Page 238 of 496
2384-5. Using the driving support systems
PRIUS +_OM_OM47888E_(EE)
When your vehicle is too close to a vehicle ahead, and sufficient auto-
matic 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 follow-
ing a vehicle. Apply the brakes to ensure an appropriate vehicle-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
Approach warning
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2404-5. Using the driving support systems
PRIUS +_OM_OM47888E_(EE)■
Automatic cancelation of vehicle -to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the fol-
lowing situations:
● Actual vehicle speed falls below approximately 40 km/h (25 mph).
● VSC is activated.
● The sensor cannot operate correctly because it is covered in some way.
● The windshield wipers are operating at high speed (when the wiper switch is
set to the AUTO mode or the high speed wiper operation position).
If vehicle-to-vehicle distance control driving is automatically canceled for any
other reason, there may be a malfunction in the system. Contact any autho-
rized Toyota dealer or repairer, or another duly qualified and equipped profes-
sional.
■ Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following situ-
ations:
● Actual vehicle speed is more than approximately 16 km/h (10 mph) below
the set vehicle speed.
At this time, the memorized set speed is not retained.
● Actual vehicle speed falls below approximately 40 km/h (25 mph).
● VSC is activated.
■ Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-
vehicle distance control operates properly. (Some obstructions, such as
snow, ice and plastic objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control (vehicle-to-vehicle distance control mode) is
canceled if an obstruction is detected. (Constant speed control mode can be
used.)
■ Warning lights, warning messages and buzzers for dynamic radar cruise
control
Warning lights, warning messages and buzzers are used to indicate a system
malfunction or to inform the driver of the need for caution while driving.
(→ P. 391)
Grille cover
Radar sensor
1
2
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2434-5. Using the driving support systems
4
Driving
PRIUS +_OM_OM47888E_(EE)
WARNING
■ 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 det ermines 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 ens ure the safety of all involved.
■ To avoid inadvertent cr uise control activation
Switch the cruise control off using the “ON-OFF” button when not in use.
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2444-5. Using the driving support systems
PRIUS +_OM_OM47888E_(EE)
WARNING
■ Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate speed control and could cause an acci-
dent resulting in death or serious injury.
●Except on highways or expressways
● In heavy traffic
● On roads with sharp bends
● On winding roads
● On slippery roads, such as those covered with rain, ice or snow
● On steep downhills, or where ther e are sudden changes between sharp up
and down gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
● At entrances to expressways
● When weather conditions are bad enough that they may prevent the sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
● When an approach warning buzzer is heard often
■ When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes (or accelerator pedal) as necessary when any of the fol-
lowing 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. 238) 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 in the same lane
● Vehicles with small rear ends (trailers with no load on board etc.)
● Motorcycles traveling in the same lane
● When water or snow thrown up by the surrounding vehicles hinders the
detecting of the sensor
Page 245 of 496
2454-5. Using the driving support systems
4
Driving
PRIUS +_OM_OM47888E_(EE)
WARNING
■ Conditions under which the vehicle-to-vehicle distance control may
not function correctly
Apply the brakes (or accelerator pedal) as necessary in the following condi-
tions as the radar sensor may not be able to correctly detect vehicles
ahead, and a fatal or serious accident may result:
●When the vehicle ahead of you decelerates suddenly
When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)
●When the road curves or when the
lanes are narrow
● When steering wheel operation or your
position in the lane is unstable
Accelerate
Accelerate
Decelerate
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2464-5. Using the driving support systems
PRIUS +_OM_OM47888E_(EE)
WARNING
■ Handling the radar sensor
Observe the following to ensure the cruise control system can function
effectively.
Otherwise, the system may not function correctly and could result in an
accident.
●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 moves even slightly off position, the system may become
inaccurate or malfunction. If the sensor or surrounding area is subject to a
strong impact, always have the area inspected and adjusted by any autho-
rized Toyota dealer or repairer, or another duly qualified and equipped pro-
fessional.
● 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.
● Do not replace them with non-genuine parts.
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2504-5. Using the driving support systems
PRIUS +_OM_OM47888E_(EE)
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRC and
hill-start assist control systems
Any of the following conditions may occur when the above systems are oper-
ating. None of these indicates that a malfunction has occurred.
●Vibrations may be felt through the vehicle body and steering.
● A motor sound may be heard after the vehicle comes to a stop.
● The brake pedal may pulsate slightly after the ABS is activated.
● The brake pedal may move down slightly after the ABS is activated.
■ ECB operating sound
ECB operating sound may be heard in the following cases, but it does not
indicate that a malfunction has occurred.
●Operating sound heard from the engine compartment when the brake pedal
is operated.
● Motor sound of the brake system heard from the front part of the vehicle
when the driver’s door is opened.
● Operating sound heard from the engine compartment when 1-2 minutes
passed after the stop of the hybrid system.
■ EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■ Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from
overheating when there is frequent steering input over an extended period of
time. The steering wheel may feel heavy as a result. Should this occur, refrain
from excessive steering input or stop the vehicle and turn the hybrid system
off. The EPS system should return to normal within 10 minutes.
■ Electric power steering system warning light (warning buzzer)
→ P. 377
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2524-5. Using the driving support systems
PRIUS +_OM_OM47888E_(EE)
WARNING
■ The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (such as
excessively worn tires on a snow covered road).
● The vehicle hydroplanes while driving at high speed on wet or slick road.
■ Stopping distance when the ABS is operating may exceed that of nor-
mal conditions
The ABS is not designed to shorten t he vehicle’s stopping distance. Always
maintain a safe distance from the vehicle in front of you, especially in the
following situations:
● When driving on dirt, gravel or snow-covered roads
● When driving with tire chains
● When driving over bumps in the road
● When driving over roads with potholes or uneven surfaces
■ TRC may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRC system is operating.
Drive the vehicle carefully in conditions where stability and power may be
lost.
■ Hill-start assist control does not operate effectively when
●Do not overly rely on the hill-start assist control. The hill-start assist control
may not operate effectively on steep inclines and roads covered with 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, as doing so may
lead to an accident.
■ When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may
cause an accident. Exercise particular care when the indicator light flashes.