2021 LEXUS RX350 engine

2554-5. Using the driving support systems
4
Driving
*: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.261)
■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.267) 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.
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
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 collisions. 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 engine swit ch is changed to
IGNITION ON mode, operate the vehi-
cle carefully, paying attention to your sur-
roundings. 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

2564-5. Using the driving support systems
Use the meter control switches to
enable/disable the parking support
brake. (P.82)
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.72)
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 will remain off even if
the engine switch is turned to IGNITION
ON mode after the engine switch has
been turned off.
If the engine output restriction control or
brake control operates, a buzzer will sound
and a message will be displayed on the
Center Display and multi-information dis-
play, 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 situation, engine output
restriction control will operate to either
limit acceleration or restrict output as
much as possible.
 Engine 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
Multi-information display: “Object Detected Acceleration Reduced”
PKSB OFF indicator: Not illuminated
Buzzer: Does not sound

Engine output restriction control is
operating (output restricted as
much as possible)
The system has determined 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
Displays and buzzers for engine
output restriction control and
brake control

2574-5. Using the driving support systems
4
Driving
If the Parking Support Brake determines that a collision with a detected object is
possible, the engine output will be restricted to restrain any increase in the vehicle
speed. (Engine output restrict ion 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
Engine output
Braking force
Time
 Figure 2 When engine output restriction control operates
Engine output
System overview
A
B
C
A

2584-5. Using the driving support systems
Braking force
Time
Engine output restriction control begins operating
System determines that po ssibility of collision with detected object is high
Engine output reduced
Example: Multi-informat ion display: “BRAKE!”
 Figure 3 When brake control operates
Engine output
Braking force
Time
Engine output restriction control begins operating
System determines that po ssibility of collision with detected object is high
Engine 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-
B
C
D
E
F
G
A
B
C
D
E
F
G
H
I
J
K

2624-5. Using the driving support systems
■The Parking Support Brake function
(static object) will operate when
The function will operate when the PKSB
OFF indicator is not illuminated or flashing
(  P.73, 74) and all of the following condi-
tions are met:
●Engine output restriction control
• The Parking Support Brake is enabled.
• The vehicle speed is 9 mph (15 km/h) or less.
• There is a static object in the traveling direction of the vehicle and 6 to 13 ft. (2
to 4 m) away.
• The Parking Support Brake determines that a stronger-than-normal brake opera-
tion is necessary to avoid a collision.
●Brake control
• Engine output restriction control is oper-
ating.
• The Parking Support Brake determines that an immediate brake operation is nec-
essary to avoid a collision.
■The Parking Support Brake function
(static objects) 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 system determines that the collision has become avoidable with normal brake
operation.
• The static object is no longer 6 to 13 ft. (2
to 4 m) away from the vehicle or in the
WARNING
■Handling the suspension
Do not modify the suspension, as
changes to the height or inclination of the
vehicle may prevent the sensors from
detecting objects correctly or cause the
system to not operate or operate unnec-
essarily.
■If the Parking Support Brake function
(static objects) operates unnecessar-
ily, such as at a railroad crossing
In the event that the Parking Support
Brake function (static objects) operates
unnecessarily, such as at a railroad cross-
ing, brake control w ill be canceled after
approximately 2 seconds, allowing you
to proceed forward and leave the area,
brake control can also be canceled by
depressing the brake pedal. Depressing
the accelerator pedal after brake control
is canceled will allow you to proceed for-
ward and leave the area.
■Notes when washing the vehicle
Do not apply intensive bursts of water or
steam to the sensor area.
Doing so may result in the sensor mal-
functioning.
●When using a high pressure washer to
wash the vehicle, do not spray the sen-
sors directly, as doing so may cause a
sensor to malfunction.
●When using steam to clean the vehicle,
do not direct steam too close to the
sensors as doing so may cause a sen-
sor to malfunction.
■When to disable the Parking Support
Brake
In the following situations, disable the
Parking Support Brake as the system
may operate even though there is no
possibility of a collision.
●When inspecting the vehicle using a
chassis roller, chassis dynamo or free
roller
●When loading the vehicle onto a boat,
truck or other transport vessel
●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
lowered due to the carried load
●When equipment that may obstruct a
sensor is installed, such as a towing
eyelet, bumper protector (an addi-
tional trim strip, etc.), bicycle carrier, or
snow plow
●When using an automatic car wash

2644-5. Using the driving support systems
• 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

2674-5. Using the driving support systems
4
Driving
■The Parking Support Brake function
(rear-crossing vehicles) will operate
when
The function will oper ate when the PKSB
OFF indicator is not illuminated or flashing
(  P.73, 74) and all of the following condi-
tions 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 approaching from the right or left at the re ar of the vehicle at a
traveling speed of less than approxi-
mately 5 mph (8 km/h)
• The shift lever 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
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.259
■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.253). 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
WARNING
●If the area around a rear side radar
sensor is subjected to an impact, the
system may not operate properly due
to a sensor malfunct ion. Have the vehi-
cle inspected by your Lexus dealer.

2704-5. Using the driving support systems
Except F SPORT models
1 Normal mode
Provides an optimal ba lance of fuel econ-
omy, quietness, and dynamic performance.
Suitable for city driving.
Press the switch to change the driving
mode to normal mode when Eco drive
mode or sport mode is selected.
2 Eco drive mode
Helps the driver accelerate in an
eco-friendly manner and improve fuel
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.
3 Sport mode
Controls the transmission and engine to
provide quick, powerful acceleration. This
mode also changes the steering feel, mak-
ing it suitable for when agile 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.
F SPORT models (vehicles with
Adaptive Variable Suspension Sys-
tem)
1 Normal mode/Custom mode
Normal mode and custom mode are
selected by pressing the driving mode
select switch. Each time the switch is
pressed, the driving mode changes
between normal mode and custom mode.
When custom mode is selected, the “Cus-
tom” indicator will be illuminated.
When Eco drive mode or sport mode is
Driving mode select switch
The driving modes can be selected
to suit driving conditions.
Selecting a drive mode