brakes TOYOTA PRIUS 2020 Owners Manual (in English)

PRIUS_OM_OM47D44U_(U)
2254-1. 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. 409)
■ 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. 415)
■ 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. 596)
■ “ECO Accelerator Guidance” (P. 128)
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
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PRIUS_OM_OM47D44U_(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. 252)
● 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. Proceed 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 capability
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.

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PRIUS_OM_OM47D44U_(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 veh icle 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 may cause
one side of the vehicle to brake differently than the other side. Also, the
parking brake may not securely hold the vehicle.
● If the electronically controlled assist function does not operate, 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 should be
depressed more firmly than usual. Also, the braking distance will 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 this 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 accident.

292
PRIUS_OM_OM47D44U_(U)
4-5. Using the driving support systems
PCS (Pre-Collision System)
◆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.
: If equipped
The pre-collision system uses a radar sensor and camera sen-
sor to detect vehicles and pedest rians in front of your vehicle.
When the system determines that t he possibility of a frontal col-
lision with a vehicle or pedest rian is high, a warning operates to
urge the driver to take evasive action and the potential brake
pressure is increased to help the driver avoid the collision. If the
system determines that the possi bility of a frontal collision with
a vehicle or pedestrian is extremely high, the brakes are auto-
matically applied to help avoid the collision or help reduce th e
impact of the collision.
The pre-collision system can b e disabled/enabled and the warnin g
timing can be changed. ( P. 2 9 6 )

PRIUS_OM_OM47D44U_(U)
2934-5. Using the driving support systems
4
Driving
◆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
When the system determines that the possibility of a frontal colli-
sion is high, the system warns the driver. If the system determ ines
that the possibility of a frontal collision is extremely high, the brakes
are automatically applied to hel p avoid the collision or reduce the
collision speed.

PRIUS_OM_OM47D44U_(U)
3014-5. Using the driving support systems
4
Driving
• When driving in inclement weather such as heavy rain, fog, snow or a
sandstorm
• 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 d riven for a
certain amount of time
• While making a left/right turn and for a few seconds after mak ing a left/
right turn
• While driving on a curve and for a few seconds after driving o n 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 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 the front of the vehicle is raised or
lowered

320
PRIUS_OM_OM47D44U_(U)
4-5. Using the driving support systems
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-ve hicle dis-
tance switch.
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 will resume fol-
low-up cruising.
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.
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3

328
PRIUS_OM_OM47D44U_(U)
4-5. Using the driving support systems
■Automatic cancelation of c onstant 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.
● Parking Support Brake function is operated. (if equipped)
If constant speed control mode is automatically canceled for an y other rea-
son, there may be a malfunction in the system. Contact your Toyota dealer.
■ Brake system operation sound
If the brakes are applied automatically while the vehicle is in vehicle-to-vehi-
cle distance control mode, a brake system operation sound may b e heard.
This does not indicate a malfunction.
■ Warning messages and buzzers for d ynamic radar cruise control with
full-speed range
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 correctly detect ing the vehicle ahead
In the case of the following and depending on the conditions, o perate 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 o f vehicles, the
approach warning ( P. 325) 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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PRIUS_OM_OM47D44U_(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 installed.
● There is another vehicle equipped with parking assist sensors in the vicin-
ity.
● Towing eyelets are installed.
● A backlit license plate is installed.
In addition to the examples above, depending on the shape and condition of
obstacles, detection may not be possible, or the detection range may be
shortened.

364
PRIUS_OM_OM47D44U_(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