2017 TOYOTA PRIUS brakes

PRIUS_OM_OM47B54U_(U)
2094-1. 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 pedal and gentl y depress the accelerator pedal.
Release the parking brake.
■ When starting off on a uphill
The hill-start assist control will activate. ( →P. 403)
■ 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 acceleration. ( →P. 409)
■ 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 rain,
because there may be a layer of water between the tires and the road sur-
face, preventing the steering and brakes from operating properly.
■ Restraining hybrid system outp ut (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. If a warning message is shown on the multi-information
display, read the message and follow the instructions.
■ “ECO Accelerator Guidance” ( →P. 120)
It is easier to drive in an Eco-friendly manner by driving while 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 speed. If exces-
sive acceleration is avoided, the “Eco-Start” score will increase.\
● When driving:
After accelerating to the desired speed, release the accelerator 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 pedal will cause
the “Eco-Stop” score to increase.
Starting off on a steep uphill
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PRIUS_OM_OM47B54U_(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. 235)
● 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, heads or other parts of their body
are not outside the vehicle.
● Do not drive in excess of the speed limit. Even if the legal speed limit per-
mits it, do not drive over 85 mph (140 km/h) unless your vehicle has high-
speed capability tires. Driving over 85 mph (140 km/h) may result 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 slippage 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 side are wet
and not functioning properly, steering control may be affected.

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PRIUS_OM_OM47B54U_(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 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 that 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.

275
PRIUS_OM_OM47B54U_(U)
4-5. Using the driving support systems
4
Driving
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 the possibility of a frontal col-
lision with a vehicle or pedestrian is high, a warning operates to
urge the driver to take evasive action and the potential brake
pressure is increased to help the dr iver avoid the collision. If the
system determines that the possibi lity 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 the
impact of the collision.
The pre-collision system can be disabled/enabled and the warning
timing can be changed. ( →P. 279)

276
PRIUS_OM_OM47B54U_(U)
4-5. Using the driving support systems
◆Pre-collision brake assist
When the system determ ines that the possibility of a frontal colli-
sion is high, the system applies gr eater braking force in relation to
how strongly the brake pedal is depressed.
◆Pre-collision braking
When the system determ ines that the possibility of a frontal colli-
sion is high, the system warns th e driver. 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 the
collision speed.

284
PRIUS_OM_OM47B54U_(U)
4-5. Using the driving support systems
• 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 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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PRIUS_OM_OM47B54U_(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-vehicle dis-
tance button.
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.
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 system then
returns to constant speed cruising.
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PRIUS_OM_OM47B54U_(U)
3414-5. Using the driving support systems
4
Driving
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 will resolve
this problem.)
● The sensor is frozen. (Thawing the area will resolve this problem.)
In especially cold weather, if a sensor is frozen, the screen may 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, motorcycle
engines, air brakes of large vehicles, or other loud noises producing 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 detection range is reduced due to an object such as a sign.
● 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.