TOYOTA PRIUS 2021 Owners Manual (in English)

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4214-5. Using the driving support systems
4
Driving
◆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
◆E-Four (Electronic On-Demand AWD system) (AWD models)
Automatically switches from fron t-wheel drive to all-wheel drive
(AWD) according to the driving conditions, helping to ensure re li-
able handling and stability. Ex amples of conditions where the s ys-
tem will switch to AWD are when cornering, going uphill, starting off
or accelerating, and when the road surface is slippery due to s now,
rain, etc.
The slip indicator light will flash
while the TRAC/VSC/ABS sys-
tems are operating.
When the TRAC/VSC/ABS systems are operating

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4-5. Using the driving support systems
If the vehicle gets stuck in mud, dirt or snow, the TRAC 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 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 sys-
tem 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 will come on and the “Traction Control Tu rned 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 ass ist 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. 593)
■ When the message is displayed on the multi-information display show-
ing that TRAC has been disab led even if has not been pressed
TRAC is temporary deactivated. If the information continues to show, contact
your Toyota dealer.
■ Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assi st control will
operate:
● The shift position is in a position other than P or N (when sta rting off forward/
backward on an upward incline)
● The vehicle is stopped
● The accelerator pedal is not depressed
● The parking brake is not engaged
Disabling the TRAC system

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4234-5. Using the driving support systems
4
Driving
■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 re leased.
■ Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC 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 mal function has
occurred in any of these systems.
● Any of the following conditions may occur when the above system s are
operating. None of these indicates that a malfunction has occur red.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a s top.
■ 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 brak e pedal
is operated.
● Motor sound of the brake system heard from the front part of th e vehicle
when the driver’s door is opened.
● Operating sound heard from the engine compartment when one or t wo 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 so und) may be
heard. This does not indicate a malfunction.
■ 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 wh en vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-e nabling
will not occur when vehicle speed increases.

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4-5. Using the driving support systems
■Operating conditions of Active Cornering Assist
The system operates when the following occurs.
●TRAC/VSC can operate
● The driver is attempting to accelerate while turning
● The system detects that the vehicle is drifting to the outer si de
● The brake pedal is released
■ Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the s ystem from
overheating when there is frequent steering input over an exten ded period of
time. The steering wheel may feel heavy as a result. Should thi s 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 wa rning light (warning buzzer)
P. 593
■ When a message related to AWD system is displayed on the multi-infor-
mation display (AWD models)
Perform the following actions.
MessageDetailsActions
“AWD System Overheated
Switching to 2WD Mode”AWD system is over-
heating.Stop the vehicle for a
certain amount of time
or drive the vehicle at
approximately 6 mph
(10 km/h) 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 Overheated 2WD Mode Engaged”
The vehicle switched
from all-wheel drive
(AWD) to front wheel
drive due to over-
heating.
“AWD System Malfunction
2WD Mode EngagedVisit Your Dealer”
A malfunction
occurred in the AWD
system, and the
vehicle switched to
front wheel drive.
Have the vehicle
inspected by your Toy-
ota dealer immediately.

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4254-5. Using the driving support systems
4
Driving
WARNING
■The ABS does not operate effectively when
● The limits of tire gripping performance have been exceeded (suc h as
excessively worn tires on a snow covered road).
● The vehicle hydroplanes while driving at high speed on wet or s lick 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, espe cially 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 system is operating. D rive the
vehicle carefully in conditions where stability and power may b e lost.
■ Active Cornering Assist does not operate effectively when
● Do not overly rely on Active Cornering Assist. Active Cornering Assist may
not operate effectively when accelerating down slopes or driving on slip-
pery road surfaces.
● When Active Cornering Assist frequently operates, Active Corner ing
Assist may temporarily stop operating to ensure proper operatio n of the
brakes, TRAC and VSC.
■ Hill-start assist control does not operate effectively when
● Do not overly rely on hill-start assist control. Hill-start ass ist control may
not operate effectively on steep inclines and roads covered wit h ice.
● Unlike the parking brake, hill-start assist control is not inte nded 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/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.

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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 r oad condi-
tions. As these are the systems to help ensure vehicle stabilit y 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, brand, trea d pattern and
total load capacity. In addition, make sure that the tires are inflated to the
recommended tire inflation pressure level.
The ABS, TRAC and VSC systems will not function correctly if di fferent tires
are installed on the vehicle.
Contact your Toyota dealer for further information when replaci ng tires or
wheels.
■ Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspensio n will affect
the driving assist systems, and may cause a system to malfuncti on.

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4-6. Driving tips
4
Driving
Hybrid vehicle driving tips
◆Using Eco drive mode
When using Eco drive mode, the torque corresponding to the accel-
erator pedal depression amount can be generated more smoothly
than it is in normal conditions. In addition, the operation of the air
conditioning system (heating/coo ling) will be minimized, improving
the fuel economy. ( P. 347)
◆Use of Hybrid System Indicator
The Eco-friendly driving is possible by keeping the Hybrid Syst em
Indicator within Eco area. ( P. 129)
◆Shift position operation
Shift the shift position to D when stopped at a traffic light, or driving
in heavy traffic etc. Shift the shift position to P when parkin g. When
using the N, there is no positiv e effect on fuel consumption. In the
N, the gasoline engine operates but electricity cannot be gener -
ated. Also, when using the air conditioning system, etc., the h ybrid
battery (traction batt ery) power is consumed.
◆Accelerator pedal/brake pedal operation
●Drive your vehicle smoothly. Avoid abrupt acceleration and
deceleration. Gradual accelerat ion and deceleration will make
more effective use of the electric motor (traction motor) witho ut
having to use gaso line engine power.
● Avoid repeated acceleration. Repeated acceleration consumes
hybrid battery (tracti on battery) power, resulting in poor fuel con-
sumption. Battery power can be restored by driving with the
accelerator pedal slightly released.
For economical and ecological dri ving, pay attention to the fol-
lowing points:

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4-6. Driving tips
◆When braking
Make sure to operate the brakes gently and in a timely manner. A
greater amount of electrical energy can be regenerated when slow-
ing down.
◆Delays
Repeated acceleration and deceleration, as well as long waits a t
traffic lights, will lead to bad fuel economy. Check traffic re ports
before leaving and avoid delays as much as possible. When drivi ng
in a traffic jam, gently release the brake pedal to allow the v ehicle to
move forward slightly while avoiding overuse of the accelerator
pedal. Doing so can help control excessive gasoline consumption.
◆Highway driving
Control and maintain the vehicle at a constant speed. Before st op-
ping at a toll booth or similar, allow plenty of time to releas e the
accelerator and gently apply the brakes. A greater amount of el ec-
trical energy can be regenerated when slowing down.
◆Air conditioning
Use the air conditioning only when necessary. Doing so can help
reduce excessive gasoline consumption.
In summer: When the ambient tempe rature is high, use the recircu-
lated air mode. Doing so will help to reduce the burden on the air
conditioning system and reduce fuel consumption as well.
In winter: Because the gasolin e engine will not automatically cut out
until it and the interior of the vehicle are warm, it will cons ume fuel.
Also, fuel consumption can be improved by avoiding overuse of t he
heater.

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4294-6. Driving tips
4
Driving
◆Checking tire inflation pressure
Make sure to check the tire inflation pressure frequently. Improper
tire inflation pressure can cause poor fuel economy.
Also, as snow tires can cause large amounts of friction, their use on
dry roads can lead to poor fuel economy. Use tires that are app ro-
priate for the season.
◆Luggage
Carrying heavy luggage will lead to poor fuel economy. Avoid carry-
ing unnecessary luggage. Installing a large roof rack will also cause
poor fuel economy.
◆Warming up before driving
Since the gasoline engine starts up and cuts out automatically
when cold, warming up the engine is unnecessary. Moreover, fre-
quently driving short distances will cause the engine to repeat edly
warm up, which can lead to excess fuel consumption.

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4-6. Driving tips
Winter driving tips
●Use fluids that are appropriate t o the prevailing outside tempera-
tures. • Engine oil
• Engine/power control unit coolant
• Washer fluid
● Have a service technician inspect the condition of the 12-volt bat-
tery.
● Have the vehicle fitted with four snow tires or purchase a set of tire
chains for the front tires.
Ensure that all tires are the same size and brand, and that cha ins match
the size of the tires.
Perform the following accordi ng to the driving conditions:
● Do not try to forcibly open a window or move a wiper that is fr ozen.
Pour warm water over the frozen area to melt the ice. Wipe away
the water immediately to p revent it from freezing.
● To ensure proper operation of the climate control system fan,
remove any snow that has accumulated on the air inlet vents in
front of the windshield.
● Check for and remove any excess ic e or snow that may have accu-
mulated on the exterior lights, vehicle’s roof, chassis, around the
tires or on the brakes.
● Remove any snow or mud from the bottom of your shoes before
getting in the vehicle.
Carry out the necessary preparations and inspections before
driving the vehicle in winter. Always drive the vehicle in a ma n-
ner appropriate to the prevailing weather conditions.
Preparation for winter
Before driving the vehicle