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4-5. Using the driving support systems
WARNING
●Do not use the system in the following situations, as the system may be
unable to correctly assist you in reaching the target parking spot and may
lead to an unexpected accident.
• In an area that is not a parking lot
• A parking lot that is not paved and has no parking space lines, such as
a sand or gravel parking lot
• A parking lot that has a slope or undulations in the road
• A frozen, snow-covered or slippery road
• The asphalt is melting due to hot weather
• There is an obstacle between the vehicle and the target parking spot
• Using tire chains or compact spare tire (if equipped)
● Do not use tire other than that provided by the manufacturer. The system
may not operate properly. When replacing tires, contact your Toyota
dealer.
● The system may not be able position the vehicle in the set location in the
following situations.
• The tires are extremely worn or the tire pressure is low
• The vehicle is carrying very heavy load
• The vehicle is tilted due to having luggage, etc. located on one side of
the vehicle
• There are road heaters installed in the parking lot to prevent the road
surface from freezing.
In any other situations when the set position and vehicle position greatly
differ, have the vehicle inspected by your Toyota dealer.
● Make sure to observe the following precautions regarding the exit parallel
parking assist mode.
Exit parallel parking assist mode is a function used when departing from a
parallel parking spot. However, this function may not be usable if obsta-
cles or people are detected in front of the vehicle. Only use this function
when departing from a parallel parking spot. In the event that the steering
control operates, either turn the system off using the S-APGS switch or
operate the steering wheel to stop the control.
● If exit parallel parking assist mode is mistakenly used in the following situ-
ations, the vehicle may make contact with an obstacle.
The departure function is operated in a direction where an obstacle is
present, but the obstacle is not detected by the side sensors (situations
such as when the vehicle is directly beside a pole).
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4-5. Using the driving support systems
WARNING
■When using the rear view monitor system
The rear view monitor system is a supplemental device intended to assist
the driver when backing up. When backing up, be sure to visually check all
around the vehicle both directly and using the mirrors before proceeding.
Observe the following precautions to avoid an accident that could result in
death or serious injuries.
● Never depend on the rear view monitor system entirely when backing up.
The image and the position of the guide lines displayed on the screen may
differ from the actual state.
Use caution, just as you would when backing up any vehicle.
● Be sure to back up slowly, depressing the brake pedal to control vehicle
speed.
● The instructions given are only guide lines.
When and how much to turn the steering wheel will vary according to traf-
fic conditions, road surface conditions, vehicle condition, etc. when park-
ing. It is necessary to be fully aware of this before using the rear view
monitor system.
● When parking, be sure to check that the parking space will accommodate
your vehicle before maneuvering into it.
● Do not use the rear view monitor system in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or emergency tires
• When the back door is not closed completely
• On roads that are not flat or straight, such as curves or slopes
● In low temperatures, the screen may darken or the image may become
faint. The image could distort when the vehicle is moving, or you may
become unable to see the image on the screen. Be sure to visually check
all around the vehicle both directly and using the mirrors before proceed-
ing.
● If the tire sizes are changed, the position of the fixed guide lines displayed
on the screen may change.
● The camera uses a special lens. The distances between objects and
pedestrians that appear in the image displayed on the screen will differ
from the actual distances. ( →P. 401)
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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.
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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. 674)
■ 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
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PRIUS_OM_OM47B89U_(U)
4114-5. 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. 674
■ 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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4-5. Using the driving support systems
WARNING
■When the TRAC/VSC syst ems 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.
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PRIUS_OM_OM47B89U_(U)
4194-6. Driving tips
4
Driving
Accelerate the vehicle slowly, keep a safe distance between you and
the vehicle ahead, and drive at a reduced speed suitable to road con-
ditions.
Park the vehicle and shift the shift position to P and block the wheel
under the vehicle without setting t he parking brake. The parking brake
may freeze up, preventing it from being released. If the vehicle is
parked without setting the parking brake, make sure to block the
wheels.
Failure to do so may be dangerous because it may cause the vehicle
to move unexpectedly, possibly leading to an accident.
Use the correct tire chain size when mounting the tire chains. Chain
size is regulated for each tire size.
Side chain
0.12 in. (3.0 mm)
1.18 in. (30.0 mm)
0.39 in. (10.0 mm)
Cross chain 0.16 in. (4.0 mm)
0.98 in. (25.0 mm)
0.55 in. (14.0 mm)
Regulations regarding the use of tire chains vary depending on loca-
tion and type of road. Al ways check local regulations before installing
chains.
When driving the vehicle
When parking the vehicle
Selecting tire chains
1
2
3
4
5
6
Regulations on the use of tire chains