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PRIUS +_OM_OM47841E_(EE)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
When the vehicle ahead is driving slower than the set speed
When a vehicle is detected running ahead of you, the system automati-
cally decelerates your vehicle. When a greater reduction in vehicle speed
is necessary, the system applies the brakes. A warning tone warns you
when the system cannot decelerate sufficiently to prevent your vehicle
from closing in on the vehicle ahead.
Example of follow-up cruising
When following a vehicle driving slower than the set speed
The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration
When there are no longer any vehicles ahead driving slower than
the set speed
The system accelerates until the set speed is reached. The system then
returns to constant speed cruising.
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279 2-4. Using other driving systems
2
When driving
PRIUS +_OM_OM47841E_(EE)
Approach warning
When your vehicle is too close to a vehicle ahead, and sufficient
automatic deceleration via the cruise control is not possible, the dis-
play will flash and the buzzer will sound to alert the driver. An exam-
ple of this would be if another driver cuts in front of you while you are
following a vehicle. Apply the brakes to ensure an appropriate vehi-
cle-to-vehicle distance.
Warnings may not occur when
In the following instances, there is a possibility that the warnings
will not occur:
When the speed of the vehicle ahead matches or exceeds your
vehicle speed
When the vehicle ahead is traveling at an extremely slow speed
Immediately after the cruise control speed was set
At the instant the accelerator is applied
Selecting conventional constant speed control mode
Constant speed control mode differs from vehicle-to-vehicle distance
control mode. When constant speed mode is selected, your vehicle
will maintain a set speed regardless of whether or not there are other
vehicles in the lane ahead.
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When driving
PRIUS +_OM_OM47841E_(EE)
CAUTION
Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your
vehicle and vehicles ahead by applying the brakes etc.
Cautions regarding the driving assist systems
Observe the following precautions.
Failure to do so may cause an accident resulting in death or serious injury.
Assisting the driver to measure following distance
The dynamic radar cruise control is only intended to help the driver in
determining the following distance between the driver’s own vehicle and a
designated vehicle traveling ahead. It is not a mechanism that allows care-
less or inattentive driving, and it is not a system that can assist the driver in
low-visibility conditions. It is still necessary for driver to pay close attention
to the vehicle’s surroundings.
Assisting the driver to judge proper following distance
The dynamic radar cruise control determines whether the following dis-
tance between the driver’s own vehicle and a designated vehicle traveling
ahead is appropriate or not. It is not capable of making any other type of
judgement. Therefore, it is absolutely necessary for the driver to remain
vigilant and to determine whether or not there is a possibility of danger in
any given situation.
Assisting the driver to operate the vehicle
The dynamic radar cruise control has no capability to prevent or avoid a
collision with a vehicle traveling ahead. Therefore, if there is ever any dan-
ger, the driver must take immediate and direct control of the vehicle and
act appropriately in order to ensure the safety of all involved.
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When driving
PRIUS +_OM_OM47841E_(EE)
CAUTION
When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles
are in front of you.
As the sensor may not be able to correctly detect these types of vehicles,
the approach warning (P. 279) will not be activated, and a fatal or serious
accident may result.
Vehicles that cut in suddenly
Vehicles traveling at low speeds
Vehicles that are not moving
Vehicles with small rear ends (trailers with no load on board etc.)
Motorcycles traveling in the same lane
Conditions under which the vehicle-to-vehicle distance control may
not function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor may not be able to correctly detect vehicles ahead, and a fatal or serious
accident may result:
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.)
When the road curves or when the lanes are narrow
When steering wheel operation or your position in the lane is unstable
When the vehicle ahead of you decelerates suddenly
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2-4. Using other driving systems
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When driving
PRIUS +_OM_OM47841E_(EE)
Driving assist systems
To help enhance driving safety and performance, the following sys-
tems operate automatically in response to various driving situations.
Be aware, however, that these systems are supplementary and
should not be relied upon too heavily when operating the vehicle.
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
TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spin-
ning 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
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292 2-4. Using other driving systems
PRIUS +_OM_OM47841E_(EE)
VSC+ (Vehicle Stability Control+)
Provides cooperative control of the ABS, TRC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controlling steering performance.
Hill-start assist control
P. 297
PCS (Pre-Crash Safety System) (if equipped)
P. 300
Emergency brake signal (if equipped)
When the brakes are applied suddenly, the stop lights automati-
cally flash to alert the vehicle behind.
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298 2-4. Using other driving systems
PRIUS +_OM_OM47841E_(EE)
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 vehicle 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.
• 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 any authorized Toyota
dealer or repairer, or another duly qualified and equipped professional.
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PCS (Pre-Crash Safety System)
: If equipped
When the radar sensor detects possibility of a frontal collision, the
pre-crash safety systems such as the brakes and seat belts are auto-
matically engaged to lessen impact to occupants as well as vehicle
damage.
Pre-crash seat belts (front seat belts only)
If the pre-crash sensor detects that a collision is unavoidable, the pre-
crash safety 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. 1 1 9 )
However, when the VSC system is disabled, the system will not oper-
ate in the event of skidding.
Pre-crash 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-crash 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-crash braking can be
disabled using the pre-crash braking off switch.