2012 TOYOTA PRIUS Owners Manual

305
2-4. Using other
driving systems
2
When driving
■The pre-collision system is operational when
●Pre-collision seat belts (type A)
• Vehicle speed is greater than about 19 mph (30 km/h).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
● Pre-collision seat belts (type B)
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the
vehicle running ahead of you is greater than about 19 mph (30 km/h).
• The front occupants are wearing a seat belt.
● Pre-collision brake assist:
• Vehicle speed is greater than about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the
vehicle running ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
● Pre-collision braking:
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the
vehicle running ahead of you is greater than about 10 mph (15 km/h).
• The pre-collision braking off switch is not pressed.

306 2-4. Using other driving systems
■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
● 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.

307
2-4. Using other
driving systems
2
When driving
■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.
■ Situations in which the pre-collis ion 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 vehicle, such as at an intersection
● If a vehicle suddenly cuts in front of vehicle, such as when overtaking
● 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-collision system
When a malfunction occurs due to sensor contamination, etc. that results in
the sensors being unable to detect obstacles, the pre-collision 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
Warning lights and/or warning messages will turn on or flash. ( P. 496, 509)

308 2-4. Using other driving systems
■Certification
For vehicles sold in the U.S.A.
FCC ID: HYQDNMWR004
This device complies with part 15 of the FCC Rules. Operation is subject to
the following two conditions: (1) This device may not cause harmful interfer-
ence, and (2) this device must accept any interference received, including
interference that may cause undesired operation.
FCC WARNING
Changes or modifications not expressly approved by the party responsible
for compliance could void the user’s authority to operate the equipment.
Radiofrequency radiation exposure Information:
This equipment complies with FCC radiation exposure limits set forth for an
uncontrolled environment.
This equipment should be installed and operated with minimum distance of
20 cm between the radiator (antenna) and your body.
This transmitter must not be co-located or operating in conjunction with any
other antenna or transmitter.
For vehicles sold in Canada
Operation is subject to the following two conditions: (1) this device may not
cause interference, and (2) this device must accept any interference, includ-
ing interference that may cause undesired operation of the device.

309
2-4. Using other
driving systems
2
When driving
CAUTION
■Limitations of the pre-collision system
Do not overly rely on the pre-collision system. Always drive safely, taking
care to observe your surroundings and checking for any obstacles or other
road hazards.
Failure to do so may cause an accident resulting in death or serious injury.
■ Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-collision system is intended
to assist the driver in avoiding collisions through the process of LOOK-
JUDGE-ACT. There are limits to the degree of assistance the system can
provide, so please keep in mind the following important points.
●Assisting the driver in watching the road
The pre-collision system is only able to detect obstacles directly in front of
the vehicle, and only within a limited range. It is not a mechanism that
allows careless or inattentive driving, and it is not a system that can assist
the driver in low-visibility conditions. It is still necessary for the driver to
pay close attention to the vehicle’s surroundings.
● Assisting the driver in making correct judgement
When attempting to estimate the possibility of a collision, the only data
available to the pre-collision system is that from obstacles it has detected
directly in front of the vehicle. Therefore, it is absolutely necessary \
for the
driver to remain vigilant and to determine whether or not there is a possi-
bility of collision in any given situation.
● Assisting the driver in taking action
The pre-collision system’s braking assist feature is designed to help
reduce the severity of a collision, and so only acts when the system has
judged that a collision is unavoidable. This system by itself is not capable
of automatically avoiding a collision or bringing the vehicle to a stop safely.
For this reason, when encountering a dangerous situation the driver must
take direct and immediate action in order to ensure the safety of all
involved.

310 2-4. Using other driving systems
CAUTION
■When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary in any of the following situations.
●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.)
● Vehicles that cut in suddenly
● Vehicles with small rear ends (trailers with no load on board etc.)
● Motorcycles traveling in the same lane
■ Handling the radar sensor
Observe the following to ensure the pre-collision system can function effec-
tively:
●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 has moved out of position, the system may malfunction or
operate incorrectly. If the sensor or surrounding area is subject to a strong
impact, always have the area inspected and adjusted by your Toyota
dealer.
● 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.

311
2
When driving
2-5. Driving information
Cargo and luggage
Take notice of the following information about storage precau-
tions, cargo capacity and load:
●Stow cargo and luggage in the luggage compartment whenever
possible.
● Be sure all items are secured in place.
● To maintain vehicle balance while driving, position luggage
evenly within the luggage compartment.
● For better fuel economy, do no t carry unnecessary weight.

312 2-5. Driving information
Capacity and distributionCargo capacity depends on the total weight of the occupants.
(Cargo capacity) = (Total load capa city) — (Total weight of occupants)
Steps for Determining Correct Load Limit 
(1) Locate the statement “The combined weight of occupants and cargo should never exceed XXX kg or XXX lbs.” on your vehicle’s
placard.
(2) Determine the combined weight of the driver and passengers that
will be riding in your vehicle.
(3) Subtract the combined weight of the driver and passengers from XXX kg or XXX lbs.
(4) The resulting figure equals the av ailable amount of cargo and lug-
gage load capacity.
For example, if the “XXX” amount equals 1400 lbs. and there will
be five 150 lb passengers in your vehicle, the amount of available
cargo and luggage load capacity is 650 lbs. (1400  750 (5150)
= 650 lbs.)
(5) Determine the combined weight of luggage and cargo being loaded on the vehicle. That wei ght may not safely exceed the
available cargo and luggage load capacity calculated in Step 4.
(6) If your vehicle will be towing a trai ler, load from your trailer will be
transferred to your vehicle. Consult this manual to determine how
this reduces the available cargo and luggage load capacity of
your vehicle. ( P. 316)
Toyota does not recommend towing a trailer with your vehicle. Your
vehicle is not designed for trailer towing.