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Driving
Two types of sensors, located behind the front grille and winds hield,
detect information necessary to operate the drive assist systems.
Radar sensor
Front camera
Sensors
1
2
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WARNING
■To avoid malfunction of the radar sensor
Observe the following precautions.
Otherwise, the radar sensor may not operate properly, possibly leading to
an accident resulting in death or serious injury.
● Keep the radar sensor and the radar sensor cover clean at all times.
● Do not attach accessories, stickers (including transparent stic kers) or
other items to the radar sensor, radar sensor cover or surrounding area.
● Do not subject the radar sensor or its surrounding area to a st rong impact.
If the radar sensor, front grille, or front bumper has been sub jected to a
strong impact, have the vehicle inspected by your Toyota dealer.
● Do not disassemble the radar sensor.
● Do not modify or paint the radar sensor or radar sensor cover.
● In the following cases, the radar sensor must be recalibrated. Contact your
Toyota dealer for details.
• When the radar sensor or front grille are removed and installe d, or
replaced
• When the front bumper is replaced
Radar sensor
Radar sensor cover
If the front of the radar sensor or the
front or back of the radar sensor cover
is dirty or covered with water droplets,
snow, etc., clean it.
Clean the radar sensor and radar sen-
sor cover with a soft cloth to avoid
damaging them.
1
2
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Driving
■If a warning message is displayed on the multi-information disp lay
A system may be temporarily unavailable or there may be a malfu nction in
the system.
● In the following situations, perform the actions specified in t he table. When
the normal operating conditions are detected, the message will disappear
and the system will become operational.
If the message does not disappear, contact your Toyota dealer.
SituationActions
When the area around a cam-
era is covered with dirt, mois-
ture (fogged up, covered with
condensation, ice, etc.), or
other foreign matter
Using the wiper and A/C function,
remove the dirt and other attached mat-
ter. ( P. 434, 444)
When the temperature around
the front camera is outside of
the operational range, such as
when the vehicle is in the sun or
in an extremely cold environ-
ment
If the front camera is hot, such as after
the vehicle had been parked in the sun,
use the air conditioning system to
decrease the temperature around the
front camera.
If a sunshade was used when the vehi-
cle was parked, depending on its type,
the sunlight reflected from the surface
of the sunshade may cause the tem-
perature of the front camera to become
excessively high.
If the front camera is cold, such after the
vehicle is parked in an extremely cold
environment, use the air conditioning
system to increase the temperature
around the front camera.
The area in front of the front
camera is obstructed, such as
when the hood is open or a
sticker is attached to the part of
the windshield in front of the
front camera.
Close the hood, remove the sticker, etc.
to clear the obstruction.
When “Pre-Collision System
Unavailable” is displayed.Check whether there is attached materi-
als on the radar sensor and radar sensor
cover, and if there is, remove it.
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●In the following situations, if the situation has changed (or the vehicle has
been driven for some time) and the normal operating conditions are
detected, the message will disappear and the system will become opera-
tional.
If the message does not disappear, contact your Toyota dealer. • When the temperature around the radar sensor is outside of the opera-
tional range, such as when the vehicle is in the sun or in an e xtremely
cold environment
• When the front camera cannot detect objects in front of the ve hicle, such
as when driving in the dark, snow, or fog, or when bright lights are shining
into the front camera
• Depending on the conditions in the vicinity of the vehicle, th e radar may
judge the surrounding environment can not be properly recognize d. In
that case, “Pre-Collision Syst em Unavailable” is displayed.
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Driving
PCS (Pre-Collision System)
The system can detect the following:
●Vehicles
● Bicyclists
● Pedestrians
: If equipped
The pre-collision system uses a radar sensor and front camera
to detect objects ( P. 291) in front of the vehicle. When the sys-
tem determines that the possibility of a frontal collision with an
object is high, a warning operates to urge the driver to take e va-
sive action and the potential brake pressure is increased to he lp
the driver avoid the collision. If the system determines that t he
possibility of a frontal collision with an object is extremely high,
the brakes are automatically applied to help avoid the collisio n
or help reduce the impa ct of the collision.
The pre-collision system can b e disabled/enabled and the warnin g
timing can be changed. ( P. 2 9 5 )
Detectable objects
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Driving
• When driving through steam or smoke
• When driving near an object that reflects radio waves, such as a large
truck or guardrail
• When driving near a TV tower, broadcasting station, electric power plant, or other location where strong radio waves or electrical noise may be
present
■ Situations in which the syst em may not operate properly
● In some situations such as the following, an object may not be detected by
the radar sensor and front camera, preventing the system from operating
properly:
• When a detectable object is approaching your vehicle
• When your vehicle or a detectable object is wobbling
• If a detectable object makes an abrupt maneuver (such as sudde n swerv-
ing, acceleration or deceleration)
• When your vehicle approaches a detectable object rapidly
• When a detectable object is near a wall, fence, guardrail, manhole cover, vehicle, steel plate on the road, etc.
• When a detectable object is under a structure
• When part of a detectable object is hidden by an object, such as large
baggage, an umbrella, or guardrail
• When multiple detectable objects are close together
• If the sun or other light is shining directly on a detectable object
• When a detectable object is a shade of white and looks extremely bright
• When a detectable object appears to be nearly the same color o r bright-
ness as its surroundings
• If a detectable object cuts or suddenly emerges in front of your vehicle
• When the front of your vehicle is hit by water, snow, dust, et c.
• When a very bright light ahead, such as the sun or the headlig hts of
oncoming traffic, shines directly into the front camera
• When approaching the side or front of a vehicle ahead
• If a vehicle ahead is a motorcycle • When driving through or under
objects that may contact your vehicle,
such as thick grass, tree branches, or
a banner
• When a detectable object is not directly in front of your vehicle
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Driving
• If the wheels are misaligned
• If a wiper blade is blocking the front camera
• The vehicle is being driven at extremely high speeds
• When driving on a hill
• If the radar sensor or front camera is misaligned
● In some situations such as the following, sufficient braking fo rce may not be
obtained, preventing the system from performing properly:
• If the braking functions cannot operate to their full extent, such as when
the brake parts are extremely cold, extremely hot, or wet
• If the vehicle is not properly maintained (brakes or tires are excessively
worn, improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other sli ppery sur-
face
■ If VSC is disabled
●If VSC is disabled ( P. 417), the pre-collision brake assist and pre-collision
braking functions are also disabled.
● The PCS warning light will turn on and “VSC Turned Off Pre-Coll ision Brake
System Unavailable” will be displayed on the multi-information display.
• If the front of the vehicle is raised or
lowered
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Driving
In the following situations, the RSA syst em will notify the driver.
● When the vehicle speed exceeds the speed notification threshold of
the speed limit sign displayed, the sign display will be emphas ized
and a buzzer will sound.
● When the RSA system recognizes a do not enter sign and deter-
mines that your vehicle has ent ered a no-entry area, the displayed
sign will flash and a buzzer will sound.
Depending on the situation, a not ification function may not operate
properly.
■ Setting procedure
P. 151
■ Automatic turn-off of RSA sign display
In the following situations, a displayed speed limit sign and/o r do not enter
sign will stop being displayed automatically:
● No sign has been recognized for a certain distance.
● The road changes due to a left or right turn, etc.
In the following situations, stop and yield signs will stop bei ng displayed auto-
matically:
● The system determines that your vehicle has passed the sign.
● The road changes due to a left or right turn, etc.
■ Conditions in which the function may not operate or detect correctly
In the following situations, RSA does not operate normally and may not rec-
ognize signs, display the incorrect sign, etc. However, this do es not indicate a
malfunction.
● The front camera is misaligned due to a strong impact being applied to the
sensor, etc.
● Dirt, snow, stickers, etc. are on the windshield near the front camera.
● In inclement weather such as heavy rain, fog, snow or sand storms
● Light from an oncoming vehicle, the sun, etc. enters the front camera.
● The sign is dirty, faded, tilted or bent.
● The contrast of electronic sign is low.
● All or part of the sign is hidden by the leaves of a tree, a pole, etc.
● The sign is only visible to the front camera for a short amount of time.
● The driving scene (turning, lane change, etc.) is judged incorr ectly.
● If a sign not appropriate for the currently traveled lane, but the sign exists
directly after a freeway branches, or in an adjacent lane just before merging.
● Stickers are attached to the rear of the preceding vehicle.
Notification function