TOYOTA PRIUS PRIME 2021 Owners Manual (in English)

PRIUS PRIME_OM_OM47D71U_(U)
3915-5. Using the driving support systems
5
Driving
• When there are patterns or paint in front of your vehicle that may be mis-
taken for a detectable object
• When the front of your vehicle is hit by water, snow, dust, etc.
• When a detectable object approaches very close and then stops before
entering the path of your vehicle
• If the front of your vehicle is raised or lowered, such as when on an
uneven or undulating road surface
• When driving on a road surrounded by a structure, such as in a tunnel or
on an iron bridge
• When there is a metal object (manhole cover, steel plate, etc.), steps, or a
protrusion in front of your vehicle
• When approaching an electric toll gate barrier, parking area barrier, or
other barrier that opens and closes
• When using an automatic car wash • When there is a detectable object or
other object by the roadside at the
entrance of a curve
• When overtaking a detectable object
that is changing lanes or making a
right/left turn
• When passing a detectable object in
an oncoming lane that is stopped to
make a right/left turn
• When passing under an object (road
sign, billboard, etc.)

392
PRIUS PRIME_OM_OM47D71U_(U)
5-5. Using the driving support systems
• When driving through steam or smoke
• When driving near an object that reflects radio waves, such as a large
truck or guardrail
• When driving near a TV tower, broadcasting station, electric power plant,
or other location where strong radio waves or electrical noise may be
present
■Situations in which the system may not operate properly
●In some situations such as the following, an object may not be detected by
the radar sensor and front camera, preventing the system from operating
properly:
• When a detectable object is approaching your vehicle
• When your vehicle or a detectable object is wobbling
• If a detectable object makes an abrupt maneuver (such as sudden swerv-
ing, acceleration or deceleration)
• When your vehicle approaches a detectable object rapidly
• When a detectable object is near a wall, fence, guardrail, manhole cover,
vehicle, steel plate on the road, etc.
• When a detectable object is under a structure
• When part of a detectable object is hidden by an object, such as large
baggage, an umbrella, or guardrail
• When multiple detectable objects are close together
• If the sun or other light is shining directly on a detectable object
• When a detectable object is a shade of white and looks extremely bright
• When a detectable object appears to be nearly the same color or bright-
ness as its surroundings
• If a detectable object cuts or suddenly emerges in front of your vehicle
• When the front of your vehicle is hit by water, snow, dust, etc.
• When a very bright light ahead, such as the sun or the headlights of
oncoming traffic, shines directly into the front camera
• When approaching the side or front of a vehicle ahead
• If a vehicle ahead is a motorcycle • When driving through or under
objects that may contact your vehicle,
such as thick grass, tree branches, or
a banner
• When a detectable object is not
directly in front of your vehicle

PRIUS PRIME_OM_OM47D71U_(U)
3935-5. Using the driving support systems
5
Driving
• If a vehicle ahead is narrow, such as a personal mobility vehicle
• If a preceding vehicle has a small rear end, such as an unloaded truck
• If a vehicle ahead is carrying a load which protrudes past its rear bumper
• If a vehicle ahead is irregularly shaped, such as a tractor or side car
• If a vehicle ahead is a child sized bicycle, a bicycle that is carrying a large
load, a bicycle ridden by more than one person, or a uniquely shaped
bicycle (bicycle with a child seat, tandem bicycle, etc.)
• If a pedestrian/or the riding height of a bicyclist ahead is shorter than
<00440053005300550052005b004c0050004400570048004f005c000300160011001500030049005700110003000b001400030050000c000300520055000300570044004f004f0048005500030057004b00440051000300440053005300550052005b004c00
50004400570048004f005c0003001900110018000300490057[. (2 m)
• If a pedestrian/bicyclist is wearing oversized clothing (a rain coat, long
skirt, etc.), making their silhouette obscure
• If a pedestrian is bending forward or squatting or bicyclist is bending for-
ward
• If a pedestrian/bicyclist is moving fast
• If a pedestrian is pushing a stroller, wheelchair, bicycle or other vehicle
• When driving in inclement weather such as heavy rain, fog, snow or a
sandstorm
• When driving through steam or smoke
• When the surrounding area is dim, such as at dawn or dusk, or while at
night or in a tunnel, making a detectable object appear to be nearly the
same color as its surroundings
• When driving in a place where the surrounding brightness changes sud-
denly, such as at the entrance or exit of a tunnel
• After the hybrid system has started the vehicle has not been driven for a
certain amount of time
• While making a left/right turn and for a few seconds after making a left/
right turn
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding • If a preceding vehicle has a low rear
end, such as a low bed trailer
• If a vehicle ahead has extremely high
ground clearance

394
PRIUS PRIME_OM_OM47D71U_(U)
5-5. Using the driving support systems
• If the wheels are misaligned
• If a wiper blade is blocking the front camera
• The vehicle is being driven at extremely high speeds
• When driving on a hill
• If the radar sensor or front camera is misaligned
●In some situations such as the following, sufficient braking force 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 slippery sur-
face
■If VSC is disabled
●If VSC is disabled (P. 503), 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-Collision Brake
System Unavailable” will be displayed on the multi-information display. • If the front of the vehicle is raised or
lowered

395
PRIUS PRIME_OM_OM47D71U_(U)
5-5. Using the driving support systems
5
Driving
LTA (Lane Tracing Assist)
While driving on a road with clear white (yellow) lane lines, the LTA
system warns the driver if the vehicle may deviate from the current
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-speed range is operating, this system will
operate the steering wheel to maintain 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

396
PRIUS PRIME_OM_OM47D71U_(U)
5-5. Using the driving support systems
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 inflation 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 surface 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, do not install a
grille guard (bull bars, kangaroo bar, etc.).
●If your windshield needs repairs, contact your Toyota dealer.

PRIUS PRIME_OM_OM47D71U_(U)
3975-5. Using the driving support systems
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. 405) 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. 405) 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. 405) 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. 405) 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.).

398
PRIUS PRIME_OM_OM47D71U_(U)
5-5. Using the driving support systems
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, “Botts’ dots”, “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.
●<0037004b0048000300590048004b004c0046004f00480003004c0056000300470055004c00590048005100030052005100030044000300450055004c004a004b005700030056005800550049004400460048000f0003005600580046004b00030044005600
03004600520051004600550048005700480011[
●If the edge of the road is not clear or straight.
●<0037004b0048000300590048004b004c0046004f00480003004c0056000300470055004c005900480051000300520051000300440003005600580055004900440046004800030057004b004400570003004c0056000300450055004c004a004b0057000300
47005800480003005700520003005500480049004f00480046[ted 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.

PRIUS PRIME_OM_OM47D71U_(U)
3995-5. Using the driving support systems
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.
●<0037004b0048000300590048004b004c0046004f00480003004c0056000300470055004c00590048005100030052005100030044000300550052004400470003005a004b004c0046004b00030057004c004f005700560003004f0048004900570003005200
5500030055004c004a004b0057000f00030052005500030044[ 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.
●<0037004b004800030047004c00560057004400510046004800030057005200030057004b00480003005300550048004600480047004c0051004a000300590048004b004c0046004f00480003004c005600030048005b00570055004800500048004f005c00
030056004b0052005500570011[
●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.
●<0037004b0048000300590048004b004c0046004f00480003004b004400560003004d00580056005700030046004b00440051004a004800470003004f0044005100480056000300520055000300460055005200560056004800470003004400510003004c00
510057004800550056004800460057004c005200510011[
●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.
●<0037004b0048000300590048004b004c0046004f00480003004c0056000300450048004c0051004a000300470055004c00590048005100030044005700030048005b00570055004800500048004f005c0003004b004c004a004b0003005600530048004800
4700560011[

400
PRIUS PRIME_OM_OM47D71U_(U)
5-5. Using the driving support systems
■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