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PRIUS PRIME_OM_OM47D13U_(U)
4095-5. Using the driving support systems
5
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
When constant speed control mode is selected, your vehicle will main-
tain a set speed without controllin g the vehicle-to-vehicle distance.
Select this mode only when vehic le-to-vehicle distance control mode
does not function correctly due to a dirty radar sensor, etc.
With the cruise control off,
press and hold the “ON-OFF”
button for 1.5 seconds or more.
Immediately after the “ON-OFF”
button is pressed, the radar cruise
control indicator will come on.
Afterwards, it switches to the cruise
control indicator.
Switching to constant speed con-
trol mode is only possible when
operating the lever with the cruise
control off.
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.
Adjusting the speed setting: P. 406
Canceling and resuming the speed setting: P. 408
Selecting constant speed control mode
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PRIUS PRIME_OM_OM47D13U_(U)
4115-5. Using the driving support systems
5
Driving
■Dynamic radar cruise control wi th full-speed range can be set when
● The shift position is in D.
● Vehicle speed is at or above approximately 30 mph (50 km/h).
However, when a preceding vehicle is detected, the dynamic rada r cruise
control with full-speed range can be set even if the vehicle speed is at or
below approximately 30 mph (50 km/h).
■ Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal. After acceler-
ating, the set speed resumes. However, during vehicle-to-vehicl e distance
control mode, the vehicle speed may decrease below the set spee d in order
to maintain the distance to the preceding vehicle.
■ When the vehicle stops while follow-up cruising
●Pushing the lever up while the vehicle ahead stops will resume follow-up
cruising if the vehicle ahead starts off within approximately 3 seconds after
the lever is pushed up.
● If the vehicle ahead starts off within 3 seconds after your veh icle stops, fol-
low-up cruising will be resumed.
■ Automatic cancelation of vehicle-to-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically cance led in the fol-
lowing situations:
● Actual vehicle speed falls at or below approximately 25 mph (40 km/h) when
there are no vehicles ahead.
● The preceding vehicle leaves the lane when your vehicle is following at a
vehicle speed at or below approximately 25 mph (40 km/h). Other wise, the
sensor can not properly detect the vehicle.
● VSC is activated.
● TRAC is activated for a period of time.
● When the VSC or TRAC system is turned off.
● The sensor cannot detect correctly because it is covered in some way.
● Pre-collision braking is activated.
● Intelligent Clearance Sonar is operated. (if equipped)
● The parking brake is operated.
● The vehicle is stopped by system control on a steep incline.
● The following are detected when the vehicle has been stopped by system
control:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes.
In this situation, the shift position may automatically switch to P. (P. 341)
If vehicle-to-vehicle distance control mode is automatically ca nceled for any
other reason, there may be a malfunction in the system. Contact your Toyota
dealer.
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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.
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.
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PRIUS PRIME_OM_OM47D13U_(U)
4135-5. Using the driving support systems
5
Driving
■When the sensor may not be correctly detect ing the vehicle ahead
In the case of the following and depending on the conditions, o perate the
brake pedal when deceleration of the system is insufficient or operate the
accelerator pedal when acceleration is required.
As the sensor may not be able to correctly detect these types o f vehicles, the
approach warning ( P. 409) will not be activated.
● Vehicles that cut in suddenly
● Vehicles traveling at low speeds
● Vehicles that are not moving in the same lane
● Vehicles with small rear ends (trailers with no load on board, etc.)
● Motorcycles traveling in the same lane
● When water or snow thrown up by the surrounding vehicles hinders the
detecting of the sensor
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)
● Preceding vehicle has an extremely high
ground clearance
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PRIUS PRIME_OM_OM47D13U_(U)
5-5. Using the driving support systems
■Conditions under which the vehic le-to-vehicle distance control mode
may not function correctly
In the case of the following conditions, operate the brake peda l (or accelera-
tor pedal, depending on the situation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system
may not operate properly.
● When the vehicle ahead of you decelerates suddenly
● When driving on a road surrounded by a structure, such as in a tunnel or on
a bridge
● While the vehicle speed is decreasing to the set speed after th e vehicle
accelerates by depressing the accelerator pedal
●
When the road curves or when the lanes
are narrow
● When steering wheel operation or your
position in the lane is unstable
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Driving
Driving mode select switch
Repeatedly press the switch unt il the system changes to the intended
driving mode.
Each time the switch is pressed, the driving mode changes in th e following
order and the
“ECO MODE” and “PWR MODE” indicators turn on or off
accordingly.
In response to driving conditions, one of 3 driving modes can b e
selected.
Driving modes
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Normal mode
Suitable for normal driving.
When normal mode is selected, the “ECO MODE” and “PWR MODE”
indicators turn off.
Power mode
Suitable for when crisp handling and enhanced accelerator
response are desired, such as when driving on mountainous roads .
When power mode is selected, the “PWR MODE” indicator will illu mi-
nate on the main display.
Eco drive mode
Suitable for driving that impro ves fuel economy by generating
torque in response to accelerator pedal operations more smoothl y
than in normal mode.
When Eco drive mode is selected, the “ECO MODE” indicator will illumi-
nate on the main display.
While the air conditioning is being used, the system automatically
switches to air conditioning eco mode (P. 499, 510), allowing for driv-
ing that leads to even better fuel economy.
■ The driving mode after turning the power switch off
The driving mode will not be changed automatically until the switch is
pressed, even if the power switch is turned off.
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