2015 TOYOTA PRIUS Owners Manual

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CAUTION
■Replacing tires
Make sure that all tires are of the specified size and of the same brand, tread
pattern and total load capacity. In addition, make sure that the tires are
inflated to the recommended tire inflation pressure level.
The ABS and VSC systems will not function correctly if different tires are
installed on the vehicle.
Contact your Toyota dealer for further information when replacing tires or
wheels.
■ Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will affect
the driving assist systems, and may cause a system to malfunction.

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Hill-start assist control
■Hill-start assist contro l operating conditions
● The system operates in the following situations:
• The shift position is in a position other than P.
• The parking brake is not applied.
• The accelerator pedal is not depressed.
● Hill-start assist control cannot be operated while the slip indicator light is
illuminated.
■ Hill-start assist control
●While hill-start assist control is operating, the brakes remain automati-
cally applied after the driver releases the brake pedal. The stop lights and
the high mounted stoplight turn on.
● Hill-start assist control operates for about 2 seconds after the brake pedal
is released.
● If the slip indicator does not flash and the buzzer does not sound when
the brake pedal is further depressed, slightly reduce the pressure on the
brake pedal (do not allow the vehicl e to roll backward) and then firmly
depress it again. If the system still does not operate, check if the operat-
ing conditions explained above have been met.
Hill-start assist control helps to prevent the vehicle from rolling
backwards when starting on an incline or slippery slope.
To engage hill-start assist con-
trol, further depress the brake
pedal when the vehicle is
stopped completely.
A buzzer will sound once to
indicate the system is acti-
vated. The slip indicator will
also start flashing.

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■Hill-start assist control buzzer
●When hill-start assist control is activated, the buzzer will sound once.
● In the following situations, hill-start assist control will be canceled and the
buzzer will sound twice.
• No attempt is made to drive the vehicle within approximately 2 seconds
of releasing the brake pedal.
• Push the P position switch.
• The parking brake is applied.
• The brake pedal is depressed again.
• The brake pedal has been depressed for more than approximately 3 minutes.
■ If the slip indicator light comes on
It may indicate a malfunction in the system. Contact your Toyota dealer.
CAUTION
■Hill-start assist control
●Do not overly rely on the hill-start assist control. Hill-start assist control
may not operate effectively on extremely steep inclines or roads covered
in ice.
● Unlike the parking brake, hill-start assist control is not intended to hold the
vehicle stationary for an extended period of time. Do not attempt to use
hill-start assist control to hold the vehicle on an incline for an extended
period of time, as doing so may lead to an accident.

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PCS (Pre-Collision System)
: If equipped
When the radar sensor detects possibility of a frontal collision, the
pre-collision systems such as the brakes and seat belts are automat-
ically engaged to lessen impact as well as vehicle damage.
■ Pre-collision seat belts (front seat belts only)
If the pre-collision sensor detects that a collision is unavoidable, the
pre-collision system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. ( P. 112)
However, when the VSC system is disabled, the system will not oper-
ate in the event of skidding.
■ Pre-collision brake assist
When there is a high possibility of a frontal collision, the system applies
greater braking force in relation to how strongly the brake pedal is
depressed. The system may not warn the driver using a warning light,
warning display and buzzer when the system detects and judges brak-
ing operations.
■Pre-collision braking
When there is a high possibility of a frontal collision, the system warns
the driver using a warning light, warning display and buzzer. If the sys-
tem determines that a collision is unavoidable, the brakes are automat-
ically applied to reduce the collision speed. Pre-collision braking can be
disabled using the pre-collision braking off switch.

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Disabling pre-collision braking
Pre-collision braking enabled
Pre-collision braking disabled
The “PCS” warning light will
turn on when pre-collision
braking is disabled.
Radar sensorThe radar sensor detects vehi-
cles or other obstacles on or
near the road ahead and deter-
mines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles.

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■The pre-collision system is operational when
●Pre-collision seat belts (operating conditions 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 (operating conditions 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.

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■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 may 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.

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■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 your vehicle, such as at an inter-
section
● If a vehicle suddenly cuts in front of your vehicle, such as when overtak-
ing
● 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 th e system, or if the system is tempo-
rarily unusable
Warning lights and/or warning messages will turn on or flash. ( P. 506, 520)