Page 225 of 588

2254-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52F96U)
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 operations
under any circumstances. This system will not prevent collisions or lessen
collision damage or injury in every situation. Do not overly rely on this sys-
tem. Failure to do so may lead to an accident, resulting in death or serious
injury.
● Although this system is designed to help avoid and reduce the impact of a
collision, its effectiveness may change according to various 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. 229
• Conditions under which the system may not operate properly: P. 233
● Do not attempt to test the operation of the pre-collision system yourself, as
the system may not operate properly, possibly leading to an accident.
■ Pre-collision braking
●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 system deter-
mines that the driver is taking evasive action.
● A large amount of braking force is applied while the pre-collision braking
function is operating. Additionally, as the operation of the pre-collision
braking function will be canceled after the vehicle has been stopped for
approximately 2 seconds if it is stopped by the operation of the pre-colli-
sion braking function, the driver should depress the brake pedal as neces-
sary.
● 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.
Page 226 of 588

2264-5. Using the driving support systems
PRIUS c_U (OM52F96U)
WARNING
●While driving, such as when driving through a railway crossing, the system
may determine that the possibility of a collision with an object, such as rail-
way crossing barrier, is high and operate the pre-collision braking function.
To move the vehicle in an emergency, such as if the system operates in a
railway crossing, perform the following operations and then take the nec-
essary measures to ensure your safety.
• If the vehicle has been stopped, depress the accelerator pedal.
• If the vehicle is decelerating, fully depress the accelerator pedal.
(P. 228)
• Disable the pre-collision system. ( P. 227)
■ 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 on and the tires
are allowed to rotate freely
● When inspecting the vehicle using a drum tester such as a chassis dyna-
mometer or speedometer tester, or when using an on vehicle wheel bal-
ancer
● 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 condition of the tires is poor and they do not perform well
( P. 428, 439)
● 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
Page 227 of 588

2274-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52F96U)■
Enabling/disabling th
e pre-collision system
Press the PCS switch for 3 sec-
onds or more.
The PCS warning light will turn
on and a message will be dis-
played on the multi-information
display.
To enable the system, press the
PCS switch again.
The pre-collision system is
enabled each time the hybrid
system is started.
■
Changing the pre-colli sion warning timing
Press the PCS switch to display the current warning timing on the
multi-information display. Each ti me the PCS switch is pressed with
the warning timing displayed, the warning timing will change as fol-
lows.
If the operation timing setting has been changed, the setting will be
retained the next time the hybrid system is started.
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 th e pre-collision system
1
2
3
Page 228 of 588

2284-5. Using the driving support systems
PRIUS c_U (OM52F96U)
■Operational conditions
The pre-collision system is enabled and determines that the possibility of a
frontal collision with a vehicle is high.
Each function is operational at the following speeds:
●Pre-collision warning:
• Vehicle speed is approximately 10 to 86 mph (15 to 140 km/h).
• The relative speed between your vehicle and a preceding vehicle is
approximately 10 mph (15 km/h) or more.
● Pre-collision brake assist:
• Vehicle speed is approximately 19 to 49 mph (30 to 80 km/h).
• The relative speed between your vehicle and a preceding vehicle is
approximately 19 mph (30 km/h) or more.
● Pre-collision braking:
• Vehicle speed is approximately 7 to 49 mph (10 to 80 km/h).
• The relative speed between your vehicle and a preceding vehicle is
approximately 7 mph (10 km/h) or more.
The system may not operate in the following situations:
● If a battery terminal has been disconnected and reconnected and then the
vehicle has not been driven for a certain amount of time
● If the shift lever is in R
● If VSC is disabled (only the pre-collision warning function will be opera-
tional)
● If the PCS warning light is flashing or illuminated
■ Cancelation of the pre-collision braking
●If either of the following occur while the pre-collision braking function is
operating, it will be canceled:
• The accelerator pedal is depressed strongly.
• The steering wheel is turned sharply or abruptly.
● If the vehicle is stopped by the operation of the pre-collision braking func-
tion, the operation of the pre-collision braking function will be canceled after
the vehicle has been stopped for approximately 2 seconds.
Page 229 of 588
2294-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52F96U)■
Conditions under which the system ma y operate even if there is no pos-
sibility of a collision
● In some situations such as the following, the system may determine that
there is a possibility of a frontal collision and operate.
• If the front of the vehicle is raised or lowered, such as when the road sur-
face is uneven or undulating
• When passing a vehicle in an oncom-
ing lane that is stopped to make a
right/left turn
• When passing an oncoming vehicle while making a left or right 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 rapidly closing on a preceding vehicle
• When passing extremely close to avehicle or structural object
Page 230 of 588
2304-5. Using the driving support systems
PRIUS c_U (OM52F96U)• When driving on a narrow path surrounded by a structure, such as in a
tunnel or on an iron bridge
• When using an automatic car wash • 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
• When rapidly closing on an electric toll gate barrier, parking area barrier,
or other barrier that opens and closes
Page 231 of 588
2314-5. Using the driving support systems
4
Driving
PRIUS c_U (OM52F96U)• When there are patterns or paint on the road or a wall that may be mis-
taken for a vehicle
• 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
• When the sensor is misaligned due to a strong impact being applied to the
sensor, etc.
Page 232 of 588
2324-5. Using the driving support systems
PRIUS c_U (OM52F96U)• 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.