Page 511 of 818

5095-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
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
◆Hill-start assist control
Helps to reduce the backward movement of the vehicle when start-
ing on an uphill
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.
Page 512 of 818
5105-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
◆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.
The slip indicator light will flash
while the TRC/VSC/ABS systems
are operating.
When the TRC/VSC/ABS systems are operating
Page 514 of 818

5125-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(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.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
Page 516 of 818

5145-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
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 roads.
■ 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
■ TRC/VSC may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRC/VSC system is 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 hill-start assist control. 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 TRC/ABS/VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may
cause an accident. Exercise particular care when the indicator light flashes.
Page 517 of 818

5155-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
WARNING
■When the TRC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road condi-
tions. As these are the systems to help ensure vehicle stability and driving
force, do not turn the TRC/VSC systems off unless necessary.
■ Replacing tires
Make sure that all tires are of the specified size, 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, TRC and VSC systems will not function correctly if different tires
are installed on the vehicle.
Contact any authorized Toyota retailer or Toyota authorized repairer, or any
reliable repairer 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.
Page 575 of 818

5737-1. Maintenance and care
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
7
Maintenance and care
Clean the air intake vents and fil-
ters by the following procedures to
prevent dust from accumulating in
them, or to prevent them from
clogging.
The filters are attached to the back
side of the air intake vent grilles.
■
Cleaning the air intake vents and filters
Remove the dust from the vents
and filters with a vacuum
cleaner etc.
Clean the vents of the both
sides.
■
Cleaning the filters
If “Maintenance Required for Traction Battery Cooling Parts See
Owner’s Manual” is shown on the multi-information display, remove
the air intake vent grilles on the both sides of the rear seat and
clean the filters.
Insert a flathead screwdriver
etc. to the notch at the edge
of the grille to disconnect the
3 tabs, and remove the grille.
Turn over the rubber portion
beside the grille to insert the flat-
head screwdriver.
To prevent damage, cover the
tip of the flathead screwdriver
with a rag.
Cleaning the air intake vents and filters
1
Page 576 of 818
5747-1. Maintenance and care
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
Remove the filter.
Remove dust using a vac-
uum cleaner etc. to clean the
filter.
Also, remove dust on the grille
as well as on the filter using a
vacuum cleaner.
Reinstall the filter to the origi-
nal position.
Be careful not to deform the fil-
ter or allow a gap between the
filter and the installation posi-
tion when installing the filter.
Insert the tabs at the edge of
the grille to the positions, and
push the opposite side edge
in to secure the grille.
Reinstall the grille to the original
position while turning over the
rubber portion.
Start the hybrid system and check that the warning message on
the multi-information display disappears.
It may take several minutes before the warning message disappears.
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3
4
5
6
Page 618 of 818
6167-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
Pull the cover to disconnect the
tabs, and remove the cover.
Turn the portion to loosen
the jack, and slowly take out the
jack.
Be careful when handling the jack,
as it may become hot depending
on conditions. (P. 614)
If the portion can not be loos-
ened, turn it using the jack handle.
Taking out the jack
1
2A
A