2020 TOYOTA PRIUS PRIME brake

PRIUS PRIME_OM_OM47C77U_(U)
4135-5. 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)

PRIUS PRIME_OM_OM47C77U_(U)
4155-5. 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 sp eed is 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.
● Parking Support Brake function 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. 345)
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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PRIUS PRIME_OM_OM47C77U_(U)
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.

PRIUS PRIME_OM_OM47C77U_(U)
4175-5. 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. 413) may 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_OM47C77U_(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

PRIUS PRIME_OM_OM47C77U_(U)
4395-5. Using the driving support systems
5
Driving
■If “Clean Parking Assist Sensor” is displayed on the multi-info rmation
display
A sensor may be dirty or covered with snow or ice. In such case s, if it is
removed from the sensor, the system should return to normal.
Also, due to the sensor being frozen at low temperatures, a malfunction dis-
play may appear or an obstacle may not be detected. If the sensor thaws out,
the system should return to normal.
■ If “Parking Assist Malfunction” is displayed on the multi-infor mation dis-
play
Depending on the malfunction of the sensor, the device may not be working
normally. Have the vehicle inspected by your Toyota dealer.
■ Certification (Canada only)
This ISM device complies with Canadian ICES-001.
■ Customization
Settings (e.g. buzzer volume) can be changed.
(Customizable features: P. 741)
WARNING
■When using intuitive parking assist
Observe the following precautions to avoid an unexpected accident.
● Do not exceed the speed limit of 6 mph (10 km/h).
● The sensors’ detection areas and reaction times are limited. When moving
forward or reversing, check the areas surrounding the vehicle ( especially
the sides of the vehicle) for safety, and drive slowly, using t he brake to
control the vehicle’s speed.
● Do not install accessories within the sensors’ detection areas.

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PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
WARNING
■Sensors
Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where
this may occur are listed below.
● There is dirt, snow or ice on the sensor. (Wiping the sensors w ill resolve
this problem.)
● The sensor is frozen. (Thawing the area will resolve this probl em.)
In especially cold weather, if a sensor is frozen, the screen m ay show an
abnormal display, or obstacles may not be detected.
● The sensor is covered in any way.
● In harsh sunlight or intense cold weather
● On an extremely bumpy road, on an incline, on gravel, or on grass
● The vicinity of the vehicle is noisy due to vehicle horns, moto rcycle
engines, air brakes of large vehicles, or other loud noises pro ducing ultra-
sonic waves.
● The sensor is splashed with water or drenched with heavy rain.
● The sensor is drenched with water on a flooded road.
● The vehicle is leaning considerably to one side.
● The vehicle is equipped with a fender pole or wireless antenna.
● The vehicle is approaching a tall or curved curb.
● The area directly under the bumpers is not detected.
● If obstacles draw too close to the sensor.
● The bumper or sensor receives a strong impact.
● A non-genuine Toyota suspension (lowered suspension etc.) is installed.
● There is another vehicle equipped with parking assist sensors in the vicin-
ity.
● Towing eyelets are installed.
● A backlit license plate is installed.
In addition to the examples above, depending on the shape and condition of
obstacles, detection may not be possible, or the detection range may be
shortened.

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PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
5
Driving
Parking Suppor t Brake function
The system operates in the follo wing situations when an obstacle is
detected in the traveling d irection of the vehicle.
◆The vehicle is driven at low speeds and the brake pedal is not
depressed, or is depressed too late
◆The accelerator pedal is depressed too far
: If equipped
When a collision may occur with an obstacle while parking or
traveling at low speeds, when the vehicle suddenly moves for-
ward due to mistaken accelerator pedal operation, or when the
vehicle moves due to the wrong shift position being selected,
the sensors detect obstacles to the front or rear in the travel ing
direction of the vehicle, and the system operates to lessen
impact with obstacles such as walls, and reduce resulting dam-
age.
Examples of system operation