Page 233 of 596
2334-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52J11U)• If the front of the vehicle is raised or lowered, such as when the road sur-
face is uneven or undulating
• When driving on a narrow path surrounded by a structure, such as in a tunnel or on an iron bridge
• When passing extremely close to a
vehicle or structural object
• When there is a vehicle or object by the roadside at the entrance of a
curve
• When there is a reflective object (manhole cover, steel plate, etc.),
steps, dip, or a protrusion on the road
surface or roadside
• When passing through a place with a low structure above the road (low ceil-
ing, traffic sign, etc.)
• When there is a structural object (overpass, traffic sign, billboard,
street light, etc.) at the top of an uphill
road
Page 234 of 596
2344-5. Using the driving support systems
PRIUS c_U (OM52J11U)• When using an automatic car wash
• When there are patterns or paint on the road or a wall that may be mis-
taken for a vehicle
• When rapidly closing on an electric
toll gate barrier, parking area barrier,
or other barrier that opens and closes
• When approaching a low hanging object that may contact the vehicle,
such as a banner, tree branches or
thick grass
• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When the front part of the vehicle is raised or lowered
Page 235 of 596
2354-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52J11U)• When the sensor is misaligned due to
a strong impact being applied to the
sensor, etc.
• When the vehicle is being parked in a place where there is a low hanging
object at the height of the front sensor
• When the windshield is covered with raindrops, etc.
Page 236 of 596

2364-5. Using the driving support systems
PRIUS c_U (OM52J11U)■
Situations in which the system may not operate properly
●In some situations such as the following, a vehicle may not be detected by
the front sensor, preventing the system from operating properly:
• If an oncoming vehicle is approaching your vehicle
• When approaching the side or front of a vehicle
• If a preceding vehicle has a small rear end, such as an unloaded truck
• If a vehicle ahead is carrying a load which protrudes past its rear bumper
• If a vehicle ahead is irregularly shaped, such as a tractor or side car
• If the sun or other light is shining directly on a vehicle ahead
• If a vehicle ahead makes an abrupt maneuver (such as sudden swerving,
acceleration or deceleration)
• When suddenly cutting behind a preceding vehicle • If a preceding vehicle has a low rear end, such as a low bed trailer
• If a vehicle ahead has extremely high ground clearance
• If a vehicle cuts in front of your vehicle or emerges from beside a vehicle
Page 237 of 596
2374-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52J11U)• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke that may obscure vehicles ahead
• When driving in a place where the surrounding brightness changes sud-
denly, such as at the entrance or exit of a tunnel
• While driving on a curve and for a certain amount of time after driving on a curve
• When a vehicle ahead is not directly
in front of your vehicle
• When driving in inclement weather such as heavy rain, fog, snow or a
sand storm
• When a very bright light, such as the sun or the headlights of oncoming
traffic, shines directly into the front
sensor
• When the surrounding area is dim, such as at dawn or dusk, or while at
night or in a tunnel
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2384-5. Using the driving support systems
PRIUS c_U (OM52J11U)• If the wheels are misaligned
• If a wiper blade is blocking the front sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on roads with sharp bends or uneven surfaces
• When a preceding vehicle is a poor reflector of laser
● In some situations such as the following, sufficient braking force 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 slippery sur- face
• If your vehicle is skidding
• When the front part of the vehicle is
raised or lowered
• When the sensor is misaligned due to a strong impact being applied to the
sensor, etc.
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2394-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52J11U)■
If the PCS warning light flashes a nd a warning message is displayed on
the multi-information display
The pre-collision system may be tem porarily unavailable or there may be a
malfunction in the system.
● In the following situations, the warning light will turn off, the message will
disappear and the system will become operational when normal operating
conditions return:
• When the area around the front sensor is hot, such as in the sun
• When the windshield is fogged up or covered with condensation or ice
(→ P. 376)
• When the front sensor or the area around either sensor is cold, such as in an extremely cold environment
• If the area in front of the front sensor is obstructed, such as when the hood is open
● If the PCS warning light continues to flash or the warning message does not
disappear, the system may be malfunctioning. Have the vehicle inspected
by your Toyota dealer immediately.
■ If VSC is disabled
●If TRAC and VSC are disabled ( →P. 265), the pre-collision brake assist and
pre-collision braking functions are also disabled. However, the pre-collision
warning function will still operate.
● The PCS warning light illuminates and “VSC TURNED OFF PRE-COLLI-
SION BRAKE SYSTEM UNAVAILABLE” is displayed on the multi-informa-
tion display.
Page 240 of 596
2404-5. Using the driving support systems
PRIUS c_U (OM52J11U)
When driving on roads with white (yello w) lines, this function alerts the
driver when the vehicle might depart from its lane.
The LDA system recognizes visi-
ble white (yellow) lines with the
front sensor on the upper portion
of the front windshield.
When the system determines that
the vehicle might depart from its
lane, a warning is displayed on
the multi-information display and
the warning buzzer sounds to
alert the driver.
When the warning buzzer sounds,
check the surrounding road situa-
tion and carefully operate the
steering wheel to move the vehicle
back to the center within the white
(yellow) lines.
LDA (Lane Depa rture Alert)∗
∗: If equipped
Summary of function
Lane departure alert function