2012 TOYOTA PRIUS PLUS sensor

290 2-4. Using other driving systems
PRIUS +_OM_OM47821E_(EE)
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 16 km/h (10 mph)
below the set vehicle speed.
At this time, the memorized set speed is not retained.
Vehicle speed falls below approximately 40 km/h (25 mph).
VSC is activated.
Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-
vehicle distance control operates properly. (Some obstructions, such as
snow, ice and plastic objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control (vehicle-to-vehicle distance control mode) will
be canceled if dirt is detected. (Constant speed control mode can be used).
Grille cover
Radar sensor

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When driving
PRIUS +_OM_OM47821E_(EE)
Warning lights, warning code and buzzers for dynamic radar cruise
control
Warning lights, warning code and buzzers are used to indicate a system
malfunction or to inform the driver of the need for caution while driving.
The warning codes displayed on the meter indicate the following situations.
Fix each problem in accordance with the correction procedure, and check
that the system is operating normally.
If the warning code persists even after fixing, have the vehicle inspected by
any authorized Toyota dealer or repairer, or another duly qualified and
equipped professional.
Warning code/
warning lightDetailsCorrection procedure
(yellow)Indicates that the radar
cruise control sensor is
dirty or covered with
ice.Clean the sensor.
(yellow)Indicates that the radar
cruise control system is
unable to judge vehi-
cle-to-vehicle distance.If the windshield wip-
ers are on, turn them
off or set them to either
the intermittent or the
slow mode.
(yellow)Indicates a malfunction
in the radar cruise con-
trol system.Press the “ON-OFF”
button once to deacti-
vate the system, and
then press the button
again to reactivate the
system.

296 2-4. Using other driving systems
PRIUS +_OM_OM47821E_(EE)
CAUTION
When the sensor may not be correctly 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. 287) 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
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

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When driving
PRIUS +_OM_OM47821E_(EE)
CAUTION
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 grille cover clean at all times.
Clean the sensor and 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 become
inaccurate or malfunction. If the sensor or surrounding area is subject to a
strong impact, always have the area inspected and adjusted by any autho-
rized Toyota dealer or repairer, or another duly qualified and equipped pro-
fessional.
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.

307
2-4. Using other driving systems
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When driving
PRIUS +_OM_OM47821E_(EE)
PCS (Pre-Crash Safety System)
: If equipped
When the radar sensor detects possibility of a frontal collision, the
pre-crash safety systems such as the brakes and seat belts are auto-
matically engaged to lessen impact to occupants as well as vehicle
damage.
Pre-crash seat belts (front seat belts only)
If the pre-crash sensor detects that a collision is unavoidable, the pre-
crash safety system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. (P. 124)
However, when the VSC system is disabled, the system will not oper-
ate in the event of skidding.
Pre-crash 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-crash 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 sys-
tem determines that a collision is unavoidable, the brakes are automat-
ically applied to reduce the collision speed. Pre-crash braking can be
disabled using the pre-crash braking off switch.

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PRIUS +_OM_OM47821E_(EE)
Disabling pre-crash braking
Pre-crash braking enabled
Pre-crash braking disabled
The “PCS” warning light will
turn on when pre-crash brak-
ing is disabled.
Radar sensor
The radar sensor detects vehi-
cles or other obstacles on or
near the road ahead and deter-
mines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles.

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PRIUS +_OM_OM47821E_(EE)
Conditions that may trigger the system even if there is no possibility of
a collision
When there is an object by the roadside at the entrance to a curve
When passing an oncoming vehicle on a curve
When driving over a narrow iron bridge
When there is a metal object on the road surface
When driving on an uneven road surface (nose up, nose down)
When passing an oncoming vehicle on a left-turn (left-hand drive vehi-
cles) or right-turn (right-hand drive vehicles)
When your vehicle rapidly closes on the vehicle in front
When a grade separation/interchange, sign, billboard, or other structure
appears to be directly in the vehicle’s line of travel
When the steep angle of the road causes a metal object located beneath
the road surface to be seen ahead of the vehicle
When an extreme change in vehicle height occurs
When the axis of the radar is out of adjustment
When passing through certain toll gates
When passing through an overpass
When the system is activated in the situations described above, there is also
a possibility that the seat belts will retract quickly and the brakes will be
applied with a force greater than normal. When the seat belt is locked in the
retracted position, stop the vehicle in a safe place, release the seat belt and
refasten it.
Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may
also be occasions when the sensor cannot detect pedestrians, animals,
bicycles, motorcycles, trees, or snowdrifts.

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When driving
PRIUS +_OM_OM47821E_(EE)
Situations in which the pre-crash safety system does not function
properly
The system may not function effectively in situations such as the following:
On roads with sharp bends or uneven surfaces
If a vehicle suddenly moves in front of your vehicle, such as at an inter-
section
If a vehicle suddenly cuts in front of your vehicle, such as when overtak-
ing
In inclement weather such as heavy rain, fog, snow or sand storms
When your vehicle is skidding with the VSC system off
When an extreme change in vehicle height occurs
When the axis of the radar is out of adjustment
Automatic cancelation of the pre-crash safety system
When a malfunction occurs due to sensor contamination, etc. that results in
the sensors being unable to detect obstacles, the pre-crash safety system
will be automatically disabled. In this case, the system will not activate even
if there is a collision possibility.
When there is a malfunction in the system, or if the system is tempo-
rarily unusable
Warning lights will turn on or flash. (P. 472, 476)