wheel TOYOTA PRIUS PRIME 2022 Service Manual

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PRIUS PRIME_OM_OM47E74U_(U)
5-5. Using the driving support systems
LTA (Lane Tracing Assist)
While driving on a road with clear white (yellow) lane lines, t he LTA
system warns the driver if the vehicle may deviate from the cur rent
lane or course
*, and also can slightly operate the steering wheel to
help avoid deviation from the lane or course
*. Also, while the dynamic
radar cruise control with full-s peed range is operating, this s ystem will
operate the steering wheel to ma intain the vehicle’s lane position.
The LTA system recognizes white
(yellow) lane lines or a course
*
using the front camera. Addition-
ally, it detects preceding vehicles
using the front camera and radar.
*: Boundary between asphalt and the side of the road, such as grass, soil,
or a curb
Summary of functions

PRIUS PRIME_OM_OM47E74U_(U)
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Driving
WARNING
■Before using LTA system
● Do not rely solely upon the LTA system. The LTA system does not auto-
matically drive the vehicle or reduce the amount of attention that must be
paid to the area in front of the vehicle. The driver must always assume full
responsibility for driving safely by paying careful attention to the surround-
ing conditions and operating the steering wheel to correct the path of the
vehicle. Also, the driver must take adequate breaks when fatigued, such
as from driving for a long period of time.
● Failure to perform appropriate driving operations and pay careful attention
may lead to an accident, resulting in death or serious injury.
● When not using the LTA system, use the LTA switch to turn the system off.
■ Situations unsuitable for LTA system
In the following situations, use the LTA switch to turn the system off. Failure
to do so may lead to an accident, resulting in death or serious injury.
● Vehicle is driven on a road surface which is slippery due to rainy weather,
fallen snow, freezing, etc.
● Vehicle is driven on a snow-covered road.
● White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.
● Vehicle is driven in a temporary lane or restricted lane due to construction
work.
● Vehicle is driven in a construction zone.
● A spare tire, tire chains, etc. are equipped.
● When the tires have been excessively worn, or when the tire inf lation pres-
sure is low.
● During emergency towing.
■ Preventing LTA system malfunctions and operations performed by
mistake
● Do not modify the headlights or place stickers, etc. on the sur face of the
lights.
● Do not modify the suspension etc. If the suspension etc. needs to be
replaced, contact your Toyota dealer.
● Do not install or place anything on the hood or grille. Also, d o not install a
grille guard (bull bars, kangaroo bar, etc.).
● If your windshield needs repairs, contact your Toyota dealer.

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PRIUS PRIME_OM_OM47E74U_(U)
5-5. Using the driving support systems
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. 400) and the pre-
ceding vehicle is swaying. (Your vehicle may sway accordingly a nd depart
from the lane.)
● When the follow-up cruising display is displayed ( P. 400) 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. 400) and the pre-
ceding vehicle is being driven extremely close to the left/righ t 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. 400) 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.).

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Driving
■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 gra ss, soil, or
a curb
Functions included in LTA system

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PRIUS PRIME_OM_OM47E74U_(U)
5-5. Using the driving support systems
■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 gra ss, 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 disp layed on the
multi-information display to alert
the driver.

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Driving
■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 oper ated for
a fixed amount of time or the steering wheel is not being firml y gripped,
a warning is displayed on the multi-information display and the function
is temporarily canceled.

PRIUS PRIME_OM_OM47E74U_(U)
3995-5. Using the driving support systems
5
Driving
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 wh eel
operation support
When that steering wheel assistanc e of the steering assist function
or lane centering function is operating, the indicator illumina tes and
the operation display on the mul ti-information display is turned on.
Lane departure alert function display
Displayed when the multi-informat ion display is switched to the
driving assist system information screen.
*: Boundary between asphalt and the side of the road, such as gra ss, soil, or
a curb
Indications on combination meter
1
2
3
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.

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PRIUS PRIME_OM_OM47E74U_(U)
5-5. Using the driving support systems
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 i s operating by
monitoring the position of a preceding vehicle.
When the follow-up cruising display is displayed, if the preced ing vehicle
moves, your vehicle may move in the same way. Always pay carefu l atten-
tion to your surroundings and operate the steering wheel as nec essary to
correct the path of the vehicle and ensure safety.
■ 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 32 mph (50 km/h) 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 9.8 ft. (3 m) or more.
• Turn signal lever is not operated.
• Vehicle is not being driven around a sharp curve.
• No system malfunctions are detected. ( P. 404)
*1: The function operates even if the vehicle speed is less than a pproxi-
mately 32 mph (50 km/h) when the lane centering function is ope rating.
*2: Boundary between asphalt and the side of the road, such as gra ss, 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. 220)
• 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, TRAC and PCS are not operating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning is not displayed. ( P. 403)
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PRIUS PRIME_OM_OM47E74U_(U)
4015-5. Using the driving support systems
5
Driving
●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. 220)
• Vehicle speed is approximately 32 mph (50 km/h) or more.
• Width of traffic lane is approximately 9.8 ft. (3 m) or more.
• No system malfunctions are detected. ( P. 404)
● Lane centering function
This function operates when all of the following conditions are met.
• LTA is turned on.
• Setting for (“LTA Steering Assist Mode”) and (“LTA
Center Trace On/Off”) in of the multi-information display are set to
“On”. ( P. 220)
• This function recognizes white (yellow) lane lines or the posi tion of a pre-
ceding vehicle (except when the preceding vehicle is small, such as a
motorcycle).
• The dynamic radar cruise control with full-speed range is oper ating in
vehicle-to-vehicle distance control mode.
• Width of traffic lane is approximately 10 to 13 ft. (3 to 4 m) .
• Turn signal lever is not operated.
• Vehicle is not being driven around a sharp curve.
• No system malfunctions are detected. ( P. 404)
• Vehicle does not accelerate or decelerate by a fixed amount or more.
• Steering wheel is not operated with a steering force level suitable for changing lanes.
• ABS, VSC, TRAC and PCS are not operating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning is not displayed. ( P. 403)
• The vehicle is being driven in the center of a lane.
• Steering assist function is not operating.

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5-5. Using the driving support systems
■Temporary cancelation of functions
●When operation conditions are no longer met, a function may be temporarily
canceled. However, when the operation conditions are met again, operation
of the function is automatically restored. ( P. 400)
● If the operation conditions ( P. 401) are no longer met while the lane cen-
tering function is operating, the buzzer may sound to indicate that the func-
tion has been temporarily canceled.
■ Steering assist function/lane centering function
●Depending on the vehicle speed, lane departure situation, road conditions,
etc., the driver may not feel the function is operating or the function may not
operate at all.
● The steering control of the function is overridden by the drive r’s steering
wheel operation.
● Do not attempt to test the operation of the steering assist fun ction.
■ Lane departure alert function
●The warning buzzer may be difficult to hear due to external noi se, audio
playback, etc.
● If the edge of the course
* is not clear or straight, the lane departure alert
function may not operate.
● Do not attempt to test the operation of the lane departure aler t function.
*: Boundary between asphalt and the side of the road, such as gra ss, soil, or
a curb