2014 TOYOTA SIENNA Owners Manual

337
2-4. Using other driving systems
2
When driving
SIENNA_OM_OM45483U_(U)
Hill-start assist control
: If equipped
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 that the system is acti-
vated. The slip indicator will
also start flashing.

338 2-4. Using other driving systems
SIENNA_OM_OM45483U_(U)
■Hill-start assist control can be operated when
• The shift lever is in a position other than P.
• The parking brake is not applied.
• The accelerator pedal is not depressed.
■ 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 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.
• The shift lever is moved to P.
• 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 comes on...
It may indicate a malfunction in the system. Contact your Toyota dealer.

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When driving
SIENNA_OM_OM45483U_(U)
CAUTION
■Hill-start assist control
●Do not overly rely on 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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SIENNA_OM_OM45483U_(U)
PCS (Pre-Collision System)
: If equipped
When the radar sensor detects possibility of a frontal collision, the
pre-collision system such as t he brakes and seat belts are auto-
matically engaged to lessen impact as well as vehicle damage.
■ Pre-collision seat belts (front seat belts only)
If the pre-collision s ensor detects that a co llision is unavoidable,
the pre-collision system will retract the seat belt before the colli-
sion occurs. The same will happen if the driver makes an emer-
gency braking or loses co ntrol of the vehicle. (P. 132)
However, when the VSC system is disabled, the system will not
operate 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.
■ Pre-collision braking
When there is a high possibility of a frontal collision, the system
warns the driver using a warning light and buzzer. If the system
determines that a collision is un avoidable, the brakes are auto-
matically applied to reduce th e collision speed. Pre-collision
braking can be disabled usi ng the pre-collision braking off
switch.

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When driving
SIENNA_OM_OM45483U_(U)
Disabling pre-collision braking
Pre-collision braking disabled
Pre-collision braking enabled
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.

342 2-4. Using other driving systems
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■The pre-collision system is operational when
●Pre-collision seat belts (type A):
• 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 seat belts (type B):
• 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 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:
• The pre-collision braking off switch is not pressed.
• 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).

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When driving
SIENNA_OM_OM45483U_(U)
■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
● 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 climbing a steep hill or going down a downhill slope causes an
overhead billboard or other metallic structure to appear directly in the
vehicle’s line of travel
● When there are excessive changes in the vehicle height (when it tilts for-
wards or backwards)
● When passing through an electronic toll collection gate (only in countries
with electronic toll collection)
● When the axis of the radar is out of adjustment
● When passing through the 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.
■ Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may
also be occasions when the radar sensor cannot detect pedestrians, ani-
mals, bicycles, motorcycles, trees, or snowdrifts.

344 2-4. Using other driving systems
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■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 such as 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 warning messages will turn on or flash. ( P. 743)