2017 TOYOTA PRIUS Owners Manual

PRIUS_OM_OM47B54U_(U)
4014-5. Using the driving support systems
4
Driving
NOTICE
■How to use the camera
● The rear view monitor system may not operate properly in the following
cases.
• If the back of the vehicle is hit, the position and mounting angle of the
camera may change.
• As the camera has a water proof construction, do not detach, disassem- ble or modify it. This may cause incorrect operation.
• When cleaning the camera lens, flush the camera with a large quantity of water and wipe it with a soft and wet cloth. Strongly rubbing the cam-
era lens may cause the camera lens to be scratched and unable to
transmit a clear image.
• Do not allow organic solvent, car wax, window cleaner or a glass coat- ing to adhere to the camera. If this happens, wipe it off as soon as pos-
sible.
• If the temperature changes rapidly, such as when hot water is poured on the vehicle in cold weather, the system may not operate normally.
• When washing the vehicle, do not apply intensive bursts of water to the camera or camera area. Doing so may result in the camera malfunc-
tioning.
● Do not expose the camera to strong impact as this could cause a malfunc-
tion. If this happens, have the vehicle inspected by your Toyota dealer as
soon as possible.

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4-5. Using the driving support systems
Driving assist systems
◆ECB (Electronically Controlled Brake System)
The electronically controlled system generates braking force corre-
sponding to the brake operation
◆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
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning 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
To help enhance driving safety and performance, the following
systems operate automatically in response to various driving
situations. Be aware, however, that these systems are supple-
mentary and should not be relied upon too heavily when operat-
ing the vehicle.

PRIUS_OM_OM47B54U_(U)
4034-5. Using the driving support systems
4
Driving
◆Enhanced VSC (Enhanced Ve hicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery
road surfaces by controllin g steering performance.
◆Hill-start assist control
Helps to reduce the vehicle from rolling backward when starting on
a uphill
The slip indicator light will flash
while the VSC/TRAC/ABS sys-
tems are operating.
When the VSC/TRAC/ABS systems are operating

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4-5. Using the driving support systems
If the vehicle gets stuck in mud, di rt or snow, the TRAC system may
reduce power from the hybrid sy stem to the wheels. Pressing
to turn the system off may make it easier for you to rock the vehicle in
order to free it.
To turn the TRAC system off,
quickly press and release
.
The “Traction Control Turned Off”
will be shown on the multi-informa-
tion display. Press
again to
turn the system back on.
■ Turning off both TRAC and VSC systems
To turn the TRAC and VSC systems off, press and hold for more than
3 seconds while the vehicle is stopped.
The VSC OFF indicator light will come on and the “Traction Control Turned
Off” will be shown on the multi-information display.
*
Press again to turn the systems back on.
*: On vehicles with pre-collision system, pre-collision brake assist and pre-
collision braking will also be disabled. The PCS warning light will come on
and the message will be shown on the multi-information display. ( →P. 654)
■ When the message is displayed on th e multi-information display show-
ing that TRAC has been disable d even if has not been pressed
TRAC cannot be operated. Contact your Toyota dealer.
Disabling the TRAC system

PRIUS_OM_OM47B54U_(U)
4054-5. Using the driving support systems
4
Driving
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC 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 also 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 or 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.

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4-5. Using the driving support systems
■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.
■ Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automati-
cally re-enabled in the following situations:
● When the power switch is turned off
● If only the TRAC system is turned off, the TRAC will turn on when vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-enabling will
not occur when vehicle speed increases.
■ Electric power steering system warning light (warning buzzer)
→P. 654
■ Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will
operate:
● The shift position is in a position other than P or N (when starting off forward/
backward on an upward incline)
● The vehicle is stopped
● The accelerator pedal is not depressed
● The parking brake is not engaged
■ Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
● Shift the shift position to P or N
● The accelerator pedal is depressed
● The parking brake is engaged
● Approximately 2 seconds elapse after the brake pedal is released

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4074-5. Using the driving support systems
4
Driving
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 the 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
■ TRAC/VSC may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRAC/VSC systems are 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 TRAC, VSC an d/or ABS is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may
cause an accident. Exercise particular care when the indicator light flashes.

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4-5. Using the driving support systems
WARNING
■When the TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road condi-
tions. As these are systems to help ensure vehicle stability and driving
force, do not turn the TRAC/VSC systems off unless necessary.
■ Replacing tires
Make sure that all tires are of the specified size and of the same brand,
tread pattern and total load capacity. In addition, make sure that the tires are
inflated to the recommended tire inflation pressure level.
The ABS, VSC and TRAC and other driving assist systems will not function
correctly if different tires are installed on the vehicle.
Contact your Toyota dealer for further information when replacing tires or
wheels.
■ Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will affect
the driving assist systems, and may cause a system to malfunction.