2014 TOYOTA PRIUS Owners Manual

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When driving
LKA (Lane-Keeping Assist)
: If equipped
While driving on a freeway or motor highway that has lane markers
and no sharp curves, the system recognizes the lanes using a cam-
era located above the inside rear view mirror as a sensor to assist
the driver with staying in the lane. The LKA system has two func-
tions.
Camera sensor

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Functions included in the LKALane departure warning function
If the system judges th at the vehicle may deviate from its lane, it
alerts the driver using beeping, screen displays and a sensory
warning
* given via the steering wheel.
*: A slight steering torque is applied for a short period of time in the direc- tion of the center of the lane.
Lane keeping assist function
• This function will be active wh en the vehicle-to-vehicle distance
control mode of the cruise control ( P. 272) is set with vehicle
speed above approximately 45 mph (72 km/h) and while the
lane departure warning function is active.
• When the lane keeping assist function is active, a slight steering torque will be applied, to help the driver maintain the vehicle
inside the lane.
The lane keeping assist function will be temporarily canceled if the steer-
ing wheel is not operated, or if you continue driving with your hands
lightly touching the steering wheel. ( P. 294)

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When driving
Turning the LKA system on
Press the “LKA” switch to acti-
vate the system.
“LKA” indicator will come on.
Press the switch again to turn the
LKA system off.
The LKA system will revert to off
each time the power switch is
turned to ON mode.

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Operating conditions for each function■ Lane departure warning function
●When the vehicle speed is a pproximately 30 mph (48 km/h) or
more
● When the lane width is more than approximately 9.1 ft. (2.8 m)
● When driving on a straight road or through a curve with a radius
of more than approximately 394 ft. (120 m)
■ Lane keeping assist function
●When the vehicle speed is between approximately 45 and 112
mph (72 and 180 km/h)
● When the vehicle-to-vehicle distance mode of the radar cruise
control is on, and the set vehicl e speed is approximately 45 mph
(72 km/h) or more (the functi on will not operate when the radar
cruise control is in set speed mode)
● When the lane width is between approximately 9.1 and 13.1 ft.
(2.8 and 4.0 m)
● When driving on a straight road or through a curve with a radius
of more than approximately 656 ft. (200 m)

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When driving
Indication on the multi-information display
When the LKA system is on, the lane line display and steering wheel
display are shown. Lane keeping assist function
operation indication
Steering wheel displayed:
Indicates that the function is cur-
rently operating. (If the lane
departure warning operates at
this time, the steering wheel
flashes.)
Steering wheel not displayed:
Indicates that the function is not
currently operating. (When the
lane keeping assist function is
canceled, the buzzer will beep
twice.)
Dynamic radar cruise control
display
Lane departure warning func-
tion indication (when solid
lines are shown):
The function has recognized lane
markers. (If the lane departure
warning operates at this time, the
lines flash.)
Lane departure warning func-
tion indication (when thin lines
are shown):
A lane marker is not recognized
by the system, or the LKA system
functions are temporarily can-
celed.

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■Temporary cancelation of the LKA system functions
If any of the following occurs, the LKA system functions will be temporarily
canceled. The functions will resume after the necessary operating conditions
have returned.
● The steering wheel is turned as far as necessary to cause the vehicle to
change lanes.
● When the system detects no-handed driving. (The lane keeping assist
function will be temporarily canceled, but the lane departure warning
function will continue.)
● The turn signal lever is operated.
● The vehicle speed deviates from the operating range of the LKA system
functions. (The buzzer will beep twice when the lane keeping assist func-
tion is being canceled.)
● When the lane lines cannot be recognized while driving. (The buzzer will
beep twice when the lane keeping assist function is being canceled.)
● The wiper switch is set on high speed mode. (The lane keeping assist
function will be temporarily canceled, but the lane departure warning
function will continue.)
● If the vehicle crosses a line for approximately half a minute or more. (The
lane keeping assist function will be temporarily canceled, but the lane
departure warning function will continue.)
● When the lane departure warning function is activated.
The lane departure warning function will not operate again for a several
seconds after it has been activated, even if the vehicle leaves the lane
again.
■ The lane departure warning
It may be difficult to feel the sensory warning depending on the road condi-
tions.

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When driving
■No-handed driving warning
If the steering wheel is not operated for approximately 15 seconds on a
straight road or approximately 5 seconds on a curve, the buzzer will beep
twice, indicators on the multi-information display will flash, and the lane
keeping assist function will be temporarily canceled. If you drive the vehicle
with your hands lightly touching the steering wheel, this may also be
detected as no-handed driving.
■ After the vehicle has been parked in the sun
The LKA system functions may not be available and a warning message
(P. 520) will be displayed for a while after driving has started. In such
cases, turn the LKA system off and turn it on again after normal temperature
returns. When the temperature in the cabin decreases and the temperature
around the camera sensor ( P. 289) becomes suitable for its operation, the
functions will begin to operate.
■ If there are lane markers on only one side of the vehicle
The lane keeping assist function will not operate. Also, the lane departure
warning will not operate for the side on which lane markers could not be rec-
ognized.
■ Conditions in which the function may not operate correctly
In the following conditions, the LKA system functions may not operate, or it
may not be possible to ensure adequate performance. Also, the camera
sensor may be unable to recognize lane lines causing the lane departure
warning function to operate incorrectly, or the lane keeping assist function
may not operate properly. However, this does not indicate a malfunction.
●When driving through an area with no lane markers, such as a tollbooth,
a crossing or before a ticket checkpoint
● When driving on a sharp curve
● When lanes are extremely narrow or extremely wide
● When the vehicle leans to one side an unusual amount due to a heavy
load or improper tire inflation pressure
● When the following distance between your vehicle and the vehicle ahead
is extremely short

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●When the lane markers are yellow (These may be more difficult for the
system to recognize compared to white markers.)
● When the lane markers are broken, “Botts’ dots”, “Raised pavement
marker” or stones
● When lane markers are obscured or partially obscured by sand, dirt, etc.
● When there are shadows on the road running parallel with lane markers,
or if a shadow covers the lane markers
● When driving on a particularly bright road surface, such as concrete
● When driving on a road surface that is bright due to reflected light
● When driving in a location where the light level changes rapidly, such as
the entrance to or exit from a tunnel
● When sunlight or the headlights of oncoming vehicles are shining directly
into the camera lens
● When driving on roads that are branching or merging
● When driving on a road surface that is wet due to rain, previous rainfall,
standing water, etc.
● When the vehicle experiences strong up-and-down motion such as when
driving on an extremely rough road or on a seam in the pavement
● When headlight brightness at nighttime is reduced due to dirt on the
lenses, or when the headlights are misaligned
● When driving with a strong crosswind
● When driving on winding roads or roads that are uneven
● When driving on rough or unpaved roads
■ When changing the tires
Depending on the tires used, sufficient performance may not be maintain-
able.
■ Warning messages for LKA
Warning messages are used to indicate a system malfunction or to inform
the driver of the need for caution while driving. (P. 516, 520)