Toyota Prius (2023 year). Manual in english - page 23

386

4-5. Using the driving support systems

Approximately 100 cm (3.3 ft.)
Approximately 150 cm (4.9 ft.)
Approximately 60 cm (2.0 ft.)
Approximately 100 cm (3.3 ft.)

• The detection range is shown in

the illustration to the right. How-
ever, the sensor will not detect
the obstacle if it is too close.

• For details regarding obstacle

detection in the side areas. 
(



P. 388)

• The distance at which an obsta-

cle can be detected and whether
it can be detected depends on
the shape and condition of the
obstacle.

The obstacle detection range can be changed. (



P. 670)

Detection range of the sensors

1
2
3
4

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Operation conditions

The power switch is turned on.

●

Front corner sensors:
• Shift position is not in P
• Vehicle speed is approximately 10 km/h (6 mph) or less

●

Front side sensors/rear side sensors:
• Shift position is not in P
• Vehicle speed is approximately 10 km/h (6 mph) or less
• Steering wheel is turned approximately 90



 or more

●

Front center sensors:
• Shift position is not in P or R
• Vehicle speed is approximately 10 km/h (6 mph) or less

●

Rear corner sensors/rear center sensors:
Shift position is in R

■

Toyota parking assist-sensor pop-up display



P. 409

■

Sensor detection information

●

The sensor’s detection areas are limited to the areas around the vehicle’s
bumper.

●

Depending on the shape of the obstacle and other factors, the detection dis-
tance may shorten, or detection may be impossible.

●

Obstacles may not be detected if they are too close to the sensor.

●

There will be a short delay between obstacle detection and display. Even
when traveling at a low speed, if you come too close to an obstacle before
the display and buzzer activate, the display and buzzer may not activate at
all.

●

Thin posts or objects lower than the sensor may not be detected when
approached, even if they have been detected once.

●

It might be difficult to hear beeps due to the volume of audio system or air
flow noise of the air conditioning system.

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4-5. Using the driving support systems

■

Obstacle warning function

When an obstacle in the side areas is within the vehicle course while the
vehicle is moving forward or backward, this function inform the driver by the
display and the buzzer.

■

Obstacle detection in side areas

●

Obstacles in the side areas are detected while driving by scanning the side
areas with the side sensors. Recognized obstacles are retained in memory
for up to approximately 2 minutes.

●

Obstacles may not be detected in the side areas until the scan completes.
After the power switch is turned on, scanning completes after driving the
vehicle for a short period of time.

●

When an obstacle such as another vehicle, pedestrian or animal is detected
by the side sensors, the obstacle may continue to be detected even after it
has left the side sensor detection area.

■

If “Clean Parking Assist Sensor” is displayed on the multi-information
display

A sensor may be dirty or covered with snow or ice. In such cases, if it is
removed from the sensor, the system should return to normal.
Also, due to the sensor being frozen at low temperatures, a malfunction dis-
play may appear or an obstacle may not be detected. If the sensor thaws out,
the system should return to normal.

■

If “Parking Assist Malfunction” is displayed on the multi-information dis-
play

Depending on the malfunction of the sensor, the device may not be working
normally. Have the vehicle inspected by any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.

■

Customization

Settings (e.g. buzzer volume) can be changed.
(Customizable features: 



P. 670)

Obstacle
Calculated vehicle course

1

2

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Objects which the system may not properly detect

The shape of the object may prevent the sensor from detecting it. Pay partic-
ular 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 projecting outwards in the direction of your
vehicle

■

Situations in which the system may not operate properly

Certain vehicle conditions and the surrounding environment may affect the
ability of a sensor to correctly detect objects. Particular instances where this
may occur are listed below.

●

There is dirt, snow, water drops or ice on a sensor. (Cleaning the sensors
will resolve this problem.)

●

A sensor is frozen. (Thawing the area will resolve this problem.) In espe-
cially cold weather, if a sensor is frozen the sensor display may be displayed
abnormally, or objects, such as a wall, may not be detected.

●

On an extremely bumpy road, on an incline, on gravel, or on grass.

●

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

●

A sensor is coated with a sheet of spray or heavy rain.

●

If objects draw too close to the sensor.

●

When a pedestrian is wearing clothing that does not reflect ultrasonic waves
(ex. skirts with gathers or frills).

●

When objects that are not perpendicular to the ground, not perpendicular to
the vehicle traveling direction, uneven, or waving are in the detection range.

●

Strong wind is blowing

●

When driving in inclement weather such as fog, snow or a sandstorm

●

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

●

When a sensor or the area around a
sensor is extremely hot or cold.

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4-5. Using the driving support systems

●

If the orientation of a sensor has been changed due to a collision or other
impact

●

When equipment that may obstruct a sensor is installed, such as a towing
eyelet, bumper protector (an additional trim strip, etc.), bicycle carrier, or
snow plow

●

If the front of the vehicle is raised or lowered due to the carried load

●

If the vehicle cannot be driven in a stable manner, such as when the vehicle
has been in an accident or is malfunctioning

●

When tire chains, a compact spare tire or an emergency tire puncture repair
kit are used.

■

Situations in which the system may operate even if there is no possibil-
ity of a collision

In some situations, such as the following, the system may operate even
though there is no possibility of a collision.

●

When driving toward a banner, flag, low-hanging branch or boom barrier
(such as those used at railroad crossings, toll gates and parking lots)

●

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 up or down a steep slope

●

If a sensor is hit by a large amount of water, such as when driving on a
flooded road

●

There is dirt, snow, water drops or ice on a sensor. (Cleaning the sensors
will resolve this problem.)

●

A sensor is coated with a sheet of spray or heavy rain

●

When driving in inclement weather such as fog, snow or a sandstorm

●

When driving on a narrow road

●

When strong winds are blowing

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4-5. Using the driving support systems

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●

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 the front of the vehicle is raised or lowered due to the carried load

●

If the orientation of a sensor has been changed due to a collision or other
impact

●

Driving close to columns (H-shaped steel beams, etc.) in multi-story parking
garages, construction sites, etc.

●

If the vehicle cannot be driven in a stable manner, such as when the vehicle
has been in an accident or is malfunctioning

●

When tire chains, a compact spare tire or an emergency tire puncture repair
kit are used.

●

On an extremely bumpy road, on an
incline, on gravel, or on grass

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4-5. Using the driving support systems

WARNING

■

Cautions regarding the use of the system

There is a limit to the degree of recognition accuracy and control perfor-
mance that this system can provide, do not overly rely on this system. The
driver is always responsible for paying attention to the vehicle’s surround-
ings and driving safely.

■

To ensure the system can operate properly

Observe the following precautions to avoid an unexpected accident.

●

Do not damage the sensors, and always keep them clean.

●

Do not attach a sticker or install an electronic component, such as a backlit
license plate (especially fluorescent type), fog lights, fender pole or wire-
less antenna near a radar sensor.

●

Do not subject the surrounding area of the sensor to a strong impact. If
subjected to an impact, have the vehicle inspected by any authorized
Toyota retailer or Toyota authorized repairer, or any reliable repairer. If the
front or rear bumper needs to be removed/installed or replaced, contact
any authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.

●

Do not modify, disassemble or paint the sensors.

●

Do not attach a license plate cover.

●

Keep your tires properly inflated.

■

When to disable the function

In the following situations, disable the function as it may operate even
though there is no possibility of a collision.

●

Failing to observe the warnings above.

●

A non-genuine Toyota suspension (lowered suspension, etc.) is installed.

■

Side sensors

In the following situations, the Toyota parking assist-sensor may not operate
normally and may result in an unexpected accident. Drive carefully.

●

Obstacles may not be detected in the side areas until the vehicle is driven
for a short time and a scan of the side areas is completed. (



P. 388)

●

Even after the scan of the side areas is completed, obstacles such as
other vehicles, people or animals that approach from the sides cannot be
detected.

●

Even after the scan of the side areas is completed, obstacles may not be
detected depending on the surrounding situation of the vehicle.
At that time, the side sensor operation displays (



P. 382) temporary turn

off.

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WARNING

■

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 malfunctioning.

●

When using steam to wash the vehicle, do not direct steam too close to
the sensors. The sensors may not function properly if subjected to steam.

NOTICE

■

When using Toyota parking assist-sensor

In the following situations, the system may not function correctly due to a
sensor malfunction etc. Have the vehicle checked by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.

●

Toyota parking assist-sensor operation display flashes, and a beep
sounds when no obstacles are detected.

●

If the area around a sensor collides with something, or is subjected to
strong impact.

●

If the bumper collides with something.

●

If the display shows up and remains on without a beep.

●

If a display error occurs, first check the sensor.
If the error occurs even when there is no ice, snow or mud on the sensor, it
is likely that the sensor is malfunctioning.

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4-5. Using the driving support systems

Parking Support Brake function



The system operates in the following situations when an obstacle is
detected in the traveling direction of the vehicle.

◆

The vehicle is driven at low speeds and the brake pedal is not
depressed, or is depressed too late

◆

The accelerator pedal is depressed too far



: If equipped

When a collision may occur with an obstacle while parking or
traveling at low speeds, when the vehicle suddenly moves for-
ward due to mistaken accelerator pedal operation, or when the
vehicle moves due to the wrong shift position being selected,
the sensors detect obstacles to the front or rear in the traveling
direction of the vehicle, and the system operates to lessen
impact with obstacles such as walls, and reduce resulting dam-
age.

Examples of system operation

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4-5. Using the driving support systems

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◆

The vehicle moves due to the wrong shift position being
selected

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4-5. Using the driving support systems

Front corner sensors
Front center sensors
Rear corner sensors
Rear center sensors

The Parking Support Brake function can be enabled/disabled on the

 screen (



P. 153) of the multi-information display.

When the Parking Support Brake
function is off, the PKSB OFF indi-
cator illuminates.

When the Parking Support Brake function is switched off, system operation

does not resume until the function is switched back on through the 
screen on the multi-information display. (System operation does not
resume by operating the power switch.)

Types of sensors

1
2
3
4

Changing settings of the Parking Support Brake function

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When the Parking Support Brake function detects an obstacle with a
probability of collision, hybrid system output is restricted to restrain an
increase in vehicle speed. (Hybrid system output restriction control: A)
Furthermore, when the accelerator pedal continues to be depressed,
the brakes are applied to reduce the vehicle speed. (Brake control: B)

Operation

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4-5. Using the driving support systems

DOWN

DOWN

UP

ON

OFF

ON

OFF

ON

OFF

Accelerator pedal
Brake pedal
Hybrid system output
Braking force

Control starts
Collision is possible
Collision is likely

1
2
3
4

5
6
7

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Operation starting conditions

When the PKSB OFF indicator is not illuminated or flashing
(



P. 402, 580) and all of the following conditions are met, the

system operates.



Hybrid system output restriction control

●

The Parking Support Brake function is on.

●

The vehicle speed is approximately 15 km/h (10 mph) or less.

●

There is an obstacle in the traveling direction of the vehicle
(approximately 2 to 4 m [6 to 13 ft.] ahead).

●

The system determined that a stronger-than-normal brake opera-
tion was necessary to avoid a collision.



Brake control

●

Hybrid system output restriction control is being performed.

●

The system determined that an emergency brake operation was
necessary to avoid a collision.

■

Operation ending conditions

In any of the following situations, the system stops operating.



Hybrid system output restriction control

●

The Parking Support Brake function has been turned off
(stopped).

●

The collision became avoidable with normal brake operation.

●

The obstacle is no longer in the traveling direction of the vehicle
(approximately 2 to 4 m [6 to 13 ft.] ahead).



Brake control

●

The Parking Support Brake function has been turned off
(stopped).

●

Approximately 2 seconds elapsed after the vehicle was stopped
by brake control.

●

The brake pedal was depressed after the vehicle was stopped by
brake control.

●

The obstacle is no longer in the traveling direction of the vehicle
(approximately 2 to 4 m [6 to 13 ft.] ahead).

Operation conditions

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4-5. Using the driving support systems

When the hybrid system output restriction control or brake control
operates, the buzzer sounds and a message is displayed on the multi-
information display to alert the driver.

Depending on the situation, output restriction control operates to either
limit acceleration or restrict output as much as possible.

Display and buzzer for hybrid system output restriction control
and brake control

Control

Situation

Multi-information 

display

PKSB OFF 

Indicator

Buzzer

Hybrid sys-
tem output
restriction
control is
operating
(accelera-
tion limita-
tion control)

Accelera-
tion at a cer-
tain speed
or higher is
not possible.

Not 

illuminated

Short 

beep

Hybrid sys-
tem output
restriction
control is
operating
(control to
restrict out-
put as much
as possible)

A stronger-
than-normal
brake opera-
tion is nec-
essary

Not 

illuminated

Brake con-
trol is oper-
ating

Emergency
braking is
necessary

The vehicle
is stopped
by system
operation

The vehicle
is stopped
after brake
control oper-
ation

Illuminated

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Sensor detection range

The detection range of the Parking Support Brake function differs from the
detection range of the Toyota parking assist-sensor. (



P. 386)

Therefore, even if the Toyota parking assist-sensor detects an obstacle and
provides a warning, the Parking Support Brake function may not start operat-
ing.

■

System operation

When the vehicle is stopped by system operation, the Parking Support Brake
function stops and the PKSB OFF indicator illuminates.

■

System recovery

When the Parking Support Brake function is stopped by system operation
and you would like to resume operation, either turn the Parking Support
Brake function on again (



P. 396), or turn the power switch off and then back

on. Furthermore, when the vehicle moves with an obstacle no longer in the
traveling direction of the vehicle, or when the traveling direction of the vehicle
changes (such as when switching from moving forward to backing up, and
vice versa), system operation automatically resumes.

■

Obstacles not detected by the sensors

The following obstacles may not be detected by the sensors.

●

Objects such as people, cloth and snow, that are difficult for sonic waves to
reflect off of. (In particular, people may also not be detected depending on
the type of clothing they are wearing.)

●

Objects not perpendicular with the ground, objects not at a right angle to the
traveling direction of the vehicle, uneven objects or waving objects

●

Low objects

●

Thin objects such as wires, fences, ropes and signposts

●

Objects that are extremely close to the bumper

■

Situations in which the system may not operate properly



P. 389

■

Situations in which the system may operate even if there is no possibil-
ity of a collision



P. 390

■

In the unlikely event that the Parking Support Brake function mistakenly
operates at a crossing or elsewhere

Even in the unlikely event that the Parking Support Brake function mistakenly
operates at a crossing or elsewhere, brake control is canceled after approxi-
mately 2 seconds, allowing you to proceed forward and leave the area. Fur-
thermore, brake control is also canceled when the brake pedal is depressed.
Depressing the accelerator pedal again allows you to proceed forward and
leave the area.