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• When driving in inclement weather such as heavy rain, fog, snow or asandstorm
• 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 driven for a certain amount of time
• While making a left/right turn and for a few seconds after making a left/ right turn
• While driving on a curve and for a few seconds after driving on 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 force 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 slippery sur-
face
• If the front of the vehicle is raised or
lowered
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■If the PCS warning light flashes or illuminates and a warning message is
displayed on the multi-information display
The pre-collision system may be temporarily unavailable or there may be a
malfunction in the system.
●In the following situations, the warning light will turn off, the message will
disappear and the system will become operational when normal operating
conditions return:
• When the radar sensor or camera s ensor or the area around either sen-
sor is hot, such as in the sun
• When the radar sensor or camera s ensor or the area around either sen-
sor is cold, such as in an extremely cold environment
• When a front sensor is dirty or covered with snow, etc.
• When the part of the windshield in front of the camera sensor is fogged up or covered with condensation or ice (Defogging the windshield:
P. 362)
• If the camera sensor is obstructed, such as when the hood is open or a sticker is attached to the windshield near the camera sensor
● If the PCS warning light continues to flash or remains illuminated or the
warning message does not disappear even though the vehicle has returned
to normal, the system may be malfunctioning. Have the vehicle inspected by
your Toyota dealer immediately.
■ If VSC is disabled
●If VSC is disabled ( P. 254), the pre-collision brake assist and pre-collision
braking functions are also disabled.
● The PCS warning light will turn on and “VSC TURNED OFF PRE-
COLLISION BRAKE SYSTEM UNAVAILABLE” will be displayed on the
multi-information display.
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2314-5. Using the driving support systems
4
Driving
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-
vehicle distance can also be set by operating the vehicle-to-vehicle dis-
tance control.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed
appears
When a vehicle is detected running ahead of you, the system automatically
decelerates your vehicle. When a greater reduction in vehicle speed is
necessary, the system applies the brakes (the stop lights will come on at
this time). The system will respond to changes in the speed of the vehicle
ahead in order to maintain the vehicle-to-vehicle distance set by the driver.
Approach warning warns you when the system cannot decelerate suffi-
ciently to prevent your vehicle from closing in on the vehicle ahead.
Example of acceleration
When there are no longer any preceding vehicles driving slower
than the set speed
The system accelerates until the set speed is reached. The system then
returns to constant speed cruising.
1
2
3
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PRIUS v_OM_OM47B78U_(U)
2354-5. Using the driving support systems
4
Driving
Pulling the lever toward you
cancels the speed control.
The speed control is also canceled
when the brake pedal is
depressed.
Pushing the lever up resumes
the cruise control and returns
vehicle speed to the set speed.
However, cruise control does not resume when the vehicle speed is
approximately 25 mph (40 km/h) or less.
When your vehicle is too close to
a vehicle ahead, and sufficient
automatic deceleration via the
cruise control is not possible, the
display will flash and the buzzer
will sound to alert the driver. An
example of this would be if
another driver cuts in front of you
while you are following a vehicle.
Depress the brake pedal to
ensure an appropriate vehicle-to-
vehicle distance.
■Warnings may not occur when
In the following instances, warnings may not occur even when the
vehicle-to-vehicle distance is small.
●When the speed of the preceding vehicle matches or exceeds
your vehicle speed
● When the preceding vehicle is traveling at an extremely slow
speed
● Immediately after the cruise control speed was set
● When depressing the accelerator pedal
Canceling and resuming the speed control
1
2
Approach warning (vehicle-to-vehicle distance control mode)
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4-5. Using the driving support systems
■Automatic cancelation of constant speed control mode
Constant speed control mode is automatically canceled in the following situa-
tions:
●Actual vehicle speed is more than approximately 10 mph (16 km/h) below
the set vehicle speed.
● Actual vehicle speed falls below approximately 25 mph (40 km/h).
● VSC is activated.
● TRAC is activated for a period of time.
● When the VSC or TRAC system is turned off.
● Pre-collision braking is activated.
If constant speed control mode is automatically canceled for any other rea-
son, there may be a malfunction in the system. Contact your Toyota dealer.
■ Warning messages and buzzers for dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. If a warning message
is shown on the multi-information display, read the message and follow the
instructions.
■ When the sensor may not be corr ectly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the
brake pedal when deceleration of the system is insufficient or operate the
accelerator pedal when acceleration is required.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning ( P. 235) may not be activated.
● Vehicles that cut in suddenly
● Vehicles traveling at low speeds
● Vehicles that are not moving in the same lane
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4-5. Using the driving support systems
■Conditions under which the vehicle-to-vehicle distance control mode
may not function correctly
In the case of the following conditions, operate the brake pedal (or accelera-
tor pedal, depending on the situation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system
may not operate properly.
●When the vehicle ahead of you decelerates suddenly
●
When the road curves or when the lanes
are narrow
● When steering wheel operation or your
position in the lane is unstable
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4
Driving
WARNING
■When using the rear view monitor system
The rear view monitor system is a supplemental device intended to assist
the driver when backing up. When backing up, be sure to visually check all
around the vehicle both directly and using the mirrors before proceeding.
Observe the following precautions to avoid an accident that could result in
death or serious injuries.
●Never depend on the rear view monitor system entirely when backing up.
The image and the position of the guide lines displayed on the screen may
differ from the actual state.
Use caution, just as you would when backing up any vehicle.
● Be sure to back up slowly, depressing the brake pedal to control vehicle
speed.
● The instructions given are only guide lines.
When and how much to turn the steering wheel will vary according to traf-
fic conditions, road surface conditions, vehicle condition, etc. when park-
ing. It is necessary to be fully aware of this before using the rear view
monitor system.
● When parking, be sure to check that the parking space will accommodate
your vehicle before maneuvering into it.
● Do not use the rear view monitor system in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or emergency tires
• When the back door is not closed completely
• On roads that are not flat or straight, such as curves or slopes
● In low temperatures, the screen may darken or the image may become
faint. The image could distort when the vehicle is moving, or you may
become unable to see the image on the screen. Be sure to visually check
all around the vehicle both directly and using the mirrors before proceed-
ing.
● If the tire sizes are changed, the position of the fixed guide lines displayed
on the screen may change.
● The camera uses a special lens. The distances between objects and
pedestrians that appear in the image displayed on the screen will differ
from the actual distances. ( P. 244)
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Driving assist systems
◆ECB (Electronically Controlled Brake System)
The electronically controlled system generates braking force corre-
sponding to the brake operation
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly,
or if the brakes are applied while driving on a slippery road surface
◆Brake assist
Generates an increased level of braking force after the brake pedal
is depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or
turning on slippery road surfaces
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning when starting the vehicle or accelerating on slippery roads
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to
turn the steering wheel
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery
road surfaces by controlling steering performance.
To help enhance driving safety and performance, the following
systems operate automatically in response to various driving
situations. Be aware, however, that these systems are supple-
mentary and should not be relied upon too heavily when operat-
ing the vehicle.