2023 TOYOTA PRIUS PRIME Owners Manual

732-1. Plug-in hybrid system
2
Plug-in hybrid system
The plug-in hybrid system oper-
ates in the following modes.
The meter display can be used to
check which mode the plug-in
hybrid system is currently being
driven in. (P.150)
■EV mode
When a sufficient amount of
electricity is remaining after
charging
*1, EV driving is per-
formed using electricity stored in
the hybrid battery (traction bat-
tery).
*2
When in EV mode, the EV drive
mode indicator illuminates.
*1: The amount of remaining charge can be checked on the SOC
(State of Charge) gauge.
( P.155)
*2: Depending on the situation, EV
driving may be canceled and
both gasoline engine and electric
motor are used. ( P.79)
■AUTO EV/HV mode
Normally, the electricity stored
in the hybrid battery (traction
battery) is used for EV driving.
However, when more power is
required, such as for driving
uphill or accelerating suddenly,
the gasoline engine starts and
provides powerful acceleration
by strongly depressing the
accelerator pedal.
When the vehicle is in a condi-
tion where EV driving is possi-
ble, EV mode and AUTO EV/HV
mode can be switched by oper-
ating the switch. ( P.74)
When in AUTO EV/HV mode, the
AUTO EV/HV mode indicator illumi-
nates.
■HV mode
When in HV mode, the vehicle is
driven using both the gasoline
Plug-in hybrid system
operation mode

742-1. Plug-in hybrid system
engine and electric motor.
(P.77)
• If electricity needed for EV driving in EV mode or AUTO
EV/HV mode is not remaining,
the operation mode will be
automatically switched to HV
mode.
• The operation mode can be switched to HV mode at any
timing by operating the switch
to keep electricity for EV driv-
ing etc. ( P.74).
* Switching
to HV mode when driving on a
highway or when driving uphill
is recommended in order to
conserve battery power.
When in HV mode, the HV drive
mode indicator illuminates.
*: The EV driving range may reduce even after switching to HV mode.
■Hybrid battery (traction bat-
tery) charge mode ( P.75)
Electricity generated by the gas-
oline engine can be used to
charge the hybrid battery (trac-
tion battery) by switching to the
hybrid battery (traction battery)
charge mode when electricity
needed for EV driving is not remaining.
*
• The system may not be able
to switch to the hybrid battery
(traction battery) charge
mode due to the state of the
plug-in hybrid system.
( P.76)
• Charging time differs depend- ing on the driving state of the
vehicle when driving in hybrid
battery (traction battery)
charge mode.
When in the hybrid battery (traction
battery) charge mode, the hybrid
battery charge mode indicator illu-
minates.
*: When in the hybrid battery (trac-tion battery) charge mode, the
hybrid battery can be charged
while driving. However, the gaso-
line engine runs to charge the
battery and fuel consumption
becomes higher compared with
driving in HV mode.
The plug-in hybrid system oper-
ation modes can be switched
using the switches.
■Switching the plug-in
hybrid system operation
modes
Press the AUTO EV/HV mode
switch or EV/HV mode selection
switch to change modes as the
following table shows.
When in EV mode, the EV drive
Plug-in hybrid system
operation mode selection
switches

752-1. Plug-in hybrid system
2
Plug-in hybrid system
mode indicator illuminates.
When in AUTO EV/HV mode, the
AUTO EV/HV mode indicator illumi-
nates.
When in HV mode, the HV drive
mode indicator illuminates.
AUTO EV/HV mode switch
*: If there is not enough charge remaining in the hybrid battery
(traction battery) to allow EV driv-
ing, AUTO EV/HV mode will not
be selectable.
EV/HV mode selection switch
*: If there is not enough charge remaining in the hybrid battery
(traction battery) to allow EV driv-
ing, EV mode will not be select-
able.
■Switching to the hybrid bat-
tery (traction battery)
charge mode
Press and hold the EV/HV mode
selection switch.
Take your hand off the switch once
the hybrid battery charge mode
indicator starts to blink.
The hybrid battery charge mode
indicator illuminates when the
switch to hybrid battery (traction
battery) charge mode is complete.
When the hybrid battery (traction
battery) is sufficient charged
*, the
hybrid battery (traction battery)
charge mode is automatically can-
celed and the operation mode will
be switched to HV mode.
The hybrid battery (traction bat-
tery) charge mode will be canceled
by pressing AUTO EV/HV mode
switch or EV/HV mode selection
switch.
*: The maximum charge amount in the hybrid battery (traction bat-
tery) charge mode is approxi-
mately 80% of the sufficient
charged capacity for the charging
Current modeMode after switching
EV modeAUTO EV/HV mode
AUTO EV/HV modeEV mode
HV modeAUTO EV/HV
mode
*
Current modeMode after switching
EV modeHV mode
AUTO EV/HV modeHV mode
HV modeEV mode*

762-1. Plug-in hybrid system
from an external power source.
■If the plug-in hybrid system
operation mode cannot be
changed
In the following situations, the plug-
in hybrid system operation mode
cannot be changed even if the
AUTO EV/HV mode switch or
EV/HV mode selection switch is
pressed. (In this case, the warning
message is displayed on the multi-
information displa y when the switch
is pressed.)
●When electricity needed for EV
driving is not remaining (when in
EV mode or AUTO EV/HV mode)
●When the hybrid battery (traction
battery) is almost completely
charged (hybrid battery [traction
battery] charge mode)
■When switching from EV mode
to another mode using the
switch
When the power switch is turned off,
operation mode switching is can-
celed and the system returns to EV
mode the next time the vehicle is
started.
*
*
: If there is not enough charge remaining in the hybrid battery
(traction battery) to allow EV driv-
ing, the system switches to HV
mode.
■Hybrid battery (traction battery)
charge mode
●The following may occur to protect the system, etc.
• Cannot switch to hybrid battery (traction battery) charge mode or
cannot cancel it
• Gasoline engine does not start or stops even after switching to
hybrid battery (traction battery)
charge mode
●If a load to the system is large,
such as when the power con-
sumption of the air conditioning
system is large or when the tem-
perature of the engine coolant is
high, it may take longer time than
usual to charge using the hybrid
battery (traction battery) charge
mode, or charging to the hybrid
battery (traction battery) may not
be performed.
■When in EV mode
In EV mode, EV driving (driving
WARNING
■When using the hybrid bat-
tery (traction battery) charge
mode
Observe the following precautions
when using the hybrid battery
(traction battery) charge mode
while parking.
Failure to do so may lead to death
or serious health hazard, as the
gasoline engine operates when in
the hybrid battery (traction bat-
tery) charge mode.
●Do not stop the vehicle near
flammable materials.
●Do not use the hybrid battery
(traction battery) charge mode
in a closed area where ventila-
tion is insufficient, such as in a
garage or area with snow
buildup.
Control when driving in
each mode

772-1. Plug-in hybrid system
2
Plug-in hybrid system
using only the electric motor)* is
possible. However, depending
on the situation, EV driving may
be canceled and both gasoline
engine and electric motor are
used ( P.79). Also, if a little
electricity is remaining in the
hybrid battery (traction battery),
HV mode is automatically
selected. To drive in EV mode
long, observe the followings.
 Avoid sudden acceleration
and sudden deceleration, and
be sure to drive smoothly. If
you repeatedly accelerate,
the hybrid battery (traction
battery) charge will deplete
quickly. Also, EV driving may
be canceled by rapid acceler-
ation or vehicle speed.
 Restrain your speed as much
as possible. The distance that
can be driven in EV mode will
reduce considerably at high
speeds.
*: The EV driving range can be
checked using the meter.
( P.155)
■When in AUTO EV/HV mode
Only the electric motor is used
for EV driving
* during normal
driving, but when the accelera-
tor pedal is strongly depressed,
the gasoline engine starts.
( P.79)
Also, when the hybrid battery
(traction battery) level is low, the
mode switches to HV mode automatically the same as in EV
mode.
AUTO EV/HV mode is suitable
for driving conditions when more
power is required, such as for
driving uphill or accelerating
suddenly. However, because
the gasoline engine will start
more easily, it is recommended
to drive in EV mode usually.
*: The EV driving range can be
checked using the meter.
( P.155)
■When in HV mode
The vehicle can be used in the
same way as a standard Plug-in
Hybrid Electric Vehicle
In HV mode, controls are pri-
marily carried out as follows in
accordance with the driving con-
ditions.
 The gasoline engine stops
*
when the vehicle is stopped.
 During start off, the electric
motor (traction motor) drives
the vehicle.
 During normal driving, the
gasoline engine and electric
motor (traction motor) are
controlled effectively, and the
vehicle is driven with optimum
fuel efficiency. Also, when
necessary, the electric motor
(traction motor) operates as
an electrical generator to
charge the hybrid battery
(traction battery).

782-1. Plug-in hybrid system
When the accelerator pedal is
depressed heavily, drive force
from both the gasoline engine
and the electric motor (trac-
tion motor) is used to acceler-
ate.
*: When the hybrid battery (traction
battery) requires charging or the
engine is warming up, etc., the
gasoline engine will not automati-
cally stop. ( P.79)
■When braking (regenera-
tive braking)
The electric motor (traction
motor) charges the hybrid bat-
tery (traction battery).
The EV driving range can be
extended by actively using this
regenerative braking to store
electricity in the hybrid battery
(traction battery).
Moreover, as fuel consumption
is also reduced when in HV
mode, the regenerative braking
system can be used effectively.
■Regenerative braking
●In the following situations, kinetic
energy is converted to electric
energy and deceleration force can
be obtained in conjunction with
the recharging of the hybrid bat-
tery (traction battery).
• The accelerator pedal is released while driving with the shift position
in D or B.
• The brake pedal is depressed while driving with the shift position
in D or B.
●The Regeneration Boost oper-
ates when the shift position is
shifted to B. The regenerative
braking force can be changed when the Regeneration Boost is
operating. (
P.260)
■EV driving range
●The EV driving range is displayed
on the meter. ( P.155)
●The EV driving range changes in
accordance with the charge status
of the hybrid battery (traction bat-
tery), the speed of the vehicle, etc.
●Even if there is enough charge
remaining in the hybrid battery
(traction battery), EV driving may
be canceled and both gasoline
engine and electric motor are
used depending on the situation.
( P.79)
■EV indicator
The EV indicator comes on when
the vehicle is driven using only the
electric motor (traction motor) or the
gasoline engine is stopped.
The on/off operation of the EV indi-
cator can be changed. ( P.166)
■After EV mode has switched to
HV mode due to low hybrid bat-
tery (traction battery) charge
If the hybrid battery (traction battery)
is regenerated by driving continu-
ously down a long slope, the EV
driving range etc. will be displayed
on the meter an d EV mode will be
automatically switched to.
If EV mode is not switched to even
though EV driving range is being
displayed, EV mode can be
switched to by pressing the EV/HV
mode selection switch.

792-1. Plug-in hybrid system
2
Plug-in hybrid system
■Gasoline engine operation in
EV mode or AUTO EV/HV mode
Even if there is a sufficient amount
of electricity remain ing in the hybrid
battery (traction battery) and EV
driving range ( P.155) is being dis-
played on the meter, EV driving
(driving using only the electric
motor) may be canceled and both
gasoline engine and electric motor
are used depending on the situation
(EV driving will be returned to auto-
matically after EV driving becomes
possible again).
EV driving may be canceled auto-
matically in the following circum-
stances
*1:
●When vehicle speed is more than
approximately 84 mph (135 km/h).
●When power is needed temporar-
ily, for example when the acceler-
ator pedal is depressed firmly or
when accelerating suddenly.
*2
●When the temperature of the
hybrid system is high.
The vehicle has been left in the
sun, driven on a h ill, driven at high
speeds, etc.
●When the temperature of the
hybrid system is low.
●When the heater is switched on
when the outside temperature is
below about 14°F (-10°C).
●When the windshield defogger
switch is pressed. ( P.434)
●When the system determines that
the gasoline engine needs to be
started.
*1: The gasoline engine may also
operate in circumstances other
than those listed above, depend-
ing on conditions.
*2: When driving in AUTO EV/HV mode. Even in EV mode, the gas-
oline engine may start, depend-
ing on the condition of the hybrid
battery (traction battery).
■If “Engine Started to Protect
System EV driving unavailable”
is displayed on the multi-infor-
mation display
EV driving may be canceled in order
to protect the hybrid system, etc.
In this case, perform driving with the
gasoline engine until EV driving will
be returned to automatically.
Depending on the conditions, driv-
ing that combines the use of the
gasoline engine may continue for a
short while. However, this is not a
malfunction.
■Conditions in which the gaso-
line engine may not stop
The gasoline engine starts and
stops automatically . However, it
may not stop automatically in the
following conditions
*:
●During gasoline engine warm-up
●During hybrid battery (traction bat-
tery) charging
●When the temperature of the
hybrid battery (traction battery) is
high or low
●When the windshield defogger
switch is pressed. ( P.434)
*: Depending on the circumstances,
the gasoline engine may also not
stop automatically in situations
other than those above.
■Sounds and vibrations specific
to a Plug-in Hybrid Electric
Vehicle
Because there is no engine sound
or vibration, it is easy to mistake the
Plug-in Hybrid Electric Vehicle for
being off when it is actually still run-
ning, as indicated by the “READY”
indicator being illuminated. For
safety, make sure to always shift the
shift position to P and apply the
parking brake when parked.
The following sounds or vibrations
may occur when the hybrid system
is operating and are not a malfunc-
tion.

802-1. Plug-in hybrid system
●Motor sounds may be heard from
the engine compartment.
●Sounds may be heard from the
hybrid battery (traction battery)
when the hybrid system starts or
stops.
●Relay operating sounds such as a
snap or soft clank will be emitted
from the hybrid battery (traction
battery), under the rear seats or
under the floor, when the hybrid
system is started or stopped.
●Sounds from the hybrid system
may be heard when the back door
is open.
●Sounds may be heard from the
transmission when the gasoline
engine starts or stops, when driv-
ing at low speeds, or during idling.
●Engine sounds may be heard
when accelerating sharply.
●Sounds may be heard due to
regenerative braking when the
brake pedal is depressed or as
the accelerator pedal is released.
●Vibration may be felt when the
gasoline engine starts or stops.
●Sounds may be heard from near
the hybrid battery (traction battery)
in accordance with the operation
of the air conditioning system or
battery cooler. ( P.109)
■Maintenance, repair, recycling,
and disposal
Contact your Toyota dealer regard-
ing maintenance, repair, recycling
and disposal. Do not dispose of the
vehicle yourself.
In order to make EV mode or
AUTO EV/HV mode available,
charge the hybrid battery (trac-
tion battery) from an external
power source before using the
vehicle.
Even if charging the hybrid battery
(traction battery) has not been com-
pleted, the vehicle can be driven.
However, if there is not enough
charge remaining, it is possible that
the vehicle cannot be driven in EV
mode or AUTO EV/HV mode or the
EV driving range will become
shorter.
■Refilling fuel
Plug-in Hybrid Electric Vehicles can
be driven using electricity charged
from an external power source.
However, as the gasoline engine is
used depending on the situation
(  P.79) even if in EV mode or
AUTO EV/HV mode, and the gaso-
line engine is provided on board as
a power source for driving in HV
mode, it is needed to refueling the
vehicle.
Check the fuel amount and refill
immediately when the fuel level
becomes low. ( P.279)
■If the vehicle is not used for a
long time
●The 12-volt battery may dis-
charge. In this event, charge the
12-volt battery. ( P.589)
In order to prevent the hybrid bat-
tery (traction batt ery) from becom-
ing extremely low in charge,
Charging ( P.94)