2010 TOYOTA PRIUS sensor

226 2-4. Using other driving systems
PRIUS_U (OM47668U) U.S.A.
■Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following sit-
uations:
● Actual vehicle speed is more than approximately 10 mph (16 km/h)
below the set vehicle speed. 
At this time, the memorized set speed is not retained.
● Vehicle speed falls below 25 mph (40 km/h).
● Enhanced VSC is activated.
■ Vehicle-to-vehicle distance settings
Select a distance from the table below. Note that the distances shown corre-
spond to a vehicle speed of 50 mph (80 km/h). Vehicle-to-vehicle distance
increases/decreases in accordance with vehicle speed.
■ Radar sensor and grille cover
■ Warning lights, messages and buzze rs for dynamic radar cruise con-
trol
Warning lights, messages and buzzers are used to indicate a system mal-
function or to inform the driver of the need for caution while driving. 
( P. 508)
Distance optionsVehicle-to-vehicle distance
Long Approximately 160 ft. (50 m)
Medium Approximately 130 ft. (40 m)
Short Approximately 100 ft. (30 m)
Always keep the sensor and grille cover
clean to ensure that the vehicle-to-vehi-
cle distance control operates properly.
(Some obstructions, such as snow, ice
and plastic objects, cannot be detected
by the obstruction sensor.)
Dynamic radar cruise control is can-
celed if an obstruction is detected.
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PRIUS_U (OM47668U) U.S.A.
CAUTION
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate speed control and could cause an acci-
dent resulting in death or serious injury.
● In heavy traffic
● On roads with sharp bends
● On winding roads
● On slippery roads, such as those covered with rain, ice and snow
● On steep downhills, or where there are sudden changes between sharp up
and down gradients 
Vehicle speed may exceed the set speed when driving down a steep hill.
● At entrances to expressways
● When weather conditions are bad enough that they may prevent the sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
● When an approach warning buzzer can be heard often
■ When the sensor may not be corr ectly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles
are in front of you. 
As the sensor may not be able to correctly detect these types of vehicles,
the approach warning ( P. 227) will not be activated, and a fatal or serious
accident may result.
● Vehicles that cut in suddenly
● Vehicles traveling at low speeds
● Vehicles that are not moving
● Vehicles with small rear ends (trailers with no load on board etc.)
● Motorcycles traveling in the same lane

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PRIUS_U (OM47668U) U.S.A.
CAUTION
■Conditions under which the vehicle -to-vehicle distance control may
not function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor may not be able to correctly detect vehicles ahead, and a fatal or serious
accident may result:
● When water or snow thrown up by the surrounding vehicles hinders the
functioning of the sensor
● When your vehicle is pointing upwards (caused by a heavy load in the lug-
gage compartment etc.)
● When the road curves or when the lanes are narrow
● When steering wheel operation or your position in the lane is unstable
● When the vehicle ahead of you decelerates suddenly
■ Handling the radar sensor
Observe the following to ensure the cruise control system can function effec-
tively. 
Otherwise, the system may not function correctly and could result in an acci-
dent.
● Keep the sensor and front grille cover clean at all times. 
Clean the sensor and front grille cover with a soft cloth so you do not mark
or damage them.
● Do not subject the sensor or surrounding area to a strong impact . 
If the sensor moves even slightly off position, the system may malfunction.
If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by a Toyota dealer.
● Do not disassemble the sensor.
● Do not attach accessories or stickers to the sensor, grille cover or sur-
rounding area.
● Do not modify or paint the sensor and grille cover.
● Do not replace them with non-genuine parts.

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PRIUS_U (OM47668U) U.S.A.
LKA (Lane-Keeping Assist)
: If equipped
While driving on a freeway or motor highway that has lane markings,
this system recognizes the lanes using a camera as a sensor to
assist the driver with staying in the lane. The LKA system has two
functions.
■ Lane departure warning function
If the system judges that the vehicle may deviate from its lane, it
alerts the driver using rapid be eping, indications on the multi-
information display, and a sensory warning
* given via the steer-
ing wheel.
*: A slight steering torque is applied for a short period of time in
the direction of the center of the lane.
■ Lane keeping assist function
This function will be active when the vehicle-to-vehicle distance
control mode of the cruise control ( P. 218) is set with vehicle
speed above approx. 50 mph (approx. 75 km/h) and while the
lane departure warning function is active. When the lane keep-
ing assist function is active, a slight steering torque will be
applied, to help the driver mainta in the vehicle inside the lane.

240 2-4. Using other driving systems
PRIUS_U (OM47668U) U.S.A.
■No-handed driving warning
If the steering wheel is not operated for about 15 seconds on a straight road
or about 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 driv-
ing.
■ When the vehicle has been parked in the sun
The LKA system functions may not be available for a while after driving has
started. In such cases, turn the LKA system off and turn it on again after nor-
mal temperature returns. When the temperature in the cabin decreases and
the temperature around the camera sensor becomes suitable for its opera-
tion, the functions will begin to operate.
CAUTION
■Before using the LKA system
Do not rely on the LKA system to remain within a selected lane. The LKA
system is not designed to enable inattentive driving. The steering wheel
should be operated by the driver to mainta in the vehicle in a suitable position
within its lane. Always drive carefully.

242 2-4. Using other driving systems
PRIUS_U (OM47668U) U.S.A.
NOTICE
■Camera sensor
● Keep the windshield clean at all times. 
LKA performance may deteriorate due to the presence of raindrops, con-
densation, ice or snow on the windshield.
● Do not subject the camera sensor to strong impact or force, and do not
disassemble the camera sensor.
● Do not change the installation position of the camera sensor or remove it.
The direction of the camera sensor is precisely adjusted.
● When it is cold, using the heater with air blowing to the feet may allow the
upper part of the windshield to fog up. This will have a negative effect on
the images. In such a case, use the windshield defogger to provide warm,
dry air to the windshield.
● Do not place anything on the dashboard. 
The camera sensor may recognize the image reflected on the windshield
as lane markings by mistake.
● Do not scratch the camera lens, or let it get dirty.
● Do not attach a sticker or other items to the windshield near the camera
sensor.
Observe the following to ensure that the
LKA system functions correctly.
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PRIUS_U (OM47668U) U.S.A.
Pre-Collision System
: If equipped
Safety systems such as the brakes and seat belts are automati-
cally engaged to lessen impact and in juries to occupants as well as
vehicle damage when the radar sensor detects an unavoidable
frontal collision.
■ Pre-collision seat belts
If the pre-collision s ensor detects that a co llision is unavoidable,
the pre-collision system will retract the seat belt before the colli-
sion occurs. 
The same will happen if the driver makes an emergency braking
or loses control of the vehicle. ( P. 8 6 )
■ Pre-collision brake assist
When there is a high possibility of a frontal collision, the system
applies greater braking force in relation to how strongly the
brake pedal is depressed.
■ Pre-collision braking
When there is a high possibility of a frontal collision, the system
warns the driver using a warning light, warning display and
buzzer. If the system determines that a collision is unavoidable,
the brakes are auto matically applied to reduce the collision
speed. Pre-collision braking can be disabled using the pre-colli-
sion braking off button.

250 2-4. Using other driving systems
PRIUS_U (OM47668U) U.S.A.
Disabling pre-collision brakingEnabled
Disabled
The “PCS” warning light comes
on when the pre-collision braking
is disabled.
Radar sensorDetects vehicles or other obsta-
cles on or near the road ahead
and determines whether a colli-
sion is imminent based on the
position, speed, and heading of
the obstacles.
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