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Driving
■Lane departure alert function
The warning buzzer may be difficult to hear due to external noi se, audio play-
back, etc.
■ Hands off steering wheel warning
If the driver continues to keep their hands off of the steering wheel, a buzzer
sounds and a warning message and the symbol shown in the illust ration are
displayed on the multi-information display. This warning also o perates in the
same way when the driver continuously operates the steering whe el only a
small amount. Always keep your hands on the steering wheel when using this
system, regardless of warnings.
Depending on the vehicle and road conditions, the warning may n ot operate.
■ Vehicle sway warning function
■ 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. When the system determines that the
driver has removed their hands from the
steering wheel while the steering control
function is operating, a warning message
urging the driver to hold the steering
wheel and the symbol shown in the illus-
tration are displayed on the multi-informa-
tion display.
When the system determines that the
vehicle is swaying while the vehicle sway
warning function is operating, a buzzer
sounds and a warning message urging
the driver to rest and the symbol shown in
the illustration are simultaneously dis-
played on the multi-information display.
Depending on the vehicle and road condi-
tions, the warning may not operate.
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PRIUS PRIME_OM_OM47C77U_(U)
4015-5. Using the driving support systems
5
Driving
■Warning message
If the following warning message is displayed on the multi-information dis-
play, follow the appropriate troubleshooting procedure.
If a different warning message is displayed, follow the instructions displayed
on the screen.
Warning messageDetails/Actions
“Lane Departure Alert
Malfunction
Visit Your Dealer”The system may not be operating
properly.
Have the vehicle inspected at your
Toyota dealer.
“Front Camera
Unavailable
See Owner’s Manual”
Dirt, rain, condensation, ice, snow,
etc. are present on the windshield in
front of the camera sensor.
Turn the LDA system off, remove
any dirt, rain, condensation, ice,
snow, etc. from the windshield, and
then turn the LDA system back on.
“Front Camera
Unavailable”
The operation conditions of the cam-
era sensor (temperature, etc.) are not
met.
When the operation conditions of
the camera sensor (temperature,
etc.) are met, the LDA system will
become available. Turn the LDA
system off, wait for a little while,
and then turn the LDA system back
on.
“Lane Departure Alert
Unavailable”
The LDA system is temporarily can-
celed due to a malfunction in a sensor
other than the camera sensor.
Turn the LDA system off and follow
the appropriate troubleshooting
procedures for the warning mes-
sage. Afterward, drive the vehicle
for a short time, and then turn the
LDA system back on.
“Lane Departure Alert
System is Unavailable
Below Approx. 32 MPH.”The LDA system cannot be used as
the vehicle speed is less than approxi-
mately 32 mph (50 km/h).
Drive the vehicle at approximately
32 mph (50 km/h) or more.
Page 403 of 792
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Driving
Dynamic radar cruise controlwith full-speed
range
In vehicle-to-vehicle distance control mode, the vehicle automa tically
accelerates, decelerates and st ops to match the speed changes o f the
preceding vehicle even if the acc elerator pedal is not depressed. In
constant speed control mode, t he vehicle runs at a fixed speed.
Use the dynamic radar cruise control with full-speed range on f ree-
ways and highways.
● Vehicle-to-vehicle distance control mode ( P. 407)
● Constant speed c ontrol mode (P. 414)
Vehicle-to-vehicle distance
switch
Indicators
Display
Set speed
Cruise control switch
Summary of functions
1
2
3
4
5
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PRIUS PRIME_OM_OM47C77U_(U)
4095-5. Using the driving support systems
5
Driving
Press the “ON-OFF” button to
activate the cruise control.
Radar cruise control indicator will
come on and a message will be
displayed on the multi-information
display.
Press the button again to deacti-
vate the cruise control.
If the “ON-OFF” button is pressed
and held for 1.5 seconds or more,
the system turns on in constant
speed control mode. ( P. 414)
Accelerate or decelerate, with
accelerator pedal operation, to
the desired vehicle speed (at or
above approximately 30 mph
[50 km/h]) and push the lever
down to set the speed.
Cruise control “SET” indicator will
come on.
The vehicle speed at the moment
the lever is released becomes the
set speed.
If the lever is operated while the vehicle speed is below appro ximately 30
mph (50 km/h) and a preceding vehicle is present, the set speed will be
adjusted to approximately 30 mph (50 km/h).
Setting the vehicle speed (vehicle-to-vehicle distance control
mode)
1
2
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PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
To change the set speed, operate the lever until the desired se t speed
is displayed.
Increases the speed
(Except when the vehicle has been
stopped by system control in vehi-
cle-to-vehicle distance control
mode)
Decreases the speed
Fine adjustment: Momentarily
move the lever in the desired
direction.
Large adjustment: Hold the lever up or down to change the speed ,
and release when the des ired speed is reached.
In the vehicle-to-vehicle distance control mode, the set speed will be
increased or decreased as follows:
For the U.S. mainland and Hawaii
Fine adjustment: By 1 mph (1.6 km/h)
*1 or 1 km/h (0.6 mph)*2 each time
the lever is operated
Large adjustment: Increases or decreases in 1 mph (1.6 km/h)
*1 or 1 km/h
(0.6 mph)
*2 increments for as long as the lever is held
For Canada
Fine adjustment: By 1 mph (1.6 km/h)
*1 or 1 km/h (0.6 mph)*2 each time
the lever is operated
Large adjustment: Increases or decreases in 5 mph (8 km/h)
*1 or 5 km/h
(3.1 mph)
*2 increments for as long as the lever is held
In the constant speed control mode ( P. 414), the set speed will be
increased or decreased as follows:
Fine adjustment: By 1 mph (1.6 km/h)*1 or 1 km/h (0.6 mph)*2 each time
the lever is operated
Large adjustment: The speed will continue to change while the l ever is
held.
*1: When the set speed is shown in “MPH”
*2: When the set speed is shown in “km/h”
Adjusting the set speed
1
2
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PRIUS PRIME_OM_OM47C77U_(U)
4115-5. Using the driving support systems
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Driving
Pressing the switch changes the
vehicle-to-vehicle distance as fol-
lows:Long
Medium
Short
The vehicle-to-vehicle distance is
set automatically to long mode
when the power switch is turned to
ON mode.
If a vehicle is running ahead of you, the preceding vehicle mark will also be
displayed.
Select a distance from the tabl e below. Note that the distances shown
correspond to a vehicle speed of 50 mph (80 km/h). Vehicle-to-v ehicle
distance increases/decreases in accordance with vehicle speed.
When the vehicle is stopped by system control, the vehicle stop s at a
certain vehicle-to-vehicle dista nce depending on the situation.
Changing the vehicle-to-vehicle d istance (vehicle-to-vehicle dis-
tance control mode)
Preceding
vehicle mark
1
2
3
Vehicle-to-vehicle distance settings (vehicle-to-vehicle distan ce
control mode)
Distance optionsVehicle-to-vehicle distance
LongApproximately 160 ft. (50 m)
MediumApproximately 130 ft. (40 m)
ShortApproximately 100 ft. (30 m)
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PRIUS PRIME_OM_OM47C77U_(U)
4135-5. Using the driving support systems
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Driving
When your vehicle is too close to
a vehicle ahead, and sufficient
automatic deceleration via the
cruise control is not possible, the
display will flash and the buzzer
will sound to alert the driver. An
example of this would be if
another driver cuts in front of you
while you are following a vehicle.
Depress the brake pedal to
ensure an appropriate vehicle-to-
vehicle distance.
■Warnings may not occur when
In the following instances, war nings may not occur even when th e
vehicle-to-vehicle distance is small.
● When the speed of the preceding vehicle matches or exceeds
your vehicle speed
● When the preceding vehicle is traveling at an extremely slow
speed
● Immediately after the cruise control speed was set
● When depressing the accelerator pedal
Approach warning (vehicle-to-v ehicle distance control mode)
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5-5. Using the driving support systems
■Automatic cancelation of c onstant speed control mode
Constant speed control mode is automatically canceled in the following situa-
tions:
● Actual vehicle speed is more than approximately 10 mph (16 km/h ) below
the set vehicle speed.
● Actual vehicle speed falls below approximately 25 mph (40 km/h) .
● VSC is activated.
● TRAC is activated for a period of time.
● When the VSC or TRAC system is turned off.
● Pre-collision braking is activated.
● Parking Support Brake function is operated. (if equipped)
If constant speed control mode is automatically canceled for an y other rea-
son, there may be a malfunction in the system. Contact your Toyota dealer.
■ Brake system operation sound
If the brakes are applied automatically while the vehicle is in vehicle-to-vehi-
cle distance control mode, a brake system operation sound may b e heard.
This does not indicate a malfunction.
■ Warning messages and buzzers for d ynamic radar cruise control with
full-speed range
Warning messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. If a warning message
is shown on the multi-information display, read the message and follow the
instructions.