2023 TOYOTA PRIUS PRIME Owners Manual

2975-5. Using the driving support systems
5
Driving
WARNING
●The pre-collision braking func-
tion is not designed to hold the
vehicle stopped. If the vehicle is
stopped by pre-collision brake
control, the driver should oper-
ate the brakes immediately as
necessary.
●The pre-collision braking func-
tion may not operate if certain
operations are performed by the
driver. If the accelerator pedal is
being depressed strongly or the
steering wheel is being turned,
the system may determine that
the driver is taking evasive
action and possibly prevent the
pre-collision braking function
from operating.
●If the brake pedal is being
depressed, the system may
determine that the driver is tak-
ing evasive action and possibly
delay the operation timing of the
pre-collision brake control.
■Acceleration Suppression at
Low Speed
If the steering wheel is being
turned, the syste m may determine
that the driver is taking evasive
action and possibly prevent the
Acceleration Suppression at Low
Speed function from operating or
possibly causing its operation to
be canceled.
■Emergency steering assist
●The emergency steering assist
will be canceled when the sys-
tem determines that lane depar-
ture prevention control has
completed.
●Depending on operations per-
formed by the driver, emer-
gency steering assist may not
operate or operation may be
canceled.
• If the accelerator pedal is depressed strongly, the steering
wheel is turned heavily, the
brake pedal is depressed, or the
turn signal lever is operated, the
system may determine that the
driver is taking evasive action
and the emergency steering
assist may not operate.
• While the emergency steering assist is operating, if the accel-
erator pedal is depressed
strongly, the steering wheel is
turned heavily, or the brake
pedal is depressed, the system
may determine that the driver is
taking evasive action and emer-
gency steering assist operation
may be canceled.
• While the emergency steering assist is operating, if the steer-
ing wheel is held or turned in the
opposite direction of system
operation, emergency steering
assist operation will be can-
celed.

2985-5. Using the driving support systems
■Operating conditions of each function of the pre-collision system
The pre-collision syst em is enabled and the syste m determines that the pos-
sibility of a frontal collision with a detected object is high.
However, the system will not opera te in the following situations:
●When the vehicle has not been driven a certain amount after a terminal of
the 12-volt battery has been disconnected and reconnected
●When the shift position is in R
●When the VSC OFF indica tor is illuminated (only the pre-collision warning
function will be operational)
The following are the operational speeds and cancelation conditions of each
function:
●Pre-collision warning
While the pre-collision warning is operat ing, if the steering wheel is operated
heavily or suddenly, the pre-collision warning may be cancelled.
●Pre-collision brake assist
Detectable objectsVehicle speedRelative speed between
your vehicle and object
Preceding vehicles, stopped vehiclesApproximately 3 to 110 mph (5 to 180 km/h)Approximately 3 to 110 mph (5 to 180 km/h)
Oncoming vehiclesApproximately 20 to 110 mph (30 to 180 km/h)Approximately 50 to 130 mph (80 to 220 km/h)
BicyclesApproximately 3 to 50 mph (5 to 80 km/h)Approximately 3 to 50 mph (5 to 80 km/h)
PedestriansApproximately 3 to 50 mph (5 to 80 km/h)Approximately 3 to 50 mph (5 to 80 km/h)
Preceding motorcycles, stopped motorcyclesApproximately 3 to 110 mph (5 to 180 km/h)Approximately 3 to 50 mph (5 to 80 km/h)
Oncoming motorcyclesApproximately 20 to 110 mph (30 to 180 km/h)Approximately 20 to 110 mph (30 to 180 km/h)
Detectable objectsVehicle speedRelative speed between your vehicle and object
Preceding vehicles, stopped vehiclesApproximately 20 to 110 mph (30 to 180 km/h)Approximately 7 to 110 mph (10 to 180 km/h)
BicyclesApproximately 20 to 50 mph (30 to 80 km/h)Approximately 20 to 50 mph (30 to 80 km/h)

2995-5. Using the driving support systems
5
Driving
●Pre-collision braking
If either of the following occur while th e pre-collision braking function is oper-
ating, it will be canceled:
• The accelerator pedal is strongly depressed
• The steering wheel is operated heavily or suddenly
●Emergency steering assist
The emergency steering assist will not operate when the turn signal lights
are flashing.
PedestriansApproximately 20 to 50 mph (30 to 80 km/h)Approximately 20 to 50 mph (30 to 80 km/h)
Preceding motorcycles, stopped motorcyclesApproximately 20 to 110 mph (30 to 180 km/h)Approximately 7 to 50 mph (10 to 80 km/h)
Detectable objectsVehicle speedRelative speed between your vehicle and object
Preceding vehicles, stopped vehiclesApproximately 3 to 110 mph (5 to 180 km/h)Approximately 3 to 110 mph (5 to 180 km/h)
Oncoming vehiclesApproximately 20 to 110 mph (30 to 180 km/h)Approximately 50 to 130 mph (80 to 220 km/h)
BicyclesApproximately 3 to 50 mph (5 to 80 km/h)Approximately 3 to 50 mph (5 to 80 km/h)
PedestriansApproximately 3 to 50 mph (5 to 80 km/h)Approximately 3 to 50 mph (5 to 80 km/h)
Preceding motorcycles, stopped motorcyclesApproximately 3 to 110 mph (5 to 180 km/h)Approximately 3 to 50 mph (5 to 80 km/h)
Oncoming motorcyclesApproximately 20 to 110 mph (30 to 180 km/h)Approximately 20 to 110 mph (30 to 180 km/h)
Detectable objectsVehicle speedRelative speed between your vehicle and object

3005-5. Using the driving support systems
*: Minimum vehicle speed: Vehicle speed at which evasion using pre-colli-
sion brake control is difficult
While the emergency steering assist is operating, if any of the following are
performed, emergency steering assist operation may be cancelled:
• The accelerator pedal is strongly depressed
• The steering wheel is operated heavily or suddenly
• The brake pedal is depressed
●Intersection collisio n avoidance support (left/right turn)
The intersection collision av oidance support (for left/right turning vehicles)
will not operate when the turn signal lights are not flashing.
●Intersection collisio n avoidance support (crossing vehicles)
Detectable objectsVehicle speedRelative speed between
your vehicle and object
Preceding vehicles,
stopped vehicles, bicy- cles, pedestrians, motorcycles
Approximately 25 to 50 mph (40 to 80 km/h)Approximately 25 to 50 mph (40 to 80 km/h)
Preceding vehicles,
stopped vehicles, bicy- cles, pedestrians, motorcyclesActive steering function
(if equipped):
* to 50
mph (
* to 80 km/h)
Active steering function
(if equipped):
* to 50
mph (
* to 80 km/h)
Detectable objectsVehicle speedOncoming vehicle speedRelative speed between your
vehicle and object
Oncoming vehi- clesApproximately 3 to 25 mph (5 to 40 km/h)Approximately 3 to 45 mph (5 to 75 km/h)Approximately 7
to 70 mph (10 to 115 km/h)
Pedestrians
Approximately 3 to 20 mph (5 to 30 km/h)
-
Approximately 3 to 25 mph (5 to 40 km/h)
Bicycles
Approximately 3 to 20 mph (5 to 30 km/h)
-
Approximately 3 to 30 mph (5 to 50 km/h)
Oncoming motor- cyclesApproximately 3 to 25 mph (5 to 40 km/h)Approximately 3 to 45 mph (5 to 75 km/h)Approximately 7
to 70 mph (10 to 115 km/h)

3015-5. Using the driving support systems
5
Driving
Vehicles without front side radars
Vehicles with front side radars
When driving at approximately 29 m ph (40 km/h) or more, this system will
only operate when the speed of the ot her vehicle is approximately 29 mph
(40 km/h) or less.
The system operates only when the crossing vehicle speed is same as or
less than the vehicle speed.
●Acceleration Suppression at Low Speed
The Acceleration Suppression at Low Speed function will not operate when
the turn signal lights are flashing.
While the Acceleration Suppression at Low Speed function is operating, if
any of the following are performed, the low speed sudden acceleration sup-
pression function operation will be cancelled:
• The accelerator pedal is released.
• The steering wheel is operated heavily or suddenly
■Detection of detectable objects
Objects are detected based on their
size, shape, and movement. Depending on the ambient bright-
ness, movement, posture and direc-
tion of a detectable object, it may
not be detected and the system may
Detectable
objectsVehicle speedCrossing vehicle speedRelative speed between your
vehicle and object
Vehicles, Motor- cycles (side)Approximately 3 to 38 mph (5 to 60 km/h)
• Your vehicle speed or less
• Approximately 25 mph or less
(40 km/h or
less)
Approximately 3 to 38 mph (5 to 60 km/h)
Detectable objectsVehicle speedCrossing vehicle speedRelative speed between your
vehicle and object
Vehicles, Motor- cycles (side)Approximately 3 to 38 mph (5 to 60 km/h)Approximately 31
mph or less (50
km/h or less)Approximately 3 to 38 mph (5 to 60 km/h)
Detectable objectsVehicle speedRelative speed between your vehicle and object
Preceding vehicles, stopped vehicles,
Pedestrians, Bicycles, Wall
Approximately 0 to 9 mph (0 to 15 km/h)Approximately 0 to 9 mph (0 to 15 km/h)

3025-5. Using the driving support systems
not operate properly.
The system detects shapes, such
as the following, as detectable
objects.
■Situations in which the system
may operate even though the
possibility of a collision is not
high
●In certain situations, such as the
following, the system may deter-
mine that the possibility of a colli-
sion is high and operate:
• When passing a detectable object
• When changing lanes while over- taking a detectable object
• When suddenly approaching a detectable object
• When approaching a detectable
object or other object on the road-
side, such as guardrails, utility
poles, trees, walls, etc.
• When there is a detectable object or other object by the roadside at
the entrance of a curve
• When there are patterns or a painting ahead of the vehicle that
may be mistaken for a detectable
object
• When passing a detectable object
that is changing lanes or turning
left/right • When passing a detectable object
which is stopped to make a
left/right turn
• When a detectable object stops immediately before entering the
path of the vehicle
• When passing through a location with a structure above the road
(traffic sign, billboard, etc.)
• When approaching an electric toll gate barrier, parking lot barrier, or
other barrier that opens and
closes
• When turning left/right and an oncoming vehicle, oncoming
motorcycle, pedestrian or bicycle
crosses in front of the vehicle
• When attempting to turn left/right in front of an oncoming vehicle,
oncoming motorcycle, pedestrian
or bicycle
• When turning left/right and an
oncoming vehicle, oncoming
motorcycle, pedestrian or bicycle
stops or changes course immedi-
ately before entering the path of

3035-5. Using the driving support systems
5
Driving
the vehicle
• When turning left/right and an oncoming vehicle turns left/right in
front of the vehicle
• When the steering wheel is oper- ated toward the path of an oncom-
ing vehicle
• When there is an object moving
above or under the road
■Situations in which the system
may not operate properly
●In certain situations, such as the
following, a detectable object may
not be detected by the front sen-
sors, and the system may not
operate properly:
• When a detectable object is approaching your vehicle
• When your vehicle or a detectable object is wandering
• When a detectable object makes
an abrupt maneuver (such as sud-
den swerving, acceleration or
deceleration)
• When suddenly approaching a detectable object
• When the detectable object is
near a wall, fence, guardrail, man-
hole cover, steel plate on the road
surface, or another vehicle
• When there is a structure above a
detectable object
• When part of a detectable object is hidden by another object (large luggage, umbrella, guardrail, etc.)
• When multiple detectable objects are overlapping
• When a bright light, such as the sun, is reflecting off of a detect-
able object
• When a detectable object is white and looks extremely bright
• When the color or brightness of a
detectable object causes it to
blend in with its surroundings
• When a detectable object cuts in
front of or suddenly emerges in
front of your vehicle
• When approaching a vehicle
which is diagonal
• If a bicycle is a child sized bicycle, is carrying a large load, is carrying
an extra passenger, is carrying a
forward leaning rider, or has an
unusual shape (bicycles equipped
with a child seat, tandem bicycles,
etc.)
• If a pedestrian or bicycle is shorter
than approximately 3.2 ft. (1 m) or
taller than approximately 6.5 ft. (2
m).
• When the silhouette of a pedes- trian or bicycle is unclear (such as
when they are wearing a raincoat,
long skirt, etc.)
• When a pedestrian is bending for- ward or squatting
• When a pedestrian or bicycle is moving at high speed
• When a pedestrian is pushing a
stroller, wheelchair, bicycle or
other vehicle
• When a detectable object blends
in with the surrounding area, such
as when it is dim (at dawn or dusk)
or dark (at night or in a tunnel)
• When the vehicle has not been driven for a certain amount of time
after the hybrid system was
started
• While turning left/right or a few seconds after turning left/right
• While driving around a curve and
a few seconds after driving around
a curve
• When turning left/right and an
oncoming vehicle is driving in a
lane 3 or more lanes from the

3045-5. Using the driving support systems
vehicle
• When turning left/right and the direction of the vehicle differs
greatly from the direction traffic
flows in the oncoming lane
• When turning left/right, a pedes- trian or bicycle behind the vehicle
comes in front of it as if it over-
takes the vehicle
• When at an intersection, the approaching crossing vehicle is
long in overall le ngth, such as a
large truck, towing trailer, etc.
●In addition to the preceding, in
certain situations, such as the fol-
lowing, the emergency steering
assist may not operate properly:
• When a detectable object is too
close to the vehicle
• When there is insufficient space to perform evasive steering maneu-
vers or an obstruction exists in the
evasion direction
• When there is an oncoming vehi-
cle
●In addition to the preceding, in
certain situations, such as the fol-
lowing, walls may not be detected
as a target object and the Acceler-
ation Suppression at Low Speed
function may not operate properly:
• When scenery behind the wall is visible, such as a glass door, grid
fence, etc. • When the wall is slanted or low
• When the wall is narrow, such as
a pole, etc.
• When the wall is made of plants, such as a hedge, etc.
• When the road, etc. is reflected on
the wall
• When the vehicle is approaching the wall at an angle
 The pre-collision system can
be enabled/disabled through
a customize setting.
( P.626)
The system is enabled each time
the power switch is turned to ON.
When the system is disabled,
the PCS warning light will illu-
minate and a message will be
displayed on the multi-infor-
mation display.
 The pre-collision setting can
be changed on the customize
settings. ( P.626)
 Vehicles without active steer-
ing function: When the pre-
collision warning timing is
changed, the emergency
steering assist timing will also
be changed.
When later is selected, the
emergency steering assist will
not operate in most cases.
 Vehicles with active steering
function: When the pre-colli-
sion warning timing is
changed, the emergency
steering assist (excluding the
Changing the pre-colli-
sion setting