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5-5. Using the driving support systems
■Operational conditions
The pre-collision system is enabled and the system determines that the pos-
sibility of a frontal collision wi th a vehicle or pedestrian is high.
Each function is operational at the following speeds:
● Pre-collision warning:
• Vehicle speed is between approximately 7 and 110 mph (10 and 180 km/h).
(For detecting a pedestrian, vehicle speed is between approximately 7 and
50 mph [10 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 7 mph (10 km/h) or more.
● Pre-collision brake assist:
• Vehicle speed is between approximately 19 and 110 mph (30 and 180 km/h).
(For detecting a pedestrian, vehicle speed is between approximately 19 and
50 mph [30 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 19 mph (30 km/h) or more.
● Pre-collision braking:
• Vehicle speed is between approximately 7 and 110 mph (10 and 180 km/h).
(For detecting a pedestrian, vehicle speed is between approximately 7 and
50 mph [10 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian
ahead is approximately 7 mph (10 km/h) or more.
The system may not operate in the following situations:
● If a 12-volt battery terminal has been disconnected and reconnected and
then the vehicle has not been driven for a certain amount of time
● If the shift position is in R
● If VSC is disabled (only the pre-collision warning function will be opera-
tional)
● If the PCS warning light is flashing or illuminated
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5-5. Using the driving support systems
■If the PCS warning light flashes a nd a warning message is displayed on
the multi-information display
The pre-collision system may be tem porarily unavailable or there may be a
malfunction in the system.
● In the following situations, the warning light will turn off, the message will
disappear and the system will become operational when normal operating
conditions return:
• When the radar sensor or camera sensor or the area around either sen-
sor is hot, such as in the sun
• When the radar sensor or camera sensor or the area around either sen- sor is cold, such as in an extremely cold environment
• When the radar sensor or front grille emblem 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. 491, 501)
• 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 the warning message does not
disappear, the system may be malfunctioning. Have the vehicle inspected
by your Toyota dealer immediately.
■ If VSC is disabled
●If VSC is disabled ( →P. 478), 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.
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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.
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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.
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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 malfunctio ns 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.
Turning LDA system on
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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. 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)
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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.