2021 LEXUS RX350 brake sensor

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

2664-5. Using the driving support systems
*: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 appr oaching and the brake pedal is not
depressed, or is depressed late
 P.238
Parking Support Brake function (rear-crossing vehicles)*
If a rear radar sensor detects a vehicle a pproaching from the right or left at the
rear of the vehicle and the system determ ines that the possibility of a collision
is high, this function will perform brak e 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
function (rear-crossing vehicles) can
operate properly
Observe the following precautions
regarding the rear side radar sensors
(
P.238). 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.

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.

2684-5. Using the driving support systems
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 re ar of the vehicle at a
traveling speed of more than approxi-
mately 15 mph (24 km/h)
*: Depending on the conditions, detection
of a vehicle and/or object may occur.
■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
●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 spla
shed 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

2744-5. Using the driving support systems
■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
■Dynamic Torque Control AWD
system (AWD models)
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.271)
■VDIM (Vehicle Dynamics Inte-
grated Management) (if equipped)
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, engine 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/Trailer Sway
Control systems are operating
The slip indicator light will flash while the
TRAC/VSC/Trailer Sway Control systems
are operating.

2764-5. Using the driving support systems
function has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after
the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■Active Cornering Assist operation
sounds and vibrations
When the Active Cornering Assist is oper-
ated, operation sounds and vibrations may
be generated from the brake system, but
this is not a malfunction.
■EPS operation sound
When the steering wheel is operated, a
motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Reduced effectiveness of the EPS sys-
tem
The effectiveness of the EPS system is
reduced to prevent the system from over-
heating when there is frequent steering
input over an extended period of time. The
steering wheel may feel heavy as a result.
Should this occur, re frain from excessive
steering input or stop the vehicle and turn
the engine off. The EPS system should
return to normal within 10 minutes.
■Automatic reactivation of TRAC, Trailer
Sway Control and VSC systems
After turning the TRAC, Trailer Sway Con-
trol and VSC systems off, the systems will
be automatically re-enabled in the following
situations:
●When the engine switch is turned off
●If only the TRAC system is turned off, the
TRAC will turn on when vehicle speed
increases
If both the TRAC and VSC systems are
turned off, automatic re-enabling will not
occur when vehicle speed increases.
■Operating conditions of Active Corner-
ing Assist
The system operates when the following
occurs.
●TRAC/VSC can operate
●The driver is attempting to accelerate
while turning
●The system detects that the vehicle is
drifting to the outer side
●The brake pedal is released
■Secondary Collision Brake operating
conditions
The system operates when the SRS airbag
sensor detects a collision while the vehicle
is in motion.
However, the system does not operate in
any of the following situations.
●The vehicle speed is below 6 mph (10
km/h)
●Components are damaged
■Secondary Collision Brake automatic
cancellation
The system is automatically canceled in any
of the following situations.
●The vehicle speed drops below approxi-
mately 6 mph (10 km/h)
●A certain amount of time elapses during
operation
●The accelerator pedal is depressed a
large amount
WARNING
■The ABS does not operate effectively
when
●The limits of tire gripping performance
have been exceeded (such as exces-
sively worn tires on a snow covered
road).
●The vehicle hydroplanes while driving
at high speed on wet or slick roads.
■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

4087-2. Steps to take in an emergency
■PKSB OFF indicator (warning buzzer)
■PCS warning light
■Slip indicator
Warning lightDetails/Actions
(flashes)
(if equipped)
When a buzzer sounds:
Indicates a malfunction in the PK SB (Parking Support Brake) system
 Have the vehicle inspected by your Lexus dealer immediately.
When a buzzer does not sound:
Indicates that the system is temporarily unavailable, possibly due to a
sensor being dirty or covered with ice, etc.
 Follow the instructions displayed on the multi-information display.
(  P.260, 412)
Warning lightDetails/Actions
(flashes or illumi-
nates)
When a buzzer sounds simultaneously:
Indicates a malfunction has occurred in the PCS (Pre-Collision System).
 Have the vehicle inspected by your Lexus dealer immediately.
When a buzzer does not sound:
The PCS (Pre-Collision System) has become temporarily unavailable,
corrective action may be necessary.
 Follow the instructions displayed on the multi-information display.
(  P.207, 415)
If the PCS (Pre-Collision System) or VSC (Vehicle Stability Control)
system is disabled, the PCS warning light will illuminate.
 P.215
Warning lightDetails/Actions
When the warning light is illuminated:
Indicates a malfunction in:
The VSC system;
 The TRAC system;
 The Trailer Sway Control; or
 The hill-start assist control system;
 Have the vehicle inspected by your Lexus dealer immediately.
When the warning light flashes:
Indicates that the VSC, TRAC or Tra iler Sway Control system is operat-
ing

4097-2. Steps to take in an emergency
7
When trouble arises
■Parking brake indicator
■Brake hold operated indicator
■Master warning light
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light system monitors the air- bag sensor assembly, fr
ont impact sensors,
side impact sensors (front door), side
impact sensors (rear), driver’s seat position
sensor, driver’s seat belt buckle switch, front
passenger occupant classification system
(ECU and sensors), “AIR BAG ON” indica-
tor light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch,
driver’s seat belt pr etensioner, front passen-
ger’s seat belt pretensioner and force lim-
iter, airbags, interconnecting wiring and
power sources. ( P.30)
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
Warning lightDetails/Actions
(flashes) (U.S.A.)
or
(flashes)
(Canada)
It is possible that the parking brake is not fully engaged or released
 Operate the parking brake switch once again.
This light comes on when the parking brake is not released. If the light
turns off after the parking brake is fu lly released, the system is operating
normally.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
A buzzer sounds and the warning light comes on and flashes to indicate
that the master warning system has detected a malfunction.
P.412