2021 TOYOTA PRIUS Owners Manual (in English)

PRIUS_OM_OM47E09U_(U)
3774-5. Using the driving support systems
4
Driving
Accelerator pedal
Brake pedal
Hybrid system output
Braking force Control starts
Collision is
possible
Collision is likely1
2
3
4
5
6
7

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PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
■Operation starting conditions
When the PKSB OFF indicator is not illuminated or flashing ( P. 3 8 3 ,
603) and all of the following conditions are met, the system op erates.
Hybrid system output restriction control
● The Parking Support Brake function is on.
● The vehicle speed is 10 mph (15 km/h) or less.
● There is an obstacle in the traveling direction of the vehicle (6 to
13 ft. [2 to 4 m ahead]).
● The system determined that a stronger-than-normal brake opera-
tion was necessary to avoid a collision.
Brake control
● Hybrid system output restricti on control is being performed.
● The system determined that a n emergency brake operation was
necessary to av oid a collision.
■Operation ending conditions
In any of the following situatio ns, the system stops operating.
Hybrid system output restriction control
● The Parking Support Brake function has been turned off
(stopped).
● The collision became a voidable with normal brake operation.
● The obstacle is no longer in the traveling direction of the veh icle
(6 to 13 ft. [2 to 4 m 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 veh icle
(6 to 13 ft. [2 to 4 m ahead]).
Operation conditions

PRIUS_OM_OM47E09U_(U)
3794-5. Using the driving support systems
4
Driving
When the hybrid system output restriction control or brake cont rol
operates, the buzzer sounds and a message is displayed on the m ulti-
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
ControlSituationMulti-information displayPKSB OFF
Indicator
Buzzer
Hybrid sys-
tem output
restriction
control is
operating
(accelera-
tion limita-
tion control)
Acceleration
at a certain
speed or
higher is not
possible.
Not illumi- nated
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 neces-
sary
Not illumi- nated
Brake con-
trol is operat-
ingEmergency
braking is
necessary
The vehicle
is stopped by
system oper-
ationThe vehicle
is stopped
after brake
control oper-
ation
Illumi-nated

380
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
■Sensor detection range
The detection range of the Parking Support Brake function diffe rs from the
detection range of the intuitive parking assist. ( P. 366)
Therefore, even if the intuitive parking assist detects an obst acle and pro-
vides a warning, the Parking Support Brake function may not sta rt operating.
■ 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 op eration
and you would like to resume operation, either turn the Parking Support
Brake function on again ( P. 375), or turn the power switch off and then back
on. Furthermore, when the vehicle moves with an obstacle no lon ger in the
traveling direction of the vehicle, or when the traveling direc tion 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 rig ht 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
■ Intuitive parking assist buzzer
Regardless of whether the intuitive parking assist is on or off ( P. 362), if the
Parking Support Brake function is not stopped ( P. 375), when the front or
rear sensors detect an obstacle and brake control is performed, the intuitive
parking assist buzzer also sounds and a notification of the app roximate dis-
tance to the obstacle is provided.

PRIUS_OM_OM47E09U_(U)
3814-5. Using the driving support systems
4
Driving
■Situations when the system may operate even though there is no possi-
bility of a collision
In the following situations, the system may operate even though there is no
possibility of a collision.
● Environmental influence
• The vehicle is driven toward a banner or flag, a low-hanging branch or a
boom barrier (such as those used at railroad crossings, toll gates and
parking lots).
• There is an obstacle on the shoulder of the road (when the veh icle is
driven in a narrow tunnel, on a narrow bridge or on a narrow road)
• The vehicle is being parallel parked
• There is a rut or hole in the surface of the road
• When the vehicle is driven on a metal cover (grating), such as those used
for drainage ditches
• The vehicle is driven on a steep slope
• The sensor is covered by water on a flooded road
● Influence from the weather
• Ice, snow, dirt, etc., has adhered to the sensor (if removed, the system
returns to normal)
• Heavy rain or water strikes the vehicle
• In severe weather such as fog, snow or a sand storm
● Influence from other sonic waves
• An ultrasonic wave source is nearby, such as the horn or parki ng assist
sensors of another vehicle, a vehicle detector, a motorcycle en gine or the
air brake of a large vehicle
• Electronic components (such as a backlit license plate (especially fluo-
rescent types), fog lights, a fender pole or a wireless antenna ) are
installed near the sensors
• The vehicle is driven on a narrow
road
• The vehicle is driven on a gravel road or in an area with tall grass

382
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
●Changes in the vehicle
• The vehicle is tilted a large amount
• The height of the vehicle has drastically changed due to the c arried load
(the nose tilts up or down)
• The direction of the sensor has deviated due to a collision or other impact
■ In the unlikely event that the Parking Support Brake function m istakenly
operates at a crossing or elsewhere
Even in the unlikely event that the Parking Support Brake funct ion 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 i s depressed.
Depressing the accelerator pedal again allows you to proceed forward and
leave the area.
■ Situations in which the syst em may not operate normally
In the following situations, the system may not operate normall y.
● Environmental influence
• There is an obstacle that cannot be detected between the vehic le and
another obstacle that can be detected
• An obstacle such as another vehicle, a motorcycle, a bicycle o r a pedes-
trian cuts in front of the vehicle or jumps out from the side.
● Influence from the weather
• Ice, snow, dirt, etc., has adhered to the sensor (if removed, the system
returns to normal)
• Heavy rain or water strikes the vehicle
• In severe weather such as fog, snow or a sand storm • The area around the sensor is extremely hot or cold
• The wind is strong

PRIUS_OM_OM47E09U_(U)
3834-5. Using the driving support systems
4
Driving
●Influence from other sonic waves
• An ultrasonic wave source is nearby, such as the horn or parki ng assist
sensors of another vehicle, a vehicle detector, a motorcycle en gine or the
air brake of a large vehicle
• Electronic components (such as a backlit license plate (especially fluo- rescent types), fog lights, a fender pole or a wireless antenna ) are
installed near the sensors
● Changes in the vehicle
• When driving with the shift position in N
• The vehicle is tilted a large amount
• The height of the vehicle has drastically changed due to the c arried load
(the nose tilts up or down)
• The direction of the sensor has deviated due to a collision or other impact
■ Parking Support Brake function while the Simple Advanced Parkin g
Guidance System is operating
P. 388
■ When removing and instal ling the 12-volt battery
The system needs to be initialized.
The system can be initialized by driving the vehicle straight a head for 5 sec-
onds or more at a speed of approximately 22 mph (35 km/h) or hi gher.
■ When “PKSB Unavailable” is displayed on the multi-information display
and the PKSB OFF indicator flashes
●Ice, snow, dirt, etc., may have adhered to the sensor. If this occurs, remove
the ice, snow, dirt, etc., from the sensor to return the system to normal.
Also, a warning message may be displayed at low temperatures du e to ice
forming on the sensor, and the sensor may not detect obstacles. Once the
ice melts, the system will return 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 i nspected at
your Toyota dealer.
● System initialization may not have been performed after removal and instal-
lation of the 12-volt battery. Perform system initialization.
■ When “PKSB Malfunction Visit Your Dealer” is displayed on the m ulti-
information display, the PKSB OFF indicator flashes and the buz zer
sounds
The system may not be operating properly. Have the vehicle inspected at
your Toyota dealer.

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PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
WARNING
■For safe use
Do not rely solely upon the system. Relying solely upon the sys tem may
lead to an unexpected accident.
● Driving safely is the sole responsibility of the driver. Pay ca reful attention
to the surrounding conditions in order to ensure safe driving. The Parking
Support Brake function can provide support to lessen the severi ty of colli-
sions. However, it may not operate depending on the situation.
● The Parking Support Brake function is not a system designed to com-
pletely stop the vehicle. Furthermore, even if the Parking Support Brake
function is able to stop the vehicle, brake control is canceled after approxi-
mately 2 seconds, so depress the brake pedal immediately.
■ In order for the system to operate properly
Make sure to observe the following precautions regarding the se nsors
(  P. 375). Failure to observe these precautions may cause the sensors
not to operate properly, and may result in an unexpected accide nt.
● Do not perform work such as modification, disassembly or painti ng
● Only perform replacements using genuine parts
● Do not subject the area around the sensors to any impacts
● Do not damage the sensors, and always keep them clean
■ Handling the suspension
Do not modify the suspension, as changes to the height or incli ne of the
vehicle may prevent the sensors from correctly detecting obstac les, may
cause the system not operate, or may cause the system to operate unnec-
essarily.