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PRIUS_OM_OM47F01U_(U)
3654-5. Using the driving support systems
4
Driving
■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 dir ection of your
vehicle
■ Situations in which the syst em 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 m ay 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 ult rasonic 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 d etection range.
● Strong wind is blowing
● When driving in inclement weather such as fog, snow or a sandst orm
● When an object that cannot be detected is between the vehicle a nd 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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PRIUS_OM_OM47F01U_(U)
3674-5. Using the driving support systems
4
Driving
●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 car ried load
● If the orientation of a sensor has been changed due to a collis ion 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 whe n the vehicle
has been in an accident or is malfunctioning
● When tire chains, a compact spare tire or an emergency tire pun cture repair
kit are used.
●
On an extremely bumpy road, on an
incline, on gravel, or on grass
Page 370 of 744
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4-5. Using the driving support systems
Parking Suppor t Brake function
The system operates in the follo wing situations when an obstacle is
detected in the traveling d irection 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 travel ing
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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Front corner sensors
Front center sensors
Rear corner sensors
Rear center sensors
The Parking Support Brake funct ion can be enabled/disabled on the
screen ( P. 151) 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 Park ing Support Brake function
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PRIUS_OM_OM47F01U_(U)
3734-5. Using the driving support systems
4
Driving
When the Parking Support Brake f unction detects an obstacle with a
probability of collision, hybrid system output is restricted to restrain an
increase in vehicle speed. (Hybri d system output restriction control: A)
Furthermore, when the accelerator pedal continues to be depress ed,
the brakes are applied to reduce the vehicle speed. (Brake control: B)
Operation
DOWN
DOWN
UP
ON
OFF
ON
OFF
ON
OFF
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4-5. Using the driving support systems
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_OM47F01U_(U)
3754-5. Using the driving support systems
4
Driving
■Operation starting conditions
When the PKSB OFF indicator is not illuminated or flashing ( P. 3 7 8 ,
599) 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 approxima tely 10 mph (15 km/h) or less.
● There is an obstacle in the traveling direction of the vehicle
(approximately 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
(approximately 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
(approximately 6 to 13 ft. [2 to 4 m] ahead).
Operation conditions
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4-5. Using the driving support systems
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