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PRIUS PRIME_OM_OM47E74U_(U)
3775-5. Using the driving support systems
5
Driving
SituationActions
When the area around a cam-
era is covered with dirt, mois-
ture (fogged up, covered with
condensation, ice, etc.), or
other foreign matter
Using the wiper and A/C function,
remove the dirt and other attached mat-
ter. (P. 511, 523)
When the temperature around
the front camera is outside of
the operational range, such as
when the vehicle is in the sun or
in an extremely cold environ-
ment
If the front camera is hot, such as after
the vehicle had been parked in the sun,
use the air conditioning system to
decrease the temperature around the
front camera.
If a sunshade was used when the vehi-
cle was parked, depending on its type,
the sunlight reflected from the surface
of the sunshade may cause the tem-
perature of the front camera to become
excessively high.
If the front camera is cold, such after the
vehicle is parked in an extremely cold
environment, use the air conditioning
system to increase the temperature
around the front camera.
The area in front of the front
camera is obstructed, such as
when the hood is open or a
sticker is attached to the part of
the windshield in front of the
front camera.
Close the hood, remove the sticker, etc.
to clear the obstruction.
When “Pre-Collision System
Unavailable” is displayed.Check whether there is attached materi-
als on the radar sensor and radar sensor
cover, and if there is, remove it.
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PRIUS PRIME_OM_OM47E74U_(U)
5-5. Using the driving support systems
●In the following situations, if the situation has changed (or the vehicle has
been driven for some time) and the normal operating conditions are
detected, the message will disappear and the system will become opera-
tional.
If the message does not disappear, contact your Toyota dealer. • When the temperature around the radar sensor is outside of the opera-
tional range, such as when the vehicle is in the sun or in an e xtremely
cold environment
• When the front camera cannot detect objects in front of the ve hicle, such
as when driving in the dark, snow, or fog, or when bright lights are shining
into the front camera
• Depending on the conditions in the vicinity of the vehicle, th e radar may
judge the surrounding environment can not be properly recognize d. In
that case, “Pre-Collision Syst em Unavailable” is displayed.
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PRIUS PRIME_OM_OM47E74U_(U)
5-5. Using the driving support systems
■Pre-collision warning
When the system determines
that the possibility of a frontal
collision is high, a buzzer will
sound and a warning message
will be displayed on the multi-
information display to urge the
driver to take evasive action.
■Pre-collision brake assist
When the system determines that the possibility of a frontal colli-
sion is high, the system applies greater braking force in relat ion to
how strongly the brake pedal is depressed.
■Pre-collision braking
If the system determines that the possibility of a frontal collision is
extremely high, the brakes are automatically applied to help avoid
the collision or reduce th e impact of the collision.
System functions
Page 383 of 808
PRIUS PRIME_OM_OM47E74U_(U)
3835-5. Using the driving support systems
5
Driving
■Enabling/disabling th e pre-collision system
The pre-collision system can be enabled/disabled on ( P. 246)
of the multi-information display.
The system is automatically enabled each time the power switch is
turned to ON mode.
If the system is disabled, the
PCS warning light will turn on
and a message will be dis-
played on the multi-information
display.
■Changing the pre-colli sion warning timing
The pre-collision warning timing can be changed on ( P. 246)
of the multi-information display.
The warning timing setting is retained when the power switch is turned
off.
However, if the pre-collision system is disabled and re-enabled , the
operation timing will return to the default setting (middle).
Early
Middle
This is the default setting.
Late
Changing settings of the pre-collision system
1
2
3
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PRIUS PRIME_OM_OM47E74U_(U)
3895-5. Using the driving support systems
5
Driving
• 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 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
■ If VSC is disabled
●If VSC is disabled ( P. 498), 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.
• If the front of the vehicle is raised or
lowered
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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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PRIUS PRIME_OM_OM47E74U_(U)
3955-5. Using the driving support systems
5
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.