TOYOTA PRIUS PLUG-IN HYBRID 2021 Owners Manual

4315-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
WARNING
■ Conditions in which functions may not operate properly
In the following situations, the functions may not operate properly and the
vehicle may depart from its lane. Drive safely by always paying careful
attention to your surroundings and operate the steering wheel to correct the
path of the vehicle without relying solely on the functions.
● When the follow-up cruising display is displayed (P. 439) and the pre-
ceding vehicle is swaying. (Your vehicle may sway accordingly and depart
from the lane.)
● When the follow-up cruising display is displayed (P. 439) and the pre-
ceding vehicle departs from its lane. (Your vehicle may follow the preced-
ing vehicle and depart from the lane.)
● When the follow-up cruising display is displayed (P. 439) and the pre-
ceding vehicle is being driven extremely close to the left/right lane line.
(Your vehicle may follow the preceding vehicle and depart from the lane.)
● Vehicle is being driven around a sharp curve.
●When the follow-up cruising display is
displayed ( P. 439) and the preceding
vehicle changes lanes. (Your vehicle
may follow the preceding vehicle and
also change lanes.)
●Objects or patterns that could be mis-
taken for white (yellow) lines are pres-
ent on the side of the road (guardrails,
reflective poles, etc.).

4325-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
WARNING
●There are shadows on the road that run parallel with, or cover, the white
(yellow) lines.
● The vehicle is driven in an area without white (yellow) lines, such as in
front of a tollgate or checkpoint, or at an intersection, etc.
● The white (yellow) lines are cracked, “Raised pavement marker” or stones
are present.
● The white (yellow) lines cannot be seen or are difficult to see due to sand,
etc.
● The vehicle is driven on a road surface that is wet due to rain, puddles,
etc.
● The traffic lines are yellow (which may be more difficult to recognize than
lines that are white).
● The white (yellow) lines cross over a curb, etc.
● The vehicle is driven on a bright surface, such as concrete.
● If the edge of the road is not clear or straight.
● The vehicle is driven on a surface that is bright due to reflected light, etc.
●Vehicle is driven where the road
diverges, merges, etc.
● Repair marks of asphalt, white (yellow)
lines, etc. are present due to road
repair.

4335-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
WARNING
● The vehicle is driven in an area where the brightness changes suddenly,
such as at the entrances and exits of tunnels, etc.
● Light from the headlights of an oncoming vehicle, the sun, etc. enters the
camera.
● The vehicle is driven on a slope.
● The vehicle is driven on a road which tilts left or right, or a winding road.
● The vehicle is driven on an unpaved or rough road.
● The traffic lane is excessively narrow or wide.
● The vehicle is extremely tilted due to carrying heavy luggage or having
improper tire pressure.
● The distance to the preceding vehicle is extremely short.
● The vehicle is moving up and down a large amount due to road conditions
during driving (poor roads or road seams).
● When driving in a tunnel or at night with the headlights off or when a head-
light is dim due to its lens being dirty or it being misaligned.
● The vehicle is struck by a crosswind.
● The vehicle is affected by wind from a vehicle driven in a nearby lane.
● The vehicle has just changed lanes or crossed an intersection.
● Tires which differ by structure, manufacturer, brand or tread pattern are
used.
● When tires of a size other than specified are installed.
● Snow tires, etc. are equipped.
● The vehicle is being driven at extremely high speeds.

4345-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Lane departure alert function
When the system determines
that the vehicle might depart
from its lane or course
*, a
warning is displayed on the
multi-information display, and a
warning buzzer will sound to
alert the driver.
When the warning buzzer
sounds, check the area around
your vehicle and carefully oper-
ate the steering wheel to move
the vehicle back to the center of
the lane.
*: Boundary between asphalt and the side of the road, such as grass, soil, or
a curb
Functions included in LTA system

4355-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
■Steering assist function
When the system determines
that the vehicle might depart
from its lane or course
*, the
system provides assistance as
necessary by operating the
steering wheel in small
amounts for a short period of
time to keep the vehicle in its
lane.
If the system detects that the
steering wheel has not been
operated for a fixed amount of
time or the steering wheel is not
being firmly gripped, a warning
is displayed on the multi-infor-
mation display and the function
is temporarily canceled.
*: Boundary between asphalt and the side of the road, such as grass, soil, or
a curb
■
Vehicle sway warning function
When the vehicle is swaying
within a lane, the warning
buzzer will sound and a mes-
sage will be displayed on the
multi-information display to alert
the driver.

4365-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Lane centering function
This function is linked with
dynamic radar cruise control
with full-speed range and pro-
vides the required assistance
by operating the steering wheel
to keep the vehicle in its current
lane.
When dynamic radar cruise con-
trol with full-speed range is not
operating, the lane centering
function does not operate.
In situations where the white
(yellow) lane lines are difficult to
see or are not visible, such as
when in a traffic jam, this func-
tion will operate to help follow a
preceding vehicle by monitoring
the position of the preceding
vehicle.
If the system detects that the steering wheel has not been operated for
a fixed amount of time or the steering wheel is not being firmly gripped,
a warning is displayed on the multi-information display and the function
is temporarily canceled.

4375-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
Press the LTA switch to turn the
LTA system on.
The LTA indicator illuminates and a
message is displayed on the multi-
information display.
Press the LTA switch again to turn
the LTA system off.
When the LTA system is turned on
or off, operation of the LTA system
continues in the same condition
the next time the hybrid system is
started.
Tu r n i n g LTA s y s t e m o n

4385-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
LTA i n d i c a t o r
The illumination condition of the
indicator informs the driver of
the system operation status.
Illuminated in green: LTA sys-
tem is operating.
Flashing in orange: Lane
departure alert function is oper-
ating.
Steering control indicator and operation display of steering wheel
operation support
When that steering wheel assistance of the steering assist function
or lane centering function is operating, the indicator illuminates and
the operation display on the multi-information display is turned on.
Lane departure alert function display
Displayed when the multi-information display is switched to the
driving assist system information screen.
Indications on combination meter
1
2
3

4395-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
*: Boundary between asphalt and the side of the road, such as grass, soil, or
a curb
Follow-up cruising display
Displayed when the multi-information display is switched to the driving
assist system information screen.
Indicates that steering assist of the lane centering function is operating by
monitoring the position of a preceding vehicle.
When the follow-up cruising display is displayed, if the preceding vehicle
moves, your vehicle may move in the same way. Always pay careful atten-
tion to your surroundings and operate the steering wheel as necessary to
correct the path of the vehicle and ensure safety.
Inside of displayed lines is
whiteInside of displayed lines is
black
Indicates that the system is recog-
nizing white (yellow) lines or a
course
*. When the vehicle
departs from its lane, the white
line displayed on the side the
vehicle departs from flashes
orange.Indicates that the system is not
able to recognize white (yellow)
lines or a course* or is temporar-
ily canceled.
4

4405-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Operation conditions of each function
●Lane departure alert function
This function operates when all of the following conditions are met.
• LTA is turned on.
• Vehicle speed is approximately 50 km/h (32 mph) or more.
*1
• System recognizes white (yellow) lane lines or a course*2. (When a white
[yellow] line or course
*2 is recognized on only one side, the system will
operate only for the recognized side.)
• Width of traffic lane is approximately 3 m (9.8 ft.) or more.
• Turn signal lever is not operated.
• Vehicle is not being driven around a sharp curve.
• No system malfunctions are detected. (P. 444)
*1: The function operates even if the vehicle speed is less than approxi-
mately 50 km/h (32 mph) when the lane centering function is operating.
*2: Boundary between asphalt and the side of the road, such as grass, soil,
or a curb
●Steering assist function
This function operates when all of the following conditions are met in addi-
tion to the operation conditions for the lane departure alert function.
• Setting for (“LTA Steering Assist Mode”) in of the multi-
information display is set to “On”. (P. 230)
• Vehicle is not accelerated or decelerated by a fixed amount or more.
• Steering wheel is not operated with a steering force level suitable for
changing lanes.
• ABS, VSC, TRC and PCS are not operating.
• TRC or VSC is not turned off.
• Hands off steering wheel warning is not displayed. (P. 443)
●Vehicle sway warning function
This function operates when all of the following conditions are met.
• Setting for (“Lane Sway Warning Status”) in of the multi-
information display is set to “On”. (P. 230)
• Vehicle speed is approximately 50 km/h (32 mph) or more.
• Width of traffic lane is approximately 3 m (9.8 ft.) or more.
• No system malfunctions are detected. (P. 444)