TOYOTA PRIUS PRIME 2020 Owners Manual (in English)

PRIUS PRIME_OM_OM47C77U_(U)
3915-5. Using the driving support systems
5
Driving
●In some situations such as the following, sufficient braking fo rce may not be
obtained, preventing the system from performing properly:
• If the braking functions cannot operate to their full extent, such as when
the brake parts are extremely cold, extremely hot, or wet
• If the vehicle is not properly maintained (brakes or tires are excessively
worn, improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other sli ppery sur-
face
● Some pedestrians such as the following may not be detected by t he radar
sensor and camera sensor, preventing the system from operating properly:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or taller than approx-
imately 6.5 ft. (2 m)
• Pedestrians wearing oversized clothing (a rain coat, long skir t, etc.), mak-
ing their silhouette obscure
• Pedestrians who are carrying large baggage, holding an umbrella, etc., hiding part of their body
• Pedestrians who are bending forward or squatting
• Pedestrians who are pushing a stroller, wheelchair, bicycle or other vehi-
cle
• Groups of pedestrians which are close together
• Pedestrians who are wearing white and look extremely bright
• Pedestrians in the dark, such as at night or while in a tunnel
• Pedestrians whose clothing appears to be nearly the same color or
brightness as their surroundings
• Pedestrians near walls, fences, guardrails, or large objects
• Pedestrians who are on a metal object (manhole cover, steel plate, etc.)
on the road
• Pedestrians who are walking fast
• Pedestrians who are changing speed abruptly
• Pedestrians running out from behind a vehicle or a large objec t
• Pedestrians who are extremely close to the side of the vehicle (outside
rear view mirror, etc.)

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PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
■If the PCS warning light flashes or illuminates and a warning m essage is
displayed on the multi-information display
The pre-collision system may be temporarily unavailable or ther e may be a
malfunction in the system.
● In the following situations, the warning light will turn off, t he message will
disappear and the system will become operational when normal op erating
conditions return:
• When the radar sensor or camera sensor or the area around eith er sen-
sor is hot, such as in the sun
• When the radar sensor or camera sensor or the area around eith er sen-
sor is cold, such as in an extremely cold environment
• When a front sensor is dirty or covered with snow, etc.
• When the part of the windshield in front of the camera sensor is fogged
up or covered with condensation or ice
(Defogging the windshield: P. 504, 514)
• If the camera sensor is obstructed, such as when the hood is open or a sticker is attached to the windshield near the camera sensor
● If the PCS warning light continues to flash or remains illuminated or the
warning message does not disappear even though the vehicle has returned
to normal, the system may be malfunctioning. Have the vehicle inspected by
your Toyota dealer immediately.
■ If VSC is disabled
●If VSC is disabled ( P. 491), the pre-collision brake assist and pre-collision
braking functions are also disabled.
● The PCS warning light will turn on and “VSC Turned Off Pre-Coll ision Brake
System Unavailable” will be displayed on the multi-information display.

393
PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
5
Driving
LDA (Lane Depar ture Al ert with steering
control)
When driving on highways and freeways with white (yellow) lines , this
function alerts the driver when the vehicle might depart from i ts lane
and provides assistance by opera ting the steering wheel to keep the
vehicle in its lane.
The LDA system recognizes visi-
ble white (yellow) lines with the
camera sensor on the upper por-
tion of the front windshield.
◆Lane departure alert function
When the system determines
that the vehicle might depart
from its lane, a warning is dis-
played on the multi-information
display and the warning buzzer
sounds to alert the driver.
When the warning buzzer
sounds, check the surrounding
road situation and carefully
operate the steering wheel to
move the vehicle back to the
center of the lane.
Summary of functions
Functions included in LDA system

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PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
◆Steering control function
When the system determines
that the vehicle might depart
from its lane, the system pro-
vides assistance as necessary
by operating the steering wheel
in small amounts for a short
period of time to keep the vehi-
cle 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 warning
buzzer sounds.
◆Vehicle sway warning function
When the vehicle is swaying or
appears as if it may depart from
its lane multiple times, the
warning buzzer sounds and a
message is displayed on the
multi-information display to alert
the driver.

PRIUS PRIME_OM_OM47C77U_(U)
3955-5. Using the driving support systems
5
Driving
WARNING
■Before using LDA system
Do not rely solely upon the LDA system. The LDA 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 fatigu ed, 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.
■ To avoid operating LDA system by mistake
When not using the LDA system, use the LDA switch to turn the system off.
■ Situations unsuitable for LDA system
Do not use the LDA system in the following situations.
The system may not operate properly and lead to an accident, re sulting in
death or serious injury.
● 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.
● Tires which differ by structure, manufacturer, brand or tread p attern are
used.
● Objects or patterns that could be mistaken for white (yellow) l ines are
present on the side of the road (guardrails, curbs, reflective poles, etc.).
● Vehicle is driven on a snow-covered road.
● White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.
● Asphalt repair marks, white (yellow) line marks, etc. are prese nt due to
road repair.
● Vehicle is driven in a temporary lane or restricted lane due to construction
work.
● Vehicle is driven on a road surface which is slippery due to rainy weather,
fallen snow, freezing, etc.
● Vehicle is driven in traffic lanes other than on highways and freeways.
● Vehicle is driven in a construction zone.

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PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
Press the LDA switch to turn the
LDA system on.
The LDA indicator illuminates and
a message is displayed on the
multi-information display.
Press the LDA switch again to turn
the LDA system off.
When the LDA system is turned on
or off, operation of the LDA system
continues in the same condition
the next time the hybrid system is
started.
WARNING
■Preventing LDA 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.
Turning LDA system on

PRIUS PRIME_OM_OM47C77U_(U)
3975-5. Using the driving support systems
5
Driving
LDA indicator
Illuminates when the LDA sys-
tem is on.
Steering control indicator and
operation display of steering
wheel operation support
When that steering wheel
assistance of the steering con-
trol 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-informat ion display is switched to the
screen. ( P. 243)
Indications on combination meter
1
2
3
Inside of displayed white lines
is whiteInside of displayed white lines
is black
Indicates that the system is recog-
nizing white (yellow) lines. 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 is tempo
rarily canceled.

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5-5. Using the driving support systems
■Operation conditions of each function
●Lane departure alert function
This function operates when all of the following conditions are met.
• LDA is turned on.
• Vehicle speed is approximately 32 mph (50 km/h) or more.
• System recognizes white (yellow) lines.
• Width of traffic lane is approximately 9.8 ft. (3 m) or more.
• Turn signal lever is not operated.
• Vehicle is driven on a straight road or around a gentle curve with a radius
of more than approximately 492 ft. (150 m).
• No system malfunctions are detected. ( P. 401)
● Steering control 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 (“LDA Steering Assist Mode”) in the screen of
the multi-information display is set to “On”. ( P. 218)
• Vehicle is not accelerated or decelerated by a certain 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.
● Vehicle sway warning function
This function operates when all of the following conditions are met.
• Setting for (“Lane Sway Warning Status”) in the screen of the multi-information display is set to “On”. ( P. 218)
• 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. 401)
■ Temporary cancellation of functions
When the operation conditions are no longer met, a function may be tempo-
rarily canceled. However, when the operation conditions are met again, oper-
ation of the function is automatically restored. ( P. 398)
■ Steering control 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.

PRIUS PRIME_OM_OM47C77U_(U)
3995-5. Using the driving support systems
5
Driving
■Lane departure alert function
The warning buzzer may be difficult to hear due to external noi se, audio play-
back, etc.
■ Hands off steering wheel warning
If the driver continues to keep their hands off of the steering wheel, a buzzer
sounds and a warning message and the symbol shown in the illust ration are
displayed on the multi-information display. This warning also o perates in the
same way when the driver continuously operates the steering whe el only a
small amount. Always keep your hands on the steering wheel when using this
system, regardless of warnings.
Depending on the vehicle and road conditions, the warning may n ot operate.
■ Vehicle sway warning function
■ White (yellow) lines are only on one side of road
The LDA system will not operate for the side on which white (yellow) lines
could not be recognized. When the system determines that the
driver has removed their hands from the
steering wheel while the steering control
function is operating, a warning message
urging the driver to hold the steering
wheel and the symbol shown in the illus-
tration are displayed on the multi-informa-
tion display.
When the system determines that the
vehicle is swaying while the vehicle sway
warning function is operating, a buzzer
sounds and a warning message urging
the driver to rest and the symbol shown in
the illustration are simultaneously dis-
played on the multi-information display.
Depending on the vehicle and road condi-
tions, the warning may not operate.

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PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
■Conditions in which functions may not operate properly
In the following situations, the camera sensor may not detect w hite (yellow)
lines and various functions may not operate normally.
● 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, “Botts’ dots”, “Raised pa vement
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 re cognize 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.
● The vehicle is driven on a surface that is bright due to reflec ted light, etc.
● The vehicle is driven in an area where the brightness changes s uddenly,
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 where the road diverges, merges, etc.
● 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 vehicle is driven around a sharp curve.
● 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 co nditions
during driving (poor roads or road seams).
● The headlight lenses are dirty and emit a faint amount of light at night, or the
beam axis has deviated.
● The vehicle is struck by a crosswind.
● The vehicle has just changed lanes or crossed an intersection.
● Snow tires, etc. are equipped.