TOYOTA PRIUS 2019 Owners Manual (in English)

291
PRIUS_OM_OM47C35U_(U)
4-5. Using the driving support systems
4
Driving
PCS (Pre-Collision System)
◆Pre-collision warning
When the system determines
that the possibility of a frontal
collision is high, a buzzer will
sound and a warning message
will be displayed on the multi-
information display to urge the
driver to take evasive action.
: If equipped
The pre-collision system uses a radar sensor and camera sen-
sor to detect vehicles and pedest rians in front of your vehicle.
When the system determines that t he possibility of a frontal col-
lision with a vehicle or pedest rian is high, a warning operates to
urge the driver to take evasive action and the potential brake
pressure is increased to help the driver avoid the collision. If the
system determines that the possi bility of a frontal collision with
a vehicle or pedestrian is extremely high, the brakes are auto-
matically applied to help avoid the collision or help reduce th e
impact of the collision.
The pre-collision system can b e disabled/enabled and the warnin g
timing can be changed. ( P. 2 9 5 )

292
PRIUS_OM_OM47C35U_(U)
4-5. Using the driving support systems
◆Pre-collision brake assist
When the system determines that the possibility of a frontal colli-
sion is high, the system applies greater braking force in relat ion to
how strongly the brake pedal is depressed.
◆Pre-collision braking
When the system determines that the possibility of a frontal colli-
sion is high, the system warns the driver. If the system determ ines
that the possibility of a frontal collision is extremely high, the brakes
are automatically applied to hel p avoid the collision or reduce the
collision speed.

PRIUS_OM_OM47C35U_(U)
2934-5. Using the driving support systems
4
Driving
WARNING
■Limitations of the pre-collision system
● The driver is solely responsible for safe driving. Always drive safely, taking
care to observe your surroundings.
Do not use the pre-collision system instead of normal braking o perations
under any circumstances. This system will not prevent collision s or lessen
collision damage or injury in every situation. Do not overly re ly on this sys-
tem. Failure to do so may lead to an accident, resulting in dea th or serious
injury.
● Although this system is designed to help avoid a collision or h elp reduce
the impact of the collision, its effectiveness may change according to vari-
ous conditions, therefore the system may not always be able to achieve
the same level of performance.
Read the following conditions carefully. Do not overly rely on this system
and always drive carefully.
• Conditions under which the system may operate even if there is no pos- sibility of a collision: P. 297
• Conditions under which the system may not operate properly: P. 299
● Do not attempt to test the operation of the pre-collision syste m yourself.
Depending on the objects used for testing (dummies, cardboard o bjects
imitating detectable objects, etc.), the system may not operate properly,
possibly leading to an accident.
■ Pre-collision braking
● When the pre-collision braking function is operating, a large a mount of
braking force will be applied.
● If the vehicle is stopped by the operation of the pre-collision braking func-
tion, the pre-collision braking function operation will be canceled after
approximately 2 seconds. Depress the brake pedal as necessary.
● The pre-collision braking function may not operate if certain operations are
performed by the driver. If the accelerator pedal is being depressed
strongly or the steering wheel is being turned, the system may determine
that the driver is taking evasive action and possibly prevent the pre-colli-
sion braking function from operating.
● In some situations, while the pre-collision braking function is operating,
operation of the function may be canceled if the accelerator pedal is
depressed strongly or the steering wheel is turned and the syst em deter-
mines that the driver is taking evasive action.
● If the brake pedal is being depressed, the system may determine that the
driver is taking evasive action and possibly delay the operation timing of
the pre-collision braking function.

294
PRIUS_OM_OM47C35U_(U)
4-5. Using the driving support systems
WARNING
■When to disable the pre-collision system
In the following situations, disable the system, as it may not operate prop-
erly, possibly leading to an accident resulting in death or serious injury:
● When the vehicle is being towed
● When your vehicle is towing another vehicle
● When transporting the vehicle via truck, boat, train or similar means of
transportation
● When the vehicle is raised on a lift with the hybrid system operating and
the tires are allowed to rotate freely
● When inspecting the vehicle using a drum tester such as a chass is dyna-
mometer or speedometer tester, or when using an on vehicle whee l bal-
ancer
● When a strong impact is applied to the front bumper or front gr ille, due to
an accident or other reasons
● If the vehicle cannot be driven in a stable manner, such as when the vehi-
cle has been in an accident or is malfunctioning
● When the vehicle is driven in a sporty manner or off-road
● When the tires are not properly inflated
● When the tires are very worn
● When tires of a size other than specified are installed
● When tire chains are installed
● When a compact spare tire or an emergency tire puncture repair kit is used
● If equipment (snow plow, etc.) that may obstruct the radar sens or or cam-
era sensor is temporarily installed to the vehicle

PRIUS_OM_OM47C35U_(U)
2954-5. Using the driving support systems
4
Driving
■Enabling/disabling th e pre-collision system
The pre-collision system can be enabled/disabled on the
screen ( P. 149) of the multi-information display.
The system is automatically enabled each time the power switch is
turned to ON mode.
If the system is disabled, the
PCS warning light will turn on.
■Changing the pre-colli sion warning timing
The pre-collision warning timing can be changed on the
screen ( P. 149) of the multi-in formation display.
The operation timing setting is retained when the power switch is turned
off.
Far
The warning will begin to oper-
ate earlier than with the default
timing.
Middle
This is the default setting.
Near
The warning will begin to oper-
ate later than with the default
timing.
Changing settings of the pre-collision system
1
2
3

296
PRIUS_OM_OM47C35U_(U)
4-5. Using the driving support systems
■Operational conditions
The pre-collision system is enabled and the system determines that the pos-
sibility of a frontal collision with a vehicle or pedestrian is high.
Each function is operational at the following speeds:
● Pre-collision warning:
• Vehicle speed is between approximately 7 and 110 mph (10 and 1 80 km/h).
(For detecting a pedestrian, vehicle speed is between approximately 7 and
50 mph [10 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or ped estrian
ahead is approximately 7 mph (10 km/h) or more.
● Pre-collision brake assist:
• Vehicle speed is between approximately 20 and 110 mph (30 and 180 km/h).
(For detecting a pedestrian, vehicle speed is between approxima tely 20 and
50 mph [30 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or ped estrian
ahead is approximately 20 mph (30 km/h) or more.
● Pre-collision braking:
• Vehicle speed is between approximately 7 and 110 mph (10 and 1 80 km/h).
(For detecting a pedestrian, vehicle speed is between approximately 7 and
50 mph [10 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or ped estrian
ahead is approximately 7 mph (10 km/h) or more.
The system may not operate in the following situations:
● If a 12-volt battery terminal has been disconnected and reconnected and
then the vehicle has not been driven for a certain amount of ti me
● If the shift position is in R
● If VSC is disabled (only the pre-collision warning function wil l be opera-
tional)
■ Pedestrian detection function
■ Cancelation of the pre-collision braking
If either of the following occur while the pre-collision brakin g function is oper-
ating, it will be canceled:
● The accelerator pedal is depressed strongly.
● The steering wheel is turned sharply or abruptly.
The pre-collision system detects pedestri-
ans based on the size, profile, and motion
of a detected object. However, a pedes-
trian may not be detected depending on
the surrounding brightness and the
motion, posture, and angle of the
detected object, preventing the system
from operating properly. (P. 301)

PRIUS_OM_OM47C35U_(U)
2974-5. Using the driving support systems
4
Driving
■Conditions under which the system may operate even if there is no pos-
sibility of a collision
● In some situations such as the following, the system may determ ine that
there is a possibility of a frontal collision and operate.
• When passing a vehicle or pedestrian
• When changing lanes while overtaking a preceding vehicle
• When overtaking a preceding vehicle that is changing lanes
• When rapidly closing on a vehicle ahead
• If the front of the vehicle is raised or lowered, such as when the road sur-
face is uneven or undulating
• When approaching objects on the roadside, such as guardrails, utility
poles, trees, or walls
• When overtaking a preceding vehicle
that is making a left/right turn
• When passing a vehicle in an oncom- ing lane that is stopped to make a
right/left turn
• When driving on a road where relative location to vehicle ahead in an adja-
cent lane may change, such as on a
winding road
• When there is a vehicle, pedestrian, or object by the roadside at the
entrance of a curve

298
PRIUS_OM_OM47C35U_(U)
4-5. Using the driving support systems
• When driving on a narrow path surrounded by a structure, such as in a
tunnel or on an iron bridge
• When there is a metal object (manhole cover, steel plate, etc. ), steps, or a
protrusion on the road surface or roadside
• When rapidly closing on an electric toll gate barrier, parking area barrier, or other barrier that opens and closes
• When using an automatic car wash
• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When there are patterns or paint on the road or a wall that may be mis-
taken for a vehicle or pedestrian
• When driving near an object that reflects radio waves, such as a large
truck or guardrail
• When a crossing pedestrian
approaches very close to the vehicle
• When passing through a place with a low structure above the road (low ceil-
ing, traffic sign, etc.)
• When passing under an object (bill- board, etc.) at the top of an uphill road
• When driving through or under objects that may contact the vehicle,
such as thick grass, tree branches, or
a banner

PRIUS_OM_OM47C35U_(U)
2994-5. Using the driving support systems
4
Driving
• 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, a vehicle may not be detected by
the radar sensor and camera sensor, preventing the system from operating
properly:
• If an oncoming vehicle is approaching your vehicle
• If a vehicle ahead is a motorcycle or bicycle
• When approaching the side or front of a vehicle
• If a preceding vehicle has a small rear end, such as an unload ed 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 ahe ad
• If a vehicle cuts in front of your vehicle or emerges from bes ide a vehicle
• If a vehicle ahead makes an abrupt maneuver (such as sudden sw erving,
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
• When a vehicle ahead is not directly in front of your vehicle

300
PRIUS_OM_OM47C35U_(U)
4-5. Using the driving support systems
• When driving in inclement weather such as heavy rain, fog, snow or a
sandstorm
• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When driving in a place where the surrounding brightness changes sud- denly, such as at the entrance or exit of a tunnel
• When a very bright light, such as the sun or the headlights of oncoming
traffic, shines directly into the camera sensor
• When the surrounding area is dim, such as at dawn or dusk, or while at
night or in a tunnel
• After the hybrid system has started the vehicle has not been d riven for a
certain amount of time
• While making a left/right turn and for a few seconds after mak ing a left/
right turn
• While driving on a curve and for a few seconds after driving o n a curve
• If your vehicle is skidding
• If the wheels are misaligned
• If a wiper blade is blocking the camera sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or camera sensor 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 the front of the vehicle is raised or
lowered