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4155-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
■Automatic cancelation of constant speed control mode
Constant speed control mode is automatically canceled in the following situa-
tions:
●Actual vehicle speed is more than approximately 16 km/h (10 mph) below
the set vehicle speed.
●Actual vehicle speed falls below approximately 30 km/h (20 mph).
●VSC is activated.
●TRC is activated for a period of time.
●When the VSC or TRC system is turned off.
●When the brake control or output restriction control of a driving support sys-
tem operates.
(For example: Pre-Collision System, Drive-Start Control)
If constant speed control mode is automatically canceled for any reasons
other than the above, there may be a malfunction in the system. Contact any
authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
■The Dynamic Radar Cruise Control with Road Sign Assist may not oper-
ate properly when
As the Dynamic Radar Cruise Control with Road Sign Assist may not oper-
ate properly in conditions in which RSA may not operate or detect correctly
(P. 399), when using this function, make sure to check the speed limit
sign displayed.
In the following situations, the set speed may not be changed to the recog-
nized speed limit by pushing the lever up or down.
●If speed limit information is not available
●When the recognized speed limit is the same as the set speed
●When the recognized speed limit is outside of the speed range that the
dynamic radar cruise control system can operate
■Brake operation
A brake operation sound may be heard and the brake pedal response may
change, but these are not malfunctions.
■Warning messages and buzzers for dynamic 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. (P. 366, 667)
Page 418 of 818
4165-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
■When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate 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 of vehicles, the
approach warning (P. 411) 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
Page 419 of 818
4175-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
■Conditions under which the vehicle-to-vehicle distance control mode
may not function correctly
In the case of the following conditions, operate the brake pedal (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 the 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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4225-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
■Automatic speed limiter cancellation
The set speed is automatically canceled in any of the situations:
● Cruise control is activated.
● When the VSC system and/or TRC system is turned off by pressing the
VSC OFF switch.
■ If the “Speed Limiter Malfunction Visit Your Dealer” is displayed on the
multi-information display
Stop in a safe location, turn the power switch off and back on again, and then
set the speed limiter. If the speed limiter cannot be set, the system may be
malfunctioning. Even though the vehicle can be driven normally, have the
vehicle inspected by any authorized Toyota retailer or Toyota authorized
repairer, or any reliable repairer.
WARNING
■ To avoid operating the speed limiter by mistake
Keep the speed limiter switch off when not in use.
■ Situations unsuitable for speed limiter
Do not use the speed limiter in either of the following situations.
Doing so may result in control of the vehicle being lost and could cause a
serious or fatal accident.
● On slippery roads, such as those covered with rain, ice or snow
● On steep hills
NOTICE
When a warning is issued using the meter display and buzzer after exceed-
ing the set speed limit on a steep decline, depress the brake pedal to decel-
erate.
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4585-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
●When vehicle horns, vehicle detectors, motorcycle engines, air brakes of
large vehicles, the clearance sonar of other vehicles or other devices which
produce ultrasonic waves are near the vehicle
●A sensor is coated with a sheet of spray or heavy rain.
●If objects draw too close to the sensor.
●When a pedestrian is wearing clothing that does not reflect ultrasonic waves
(ex. skirts with gathers or frills).
●When objects that are not perpendicular to the ground, not perpendicular to
the vehicle traveling direction, uneven, or waving are in the detection range.
●Strong wind is blowing
●When driving in inclement weather such as fog, snow or a sandstorm
●When an object that cannot be detected is between the vehicle and a
detected object
●If an object such as a vehicle, motorcycle, bicycle or pedestrian cuts in front
of the vehicle or runs out from the side of the vehicle
●If the orientation of a sensor has been changed due to a collision or other
impact
●When equipment that may obstruct a sensor is installed, such as a towing
eyelet, bumper protector (an additional trim strip, etc.), bicycle carrier, or
snow plow
●If the front of the vehicle is raised or lowered due to the carried load
●If the vehicle cannot be driven in a stable manner, such as when the vehicle
has been in an accident or is malfunctioning
●When tire chains, a compact spare tire or an emergency tire puncture repair
kit are used.
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4595-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
■Situations in which the system may operate even if there is no possibil-
ity of a collision
In some situations, such as the following, the system may operate even
though there is no possibility of a collision.
● When driving toward a banner, flag, low-hanging branch or boom barrier
(such as those used at railroad crossings, toll gates and parking lots)
● When there is a rut or hole in the surface of the road
● When driving on a metal cover (grating), such as those used for drainage
ditches
● When driving up or down a steep slope
● If a sensor is hit by a large amount of water, such as when driving on a
flooded road
● There is dirt, snow, water drops or ice on a sensor. (Cleaning the sensors
will resolve this problem.)
● A sensor is coated with a sheet of spray or heavy rain
● When driving in inclement weather such as fog, snow or a sandstorm
● When vehicle horns, vehicle detectors, motorcycle engines, air brakes of
large vehicles, the clearance sonar of ot her vehicles or other devices which
produce ultrasonic waves are near the vehicle
● If the front of the vehicle is raised or lowered due to the carried load
● If the orientation of a sensor has been changed due to a collision or other
impact
● Driving close to columns (H-shaped steel beams, etc.) in multi-story parking
garages, construction sites, etc.
● If the vehicle cannot be driven in a stable manner, such as when the vehicle
has been in an accident or is malfunctioning
● When driving on a narrow road
● When strong winds are blowing
Page 464 of 818
4625-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
Parking Support Brake function
The system operates in the following situations when an obstacle is
detected in the traveling direction 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 traveling
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
Page 466 of 818
4645-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
Front corner sensors
Front center sensors
Rear corner sensors
Rear center sensors
The Parking Support Brake function can be enabled/disabled on the
screen ( P. 247) of the multi-information display.
When the Parking Support Brake
function is off, the PKSB OFF indi-
cator illuminates.
When the Parking Support Brake function is switched off, system operation
does not resume until the function is switched back on through the
screen on the multi-information display. (System operation does not
resume by operating the power switch.)
Types of sensors
1
2
3
4
Changing settings of the Parking Support Brake function