2019 LEXUS UX250H Owners Manual

2414-5. Using the driving support systems
4
Driving
The buzzer can alert the driver of
faster vehicles approaching from far-
ther away.
Example:
■The RCTA function is operational when
The RCTA function operates when all of the
following conditions are met:
●The power switch is in ON.
●The RCTA function is on.
●The shift lever is in R.
●The vehicle speed is less than approxi-
mately 5 mph (8 km/h).
●The approaching vehicle speed is
between approximately 5 mph (8 km/h)
and 18 mph (28 km/h).
■Setting the buzzer volume
The buzzer volume can be adjusted on the
multi-information display. ( P.231)
■Conditions under which the RCTA func-
tion will not detect a vehicle
The RCTA function 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
●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*
*
: Depending on the conditions, detection of a vehicle and/or object may occur.
■Conditions under which the RCTA func-
tion may not function correctly
●The RCTA function may not detect vehi-
cles correctly in the following situations:
• When a sensor is misaligned due to a
strong impact to the sensor or its sur-
rounding area
• When mud, snow, ice, a sticker, etc. is
covering a sensor or its surrounding area
on the rear bumper
• When driving on a road surface that is
wet with standing water during bad
weather, such as heavy rain, snow, or fog
• When multiple vehicles are approaching
with only a small gap between each vehi-
cle
• If a vehicle is approaching the rear of
your vehicle rapidly
• When a towing eyelet is installed to the rear of the vehicle.
• When backing up on a slope with a sharp
change in grade
Approaching vehi-
cle speed Approximate
alert distance
18 mph (28 km/h) (fast)65 ft. (20 m)
5 mph (8 km/h) (slow)18 ft. (5.5 m)
A

2424-5. Using the driving support systems
• When backing out of a shallow angle parking spot
• Immediately after the RCTA function is 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
●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

2434-5. Using the driving support systems
4
Driving
●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*: If equipped
■Parking Support Brake function
(static objects)
 P.247
■Parking Support Brake function
(rear-crossing vehicles)
 P.252
PKSB (Parking Support
B
rake)*
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.

2444-5. 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/dis-
abled simultaneously.
Use the meter control switches to
enable/disable the parking support
brake. (P.87)
1
Press or to select .
2
Press or to select and
then press “OK”.
When the Parking Support Brake is dis- abled, the PKSB OFF indicator (
P.76)
illuminates on the multi-information dis-
play.
When the Parking Support Brake is turned
on or off, operation of the Parking Support
Brake continues in the same condition the
next time the hybrid system is started.
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
head-up display, the head-up display 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.
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 determined that stronger-
than-normal brake operation is necessary.
Multi-information display: “BRAKE!”
PKSB OFF indicator: Not illuminated
Buzzer: Short beep
WARNING
●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 power switch is changed to ON,
operate the vehicle carefully, paying
attention to your surroundings.
Enabling/Disabling the Parking
Support Brake
Displays and buzzers for hybrid
system output restriction con-
trol and brake control

2454-5. Using the driving support systems
4
Driving
Brake control is operating
The system determined that emergency
braking is necessary.
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.
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 deter-
mines that a collision with a detected
object is possible, the hybrid system
output will be restricted to restrain any
increase in the vehicle speed. (Hybrid
system output restriction control: See
figure 2 below.)
Additionally, if the accelerator pedal
continues to be depressed, the brakes
will be applied automatically to reduce
the vehicle speed. (Brake control: See
figure 3 below.)
Figure 1 When the PKSB (Parking
Support Brake) is disabled Hybrid system output
Braking force
Time
 Figure 2 When hybrid system out-
put restriction control operates
Hybrid system output
Braking force
Time
Hybrid system output restriction
control begins operating (The sys-
tem determines that possibility of
collision with detected object is
high)
“BRAKE!” is displayed on the multi-infor-
mation display.
Hybrid system output reduced
 Figure 3 When brake control oper-
ates
System overview
A
B
C
A
B
C
D
E

2464-5. Using the driving support systems
Hybrid system output
Braking force
Time
Hybrid system output restriction
control begins operating (The sys-
tem determines that possibility of
collision with detected object is
high)
“BRAKE!” is displayed on the multi-infor-
mation display.
Hybrid system output reduced
Brake control begins operating (the
system determines that possibility
of collision with detected object is
extremely high)
Brake control strength increased
“Switch to Brake” is displayed on
the multi-information display
■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 is disabled due to operation of the
Parking Support Brake, either enable the
system again ( P.244), or turn the power
switch off and then back to ON. Addition-
ally, if the object becomes no longer in the
traveling direction of the vehicle or if the
traveling direction of the vehicle changes
(such as changing from moving forward to
backing up, or from backing up to moving
forward), the system will be re-enabled
automatically.
■If “Parking Support Brake Unavailable”
is displayed on th e multi-information
display and the PKSB OFF indicator is
flashing
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.
●A sensor may be cove red with ice, snow,
dirt, etc. Remove the ice, snow, dirt, etc.,
from the sensor to return the system to
normal.
Also, due to ice forming on a sensor at
low temperatures, a warning message
may be displayed or the sensor may not
be able to detect an object. Once the ice
melts, the system wi ll return to normal.
●The surrounding area of the sensors on
the bumper may be dirty, or a sensor may
be covered with ice, snow, dirt, etc. In this
case, remove the ice, snow, dirt, etc. from
the sensor or its surrounding area on the
bumper to return the system to a normal
state. At a low temperature, a warning
message may be displayed or an object
may not be detected due to freezing of
the sensor. Once the ice melts, the sys-
tem will return to normal.
●If this message continues to be displayed
even after cleaning the sensor, or is dis-
played even though the sensor is clean,
have the vehicle inspected by your Lexus
dealer.
●Initialization may not have been per-
formed after a 12-volt battery terminal
was disconnected and reconnected. Ini-
tialize the system. ( P.247)
A
B
C
D
E
F
G
H

2474-5. Using the driving support systems
4
Driving
If this message continues to be displayed
even after initialization, have the vehicle
inspected by your Lexus dealer.
■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.*: If equipped
This function will operate in situations
such as the following if an object is
detected in the traveling direction of
the vehicle.
Parking Support Brake func-
tion (static objects)*
If the sensors detect a static object,
such as a wall, in the traveling direc-
tion of the vehi cle and the system
determines that a collision may
occur due to the vehicle suddenly
moving forward due to an acciden-
tal accelerator pedal operation, the
vehicle moving the unintended
direction due to the wrong shift
position being selected, or while
parking or traveling at low speeds,
the system will operate to lessen
the impact with the detected static
object and reduce the resulting
damage.
Examples of function operation

2484-5. Using the driving support systems
■When traveling at a low speed and
the brake pedal is not depressed,
or is depressed late
■When the accelerator pedal is
depressed excessively
■When the vehicle moves in the
unintended direction due to the
wrong shift position being selected
 P.232
Types of sensors
WARNING
■To ensure the Parking Support Brake
(static objects) can operate properly
Observe the following precautions
regarding the sensors ( P.232). 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.
●If the area around a radar sensor is
subjected to an impact, the system
may not operate properly due to a
sensor malfunction. Have the vehicle
inspected by your Lexus dealer.