brakes TOYOTA PRIUS 2021 Owners Manual (in English)

PRIUS_OM_OM47E09U_(U)
2294-1. Before driving
4
Driving
Firmly set the parking brake with the brake pedal depressed, and
then shift the shift position to D.
Release the brake ped al and gently depress the accelerator peda l.
Release the parking brake.
■ When starting off on an uphill
The hill-start assist control will activate. ( P. 421)
■ For fuel-efficient driving
Keep in mind that hybrid vehicles are similar to conventional vehicles, and it
is necessary to refrain from activities such as sudden accelera tion. (P. 427)
■ Driving in the rain
●Drive carefully when it is raining, because visibility will be reduced, the win-
dows may become fogged-up, and the road will be slippery.
● Drive carefully when it starts to rain, because the road surface will be espe-
cially slippery.
● Refrain from high speeds when driving on an expressway in the r ain,
because there may be a layer of water between the tires and the road sur-
face, preventing the steering and brakes from operating properl y.
■ Restraining the hybrid system o utput (Brake Override System)
● When the accelerator and brake pedals are depressed at the same time, the
hybrid system output may be restrained.
● A warning message is displayed on the multi-information display while the
system is operating. ( P. 608)
■ “ECO Accelerator Guidance” (P. 130)
It is easier to drive in an Eco-friendly manner by driving whil e referring to the
“ECO Accelerator Guidance” display. Also, by using the “ECO Accelerator
Guidance”, it is easier to increase the Eco score evaluation.
● When starting off:
While staying within the “ECO Accelerator Guidance” range, gradually
depress the accelerator pedal and accelerate to the desired spe ed. If exces-
sive acceleration is avoided, the “Eco-Start” score will increa se.
● When driving:
After accelerating to the desired speed, release the accelerato r pedal and
drive at a stable speed within the “ECO Accelerator Guidance” range. By
keeping the vehicle within the “ECO Accelerator Guidance” range, the “Eco-
Cruise” score will increase.
● When stopping:
When stopping the vehicle, early releasing the accelerator peda l will cause
the “Eco-Stop” score to increase.
Starting off on a steep uphill
1
2
3

232
PRIUS_OM_OM47E09U_(U)
4-1. Before driving
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When driving the vehicle
● Use engine braking (shift position B instead of shift position D) to maintain
a safe speed when driving down a steep hill.
Using the brakes continuously may cause the brakes to overheat and lose
effectiveness. ( P. 256)
● Do not adjust the positions of the steering wheel, the seat, or the inside or
outside rear view mirrors while driving.
Doing so may result in a loss of vehicle control.
● Always check that all passengers’ arms, head or other parts of their body
are not outside the vehicle.
● AWD models: Do not drive the vehicle off-road.
This is not an AWD vehicle designed for off-road driving. Proce ed with all
due caution if it becomes unavoidable to drive off-road.
● Do not drive across river crossings or through other bodies of water.
This may cause electric/electronic components to short circuit, damage
the hybrid system or cause other serious damage to the vehicle.
● Do not drive in excess of the speed limit. Even if the legal sp eed limit per-
mits it, do not drive over 85 mph (140 km/h) unless your vehicl e has high-
speed capability tires. Driving over 85 mph (140 km/h) may resu lt in tire
failure, loss of control and possible injury. Be sure to consult a tire dealer
to determine whether the tires on your vehicle are high-speed c apability
tires or not before driving at such speeds.
■ When driving on slippery road surfaces
● Sudden braking, acceleration and steering may cause tire slippa ge and
reduce your ability to control the vehicle.
● Sudden acceleration, engine braking due to shifting, or changes in engine
speed could cause the vehicle to skid, resulting in an accident .
● After driving through a puddle, depress the brake pedal to make sure that
the brakes are functioning properly. Wet brake pads may prevent the
brakes from functioning properly. If the brakes on only one sid e are wet
and not functioning properly, steering control may be affected.

236
PRIUS_OM_OM47E09U_(U)
4-1. Before driving
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When taking a nap in the vehicle
Always turn the hybrid system off. Otherwise, if you accidentally move the
shift lever or depress the accelerator pedal, this could cause an accident or
fire due to hybrid system overheating. Additionally, if the vehicle is parked in
a poorly ventilated area, exhaust gases may collect and enter the vehicle,
leading to death or a serious health hazard.
■ When braking
● When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and this ma y cause
one side of the vehicle to brake differently than the other sid e. Also, the
parking brake may not securely hold the vehicle.
● If the electronically controlled assist function does not opera te, do not fol-
low other vehicles closely and avoid downhill or sharp turns th at require
braking.
In this case, braking is still possible, but the brake pedal sh ould be
depressed more firmly than usual. Also, the braking distance wi ll increase.
Have your brakes fixed immediately.
● The brake system consists of 2 or more individual hydraulic systems; if
one of the systems fails, the other(s) will still operate. In t his case, the
brake pedal should be depressed more firmly than usual and the braking
distance will increase. Have your brakes fixed immediately.
■ If the vehicle becomes stuck (AWD models)
Do not spin the wheels excessively when any of the tires is up in the air, or
the vehicle is stuck in sand, mud, etc. This may damage the driveline com-
ponents or propel the vehicle forward or backward, causing an a ccident.

296
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
PCS (Pre-Collision System)
The system can detect the following:
●Vehicles
● Bicyclists
● Pedestrians
: If equipped
The pre-collision system uses a radar sensor and front camera
to detect objects ( P. 296) in front of the vehicle. When the sys-
tem determines that the possibility of a frontal collision with an
object is high, a warning operates to urge the driver to take e va-
sive action and the potential brake pressure is increased to he lp
the driver avoid the collision. If the system determines that t he
possibility of a frontal collision with an object is extremely high,
the brakes are automatically applied to help avoid the collisio n
or help reduce the impa ct of the collision.
The pre-collision system can b e disabled/enabled and the warnin g
timing can be changed. ( P. 3 0 0 )
Detectable objects

PRIUS_OM_OM47E09U_(U)
2974-5. Using the driving support systems
4
Driving
■Pre-collision warning
When the system determines
that the possibility of a frontal
collision is high, a buzzer will
sound and a warning message
will be displayed on the multi-
information display to urge the
driver to take evasive action.
■Pre-collision brake assist
When the system determines that the possibility of a frontal colli-
sion is high, the system applies greater braking force in relat ion to
how strongly the brake pedal is depressed.
■Pre-collision braking
If the system determines that the possibility of a frontal collision is
extremely high, the brakes are automatically applied to help avoid
the collision or reduce th e impact of the collision.
System functions

306
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
• If the wheels are misaligned
• If a wiper blade is blocking the front camera
• The vehicle is being driven at extremely high speeds
• When driving on a hill
• If the radar sensor or front camera is misaligned
● In some situations such as the following, sufficient braking fo rce 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 sli ppery sur-
face
■ If VSC is disabled
●If VSC is disabled ( P. 422), 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-Coll ision Brake
System Unavailable” will be displayed on the multi-information display.
• If the front of the vehicle is raised or
lowered

PRIUS_OM_OM47E09U_(U)
3314-5. 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.
Example of deceleration crui sing 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 s peed 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 su ffi-
ciently to prevent your vehicle fr om closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehicle will also stop (vehicle is
stopped by system control). After the vehicle ahead starts off, pushing the
cruise control lever up or depressing the accelerator pedal (st art-off opera-
tion) will resume follow-up cruising. If the start-off operatio n is not per-
formed, system control continues to keep your vehicle stopped.
When the turn signal lever is operated and your vehicle moves to an over-
taking lane while driving at 50 mph (80 km/h) or more, the vehi cle will
accelerate to help to overtake a passing vehicle.
The system’s identification of what is an overtaking lane may b e deter-
mined solely based on the location of the steering wheel in the vehicle (left
side driver position versus right side driver position.) If the vehicle is driven
to a region where the overtaking lane is on a different side fr om where the
vehicle is normally driven, the vehicle may accelerate when the turn signal
lever is operated in the opposite direction to the overtaking l ane (e.g., if the
driver normally operates the vehicle in a region where the overtaking lane
is to the right but then drives to a region where the overtaking lane is to the
left, the vehicle may accelerate when the right turn signal is activated).
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 syst em then
returns to constant speed cruising.
1
2
3

370
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
WARNING
■Sensors
Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where
this may occur are listed below.
● There is dirt, snow or ice on the sensor. (Wiping the sensors w ill resolve
this problem.)
● The sensor is frozen. (Thawing the area will resolve this probl em.)
In especially cold weather, if a sensor is frozen, the screen m ay show an
abnormal display, or obstacles may not be detected.
● The sensor is covered in any way.
● In harsh sunlight or intense cold weather
● On an extremely bumpy road, on an incline, on gravel, or on grass
● The vicinity of the vehicle is noisy due to vehicle horns, moto rcycle
engines, air brakes of large vehicles, or other loud noises pro ducing ultra-
sonic waves.
● The sensor is splashed with water or drenched with heavy rain.
● The sensor is drenched with water on a flooded road.
● The vehicle is leaning considerably to one side.
● The vehicle is equipped with a fender pole or wireless antenna.
● The vehicle is approaching a tall or curved curb.
● The area directly under the bumpers is not detected.
● If obstacles draw too close to the sensor.
● The bumper or sensor receives a strong impact.
● A non-genuine Toyota suspension (lowered suspension etc.) is in stalled.
● There is another vehicle equipped with parking assist sensors i n the vicin-
ity.
● Towing eyelets are installed.
● A backlit license plate is installed.
In addition to the examples above, depending on the shape and c ondition of
obstacles, detection may not be possible, or the detection rang e may be
shortened.

376
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
When the Parking Support Brake f unction detects an obstacle with a
probability of collision, hybrid system output is restricted to restrain an
increase in vehicle speed. (Hybri d system output restriction control: A)
Furthermore, when the accelerator pedal continues to be depress ed,
the brakes are applied to reduce the vehicle speed. (Brake control: B)
Operation
DOWN
DOWN
UP
ON
OFF
ON
OFF
ON
OFF

386
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
S-APGS (Simple Adva nced Parking Guidance
System)

■Function summary
The Simple Advanced Parking Guidance System automatically
operates the steering wheel to provide support when backing int o
an area near a target parking spot, and when departing from a p ar-
allel parking spot. (Changing the shift position and speed adju st-
ment when moving forward or backing up are not performed
automatically.)
● The Simple Advanced Parking Guidance System does not park
the vehicle automatically. It is a system that provides support
when pulling out of a perpendicular or parallel parking spot.
● The Simple Advanced Parking Guidance System provides steer-
ing wheel operation assistance to guide the vehicle toward the
selected intended parking spot. The selected intended parking
spot may not always be reach able, depending on road and vehi-
cle conditions at the time of parking, and the distance to the
intended parking spot.
■Linking with the Parking Support Brake function
While the Simple Advanced Parking Guidance System is operating,
if the system detects an obstacl e that could result in a collision, the
emergency brakes operate, regardl ess of whether the Parking Sup-
port Brake function is on or off. ( P. 388)
: If equipped
Simple Advanced Parking Guidance System
WARNING
●When backing up or proceeding forward, be sure to directly conf irm the
safety of the area to the front or rear, and the area around the vehicle, and
slowly back up or proceed forward while adjusting the vehicle s peed by
depressing the brake pedal.
● If it seems the vehicle may make contact with a pedestrian, ano ther vehi-
cle or any other obstacles, stop the vehicle by depressing the brake pedal,
and then press the S-APGS switch ( P. 389) to turn the system off.