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PRIUS PRIME_OM_OM47A88U_(U)
3715-5. Using the driving support systems
5
Driving
WARNING
■Limitations of the pre-collision system
● The driver is solely responsible for safe driving. Always drive safely, taking
care to observe your surroundings.
Do not use the pre-collision system instead of normal braking operations
under any circumstances. This system will not prevent collisions or lessen
collision damage or injury in every situation. Do not overly rely on this sys-
tem. Failure to do so may lead to an accident, resulting in death or serious
injury.
● Although this system is designed to help avoid a collision or help reduce
the impact of the collision, its effectiveness may change according to vari-
ous conditions, therefore the system may not always be able to achieve
the same level of performance.
Read the following conditions carefully. Do not overly rely on this system
and always drive carefully.
• Conditions under which the system may operate even if there is no pos-
sibility of a collision: →P. 375
• Conditions under which the system may not operate properly: →P. 377
● Do not attempt to test the operation of the pre-collision system yourself, as
the system may not operate properly, possibly leading to an accident.
■ Pre-collision braking
● When the pre-collision braking function is operating, a large amount of
braking force will be applied.
● If the vehicle is stopped by the operation of the pre-collision braking func-
tion, the pre-collision braking func tion operation will be canceled after
approximately 2 seconds. Depress the brake pedal as necessary.
● The pre-collision braking function may not operate if certain operations are
performed by the driver. If the accelerator pedal is being depressed
strongly or the steering wheel is being turned, the system may determine
that the driver is taking evasive action and possibly prevent the pre-colli-
sion braking function from operating.
● In some situations, while the pre-collision braking function is operating,
operation of the function may be canceled if the accelerator pedal is
depressed strongly or the steering wheel is turned and the system deter-
mines that the driver is taking evasive action.
● If the brake pedal is being depressed, the system may determine that the
driver is taking evasive action and possibly delay the operation timing of
the pre-collision braking function.
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PRIUS PRIME_OM_OM47A88U_(U)
3755-5. Using the driving support systems
5
Driving
■Pedestrian detection function
■ Cancelation of the pre-collision braking
If either of the following occur while the pre-collision braking function is oper-
ating, it will be canceled:
●The accelerator pedal is depressed strongly.
● The steering wheel is turned sharply or abruptly.
■ Conditions under which the system ma y operate even if there is no pos-
sibility of a collision
● In some situations such as the following, the system may determine that
there is a possibility of a frontal collision and operate.
• When passing a vehicle or pedestrian
• When changing lanes while overtaking a preceding vehicle
• When overtaking a preceding vehicle that is changing lanes
The pre-collision system detects pedestri-
ans based on the size, profile, and motion
of a detected object. However, a pedes-
trian may not be detected depending on
the surrounding brightness and the
motion, posture, and angle of the
detected object, preventing the system
from operating properly. (→P. 379)
• When overtaking a preceding vehiclethat is making a left/right turn
• When passing a vehicle in an oncom- ing lane that is stopped to make a
right/left turn
Page 381 of 784
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PRIUS PRIME_OM_OM47A88U_(U)
5-5. Using the driving support systems
5
Driving
LDA (Lane Departure Al ert with steering
control)
When driving on highways and freeways with white (yellow) lines, this
function alerts the driver when th e vehicle might depart from its lane
and provides assistance by operatin g 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_OM47A88U_(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
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.
Page 383 of 784

PRIUS PRIME_OM_OM47A88U_(U)
3835-5. 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 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.
■ 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, resulting in
death or serious injury.
● Tire chains are equipped.
● When the tires have been excessively worn, or when the tire inflation pres-
sure is low.
● Tires which differ by structure, manufacturer, brand or tread pattern are
used.
● Objects or patterns that could be mistaken for white (yellow) lines 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 present 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.
Page 385 of 784
PRIUS PRIME_OM_OM47A88U_(U)
3855-5. 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-informatio n display is switched to the
screen. ( →P. 230)
Indications on combination meter
1
2
3
Inside of displayed white lines
is whiteInside 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 t
he system is not
able to recognize white (yellow)
lines or is temporarily canceled.
Page 386 of 784

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PRIUS PRIME_OM_OM47A88U_(U)
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. 389)
● 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. 231)
• 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.
● Vehicle sway warning
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. 231)
• 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. 389)
Page 387 of 784

PRIUS PRIME_OM_OM47A88U_(U)
3875-5. Using the driving support systems
5
Driving
■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. 386)
● When operation conditions are no longer met while operating the steering
control function, a buzzer may sound to indicate that a function may be tem-
porarily canceled. ( →P. 386)
■ 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.
■ Lane departure alert function
The warning buzzer may be difficult to hear due to external noise, audio play-
back, etc.
■ Hands off steering wheel alert
When the system determines that the driver has removed the hands from the
steering wheel while the steering control function is operating, a warning
message is displayed on the multi-information display and the buzzer
sounds.
■ 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.