lision with detected object is extremely
high
Brake control begins operating
Brake control strength increased
Example: Multi-informat ion display: “BRAKE!”
Example: Multi-information display: “Switch to Brake”
■If the Parking Support Brake has oper-
ated
If the vehicle is stopped due to operation of
the Parking Support Brake, the Parking
Support Brake will be disabled and the
PKSB OFF indicator will illuminate. If the
Parking Support Brake operates unneces-
sarily, brake control can be canceled by
depressing the brake pedal or waiting for
approximately 2 seconds for it to automati-
cally be canceled. Then, the vehicle can be
operated by depressing the accelerator
pedal.■Re-enabling the Parking Support Brake
To re-enable the Parking Support Brake
when it has been disabled due to system
operation perform any of the following
operations.
At this time, the PKSB OFF indicator will
turn off. ( P.80)
●Turn the PKSB (Parking Support Brake)
on ( P.266)
●The shift lever is in P.
●Drive with no operation targets in the
traveling direction of the vehicle
A
B
C
D
E
F
G
H
I
J
K

2704-5. Using the driving support systems
●Change the traveling direction of the
vehicle
■If “Parking Support Brake Unavailable”
is displayed on the multi-information
display and the PKSB OFF indicator is
flashing
●If this message is displayed only when the
shift lever is in any position other than R, a
sensor on the front or rear bumper may
be dirty. Clean the sensors and their sur-
rounding area on the bumpers.
●Initialization may no t have been per-
formed after a 12-volt battery terminal
was disconnected and reconnected. Ini-
tialize the system. ( P.270)
If this message continues to be displayed
even after init ialization, have the vehicle
inspected by your Lexus dealer.
■If “Parking Assist Unavailable” and
“Parking Assist Unavailable Clean
Parking Assist Sensor” are displayed on
the multi-informatio n display and the
PKSB OFF indicator is flashing
●A sensor may be covered with ice, snow,
dirt, etc. Remove the ice, snow, dirt, etc.,
from the sensor to return the system to
normal.
If this message is shown even after
removing dirt from the sensor, or shown
when the sensor was not dirty to begin
with, have the vehicle inspected by your
Lexus dealer.
●A sensor may be frozen. Once the ice
melts, the system will return to normal.
●Water may be continuo usly flowing over
the sensor surface, such as in a heavy
rain. When the system determines that it
is normal, the system will return to nor-
mal.
■If a 12-volt battery terminal has been
disconnected and reconnected
The system needs to be initialized. To initial-
ize the system, drive the vehicle straight
ahead for 5 seconds or more at a speed of
approximately 22 mph (35 km/h) or more.
Additionally, for vehicles with the Parking
Support Brake function, turn the steering
wheel fully to the left and right with the vehi-
cle stopped.

2714-5. Using the driving support systems
4
Driving
*:If equipped
This function will operate in situations such as the following if an object is detected
in the traveling direction of the vehicle.
■When traveling at a low speed and the brake pedal is not depressed, or is
depressed late
Parking Support Brake function (static objects)*
If the sensors detect a static object, such as a wall, in the travelling direction of
the vehicle and the system determines that a collision may occur due to the
vehicle suddenly moving forward due to an accidental accelerator pedal oper-
ation, the vehicle moving the unintended direction due to the wrong shift lever
position, or while parking or traveling at low speeds, the system will operate to
lessen the impact with th e detected static object and reduce the resulting
damage.
Examples of function operation

2724-5. Using the driving support systems
■When the accelerator pedal is depressed excessively
■When the vehicle moves in the unintend ed direction due to the wrong shift
lever position
 P.255
Types of sensors
WARNING
■To ensure the Parking Support Brake
can operate properly
Observe the following precautions
regarding the sensors (
P.255). Failure
to do so may cause a sensor to not oper-
ate properly, and may cause an accident.
●Do not modify, disassemble or paint
the sensors.
●Do not replace a sensor with a part
other than a genuine part.
●Do not subject a sensor or its sur-
rounding area to a strong impact.
●Do not damage the sensors, and
always keep them clean.