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4394-5. Using the driving support systems
4
Driving
PRIUS_OM_OM47F32E_(EE)
WARNING
●Observe the following precautions, as the sensors may stop functioning
properly which may lead to an accident.
• Do not subject the sensor to strong shocks by hitting it, etc. The sen-
sors may not function properly.
• When using a high-pressure washer to wash the vehicle, do not spray
water directly on the sensors. Equipment may not function properly if
subjected to an impact from strong water pressure. If the vehicle
bumper strikes something, equipment may not operate properly due to
a sensor malfunction. Have the vehicle inspected at any authorized
Toyota retailer or Toyota authoriz ed repairer, or any reliable repairer.
● In the following situations, the sensors may not operate normally and may
lead to an accident. Drive carefully.
• Obstacles cannot be detected in the side areas until a scan of the side
areas is completed. ( P. 388)
• Even after the scan of the side areas is completed, obstacles such as
other vehicles, people or animals that approach from the sides cannot
be detected.
• The sensor is frozen (if it thaws, the system returns to normal).
A warning message may display at particularly low temperatures due to
the sensor freezing and it may not detect parked vehicles.
• The sensor is blocked by someone’s hand.
• The vehicle is tilted a large amount.
• The temperature is extremely hot or cold.
• The vehicle is driven on undulating roads, slopes, gravel roads, in areas
with tall grass, etc.
• An ultrasonic wave source is nearby, such as the horn or sensors of
another vehicle, a motorcycle engine or the air brake of a large vehicle.
• Heavy rain or a water strikes the vehicle.
• The angle of the sensor may be deviated when assist control starts
even if there is a parked vehicle in the target parking spot. Have the
vehicle inspected at any authorized Toyota retailer or Toyota authorized
repairer, or any reliable repairer.
• Do not install any accessories within the sensor detection range.
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4404-5. Using the driving support systems
PRIUS_OM_OM47F32E_(EE)
GPF (Gasoline Par ticulate Filter) system
■If “Exhaust Filter Full See Owner’s Manual” is shown on the multi-infor-
mation display
● The message may be displayed while high load driving with particulate mat-
ter accumulating.
● Hybrid system output (engine speed) is restricted when a certain amount of
particulate matter accumulates, however, it is possible to drive the vehicle
unless the malfunction indicator lamp comes on.
● Particulate matter can accumulate more quickly if the vehicle is frequently
driven short trips or at low speeds, or if the hybrid system is regularly started
in an extremely cold environment. Excessive accumulation of particulate
matter can be prevented by periodically driving long distances continuously
with intermittent releasing of the accelerator pedal, such as when driving on
highways and freeways.
■ If the malfunction indicator lamp comes on or “Exhaust Filter Full Visit
Your Dealer” is shown on the multi-information display
The amount of accumulated particulate matter has exceeded a certain level.
Have the vehicle inspected by any authorized Toyota retailer or Toyota autho-
rized repairer, or any reliable repairer immediately.
: If equipped
The GPF system collects particulate matter in the exhaust gas
by using an exhaust gas filter.
The system will operate to regenerate the filter automatically,
depending on the vehicle conditions.
NOTICE
■ To prevent the GPF system from not operating properly
● Do not use fuel other than the specified type
● Do not modify the exhaust pipes
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441
4
4-5. Using the driving support systems
Driving
PRIUS_OM_OM47F32E_(EE)
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.
◆VSC+ (Vehicle Stability Control+)
Provides cooperative control of the ABS, TRC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery
road surfaces by controlling steering performance.
◆TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning when starting the vehicle or accelerating on slippery roads
◆Active Cornering Assist (ACA)
Helps to prevent the vehicle from drifting to the outer side by per-
forming inner wheel brake control when attempting to accelerate
while turning
To keep driving safety and performance, the following systems
operate automatically in response to various driving situations.
Be aware, however, that these systems are supplementary and
should not be relied upon too heavily when operating the vehi-
cle.
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4424-5. Using the driving support systems
PRIUS_OM_OM47F32E_(EE)
◆Hill-start assist control
Helps to reduce the backward movement of the vehicle when start-
ing on an uphill
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to
turn the steering wheel
◆Emergency brake signal
When the brakes are applied suddenly, the emergency flashers
automatically flash to alert the vehicle behind.
◆E-Four (Electronic On-Demand AWD system) (AWD models)
Automatically switches from front-wheel drive to all-wheel drive
(AWD) according to the driving conditions, helping to ensure reli-
able handling and stability. Examples of conditions where the sys-
tem will switch to AWD are when cornering, going uphill, starting off
or accelerating, and when the road surface is slippery due to snow,
rain, etc.
The slip indicator light will flash
while the TRC/VSC/ABS systems
are operating.
When the TRC/VSC/ABS systems are operating
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4434-5. Using the driving support systems
4
Driving
PRIUS_OM_OM47F32E_(EE)
If the vehicle gets stuck in mud, dirt or snow, the TRC system may
reduce power from the hybrid system 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 TRC 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 sys-
tem back on.
■ Turning off both TRC and VSC systems
To turn the TRC and VSC systems off, press and hold for more than 3
seconds while the vehicle is stopped.
The VSC OFF indicator 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. 582)
■ When the message is displayed on the multi-information display show-
ing that TRC has been disable d even if has not been pressed
TRC is temporary deactivated. If the information continues to show, contact
any authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
Disabling the TRC system
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4444-5. Using the driving support systems
PRIUS_OM_OM47F32E_(EE)■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
●No more than 2 seconds have elapsed after the brake pedal is released.
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRC and
hill-start assist control systems
●A sound may be heard from the engine compartment when the brake pedal
is depressed repeatedly, when the hybrid system is started or just after the
vehicle begins to move. This sound does not indicate that a malfunction has
occurred in any of these systems.
●Any of the following conditions may occur when the above systems are
operating. 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.
■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 one or two min-
utes passed after the stop of the hybrid system.
■Active Cornering Assist operation sounds and vibrations
When the Active Cornering Assist is operated, operation sounds and vibra-
tions may be generated from the brake system, but this is not a malfunction.
■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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4454-5. Using the driving support systems
4
Driving
PRIUS_OM_OM47F32E_(EE)■Automatic reactivation of TRC and VSC systems
After turning the TRC and VSC systems off, the systems will be automatically
re-enabled in the following situations:
●When the power switch is turned off
●If only the TRC system is turned off, the TRC will turn on when vehicle
speed increases
If both the TRC and VSC systems are turned off, automatic re-enabling will
not occur when vehicle speed increases.
■Operating conditions of Active Cornering Assist
The system operates when the following occurs.
●TRC/VSC can operate
●The driver is attempting to accelerate while turning
●The system detects that the vehicle is drifting to the outer side
●The brake pedal is released
■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.
■Electric power steering system warning light (warning buzzer)
P. 581
■Operating conditions of emergency brake signal
When the following conditions are met, the emergency brake signal will oper-
ate:
●The emergency flashers are off.
●Actual vehicle speed is over 55 km/h (35 mph).
●The system judges from the vehicle deceleration that it is a sudden braking
operation.
■Automatic system cancelation of emergency brake signal
The emergency brake signal will be canceled in any of the following situa-
tions:
●The emergency flashers are turned on.
●The system judges from the vehicle deceleration that is not a sudden brak-
ing operation.
Page 448 of 770
4464-5. Using the driving support systems
PRIUS_OM_OM47F32E_(EE)■When a message related to AWD system is displayed on the multi-infor-
mation display (AWD models)
Perform the following actions.
MessageDetailsActions
“AWD System Over-
heated
Switching to 2WD
Mode”
AWD system is over-
heating.
Stop the vehicle for a
certain amount of time
or drive the vehicle at
approximately 10 km/h
(6 mph) or more to
reduce the overload to
the system. Once the
display message on the
multi-information dis-
play turns off, there is
no problem continuing
to drive.
“AWD System Over-
heated
2WD Mode Engaged”
The vehicle switched
from all-wheel drive
(AWD) to front wheel
drive due to overheat-
ing.
“AWD System Malfunc-
tion
2WD Mode Engaged
Visit Your Dealer”A malfunction occurred
in the AWD system,
and the vehicle
switched to front wheel
drive.
Have the vehicle
inspected by any
authorized Toyota
retailer or Toyota autho-
rized repairer, or any
reliable repairer imme-
diately.