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■When in HV mode
The vehicle can be used in the same way as a standard hybrid
vehicle.
In HV mode, controls are primarily carried out as follows in
accordance with the driving conditions.
●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. A l s o , w h e n n e c e s s a r y, t h e
electric motor (traction motor) operates as an electrical gener-
ator to charge the hybrid battery (traction battery).
●When the accelerator pedal is depressed heavily, drive force
from both the gasoline engine and the electric motor (traction
motor) is used to accelerate.
■When braking (regenerative braking)
The electric motor (traction motor) charges the hybrid battery
(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.
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PRIUS PHV_OM_OM47856U_(U)
Plug-in hybrid system control
The plug-in hybrid system features both EV mode and HV mode,
which are switched automatically. When a sufficient amount of elec-
tricity is remaining in the hybrid battery (traction battery) the vehicle
can be driven as an electric vehicle in EV mode; and when only a lit-
tle electricity is remaining in the hybrid battery (traction battery), HV
mode is automatically selected and the vehicle can be used in the
same manner as a hybrid vehicle.
The modes can also be switched using the EV/HV mode selection
switch. (→P. 3 7 )
■EV mode
Using the electricity stored in the
hybrid battery (traction battery),
the vehicle can be driven using
only the electric motor (traction
motor).
The gasoline engine may also be
used temporarily at the same
time in accordance with the
speed and load of the vehicle,
and with heater usage.
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PRIUS PHV_OM_OM47856U_(U)
■HV mode
If only a little electricity is remain-
ing in the hybrid battery (traction
battery) and the vehicle cannot
be driven using the electric
motor (traction motor) only, the
electric motor (traction motor)
and the gasoline engine will be
used together.
The Hybrid System Indicator can
be used to check which mode
the plug-in hybrid system is cur-
rently being driven in.
The EV drive mode indicator ( ) will illuminate when your vehicle
is in EV mode, and will turn off if HV mode is switched to.
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Charging (→P. 8 4 )
In order to drive in EV mode,
charge the hybrid battery (trac-
tion battery) from an external
power source before using your
vehicle.
If there is not enough charge
remaining in the hybrid battery
(traction battery), it is possible
that the vehicle cannot be driven
in EV mode or the distance that
can be driven in EV mode will
become shorter.
Vehicle proximity notification system
When driving with the gasoline engine stopped, a sound, which
changes in accordance with the driving speed, will be played in order
to warn people nearby of the vehicle’s approach. The sound will stop
when the vehicle speed exceeds approximately 15 mph (25 km/h).
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■Refilling fuel
Plug-in hybrid vehicles can be driven using electricity charged from an exter-
nal power source, however the gasoline engine that is provided on board as
a power source for driving in HV mode needs to be filled with fuel. Check the
fuel amount and refill immediately when the fuel level becomes low.
(→P. 1 7 8 )
■Gasoline engine operation in EV mode
Even if there is a sufficient amount of electricity remaining in the hybrid bat-
tery (traction battery) and EV driving range (→P. 5 8 , 2 7 0 ) i s b e i n g d i s p l a y e d
on the multi-information display etc., the gasoline engine may operate auto-
matically in the following circumstances (EV driving will be returned to auto-
matically after EV driving becomes possible again):
●When the heater etc. is in use.
●When the temperature of the hybrid system is high.
The vehicle has been left in the sun, driven on a hill, driven at high
speeds, etc.
●When the temperature of the hybrid system is low.
●When power is needed temporarily, for example when accelerating sud-
denly.
●When vehicle speed is more than approximately 62 mph (100 km/h).
●When the accelerator pedal is depressed firmly, the vehicle is driven up a
hill, etc.
●When the outside temperature is low (less than about 14 °F [-10 °C])
The gasoline engine may also operate in circumstances other than those
listed above, depending on conditions.
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PRIUS PHV_OM_OM47856U_(U)
■When continually using EV mode only
After driving for approximately 124 miles (200 km) with the gasoline engine
off, the gasoline engine may start for a short amount of time in order to pro-
tect the system.
■Conditions in which the gasoline 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
●When the temperature of the hybrid battery (traction battery) is high or
low
●During hybrid battery (traction battery) charging
●When the heater is switched on
*:Depending on the circumstances, the gasoline engine may also not stop
automatically in situations other than those above.
■If the vehicle is not used for a long time
The 12-volt battery may discharge. In this event, charge the 12-volt battery.
(→P. 5 9 7 )
In order to prevent the hybrid battery (traction battery) from becoming
extremely low in charge, start the hybrid system at least once every 2 or 3
months, and turn the “POWER” switch off after the gasoline engine has
stopped automatically. (If the gasoline engine does not start up even after
approximately 10 seconds have passed since the “READY” indicator came
on, the “POWER” switch can be turned to OFF without any further action.)
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■Sounds and vibrations specific to a hybrid vehicle
There may be no engine sounds or vibration even though the vehicle is able
to move. For safety, apply the parking brake and make sure to shift the shift
position to P when parked.
The following sounds or vibrations may occur when the hybrid system is
operating, and are not a malfunction.
●The brake system operation sound heard from the front of the vehicle
when the driver’s door is opened.
●Motor sounds may be heard from the engine compartment.
●Sounds may be heard from the hybrid battery (traction battery) behind
the rear seat when the hybrid system starts or stops.
●Sounds may be heard from the transmission when the gasoline engine
starts or stops, when driving at low speeds, or during idling.
●Engine sounds may be heard when accelerating sharply.
●Sounds may be heard due to regenerative braking when you press the
brake pedal or release the accelerator pedal.
●Vibration may be felt when the gasoline engine starts or stops.
●Cooling fan sounds may be heard from the air intake vent. (→P. 4 5 )
●The operation sound of the air conditioning system (air conditioning com-
pressor, blower motor).
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PRIUS PHV_OM_OM47856U_(U)
NOTICE
■Hybrid battery (traction battery) air vents
●Do not put foreign objects near the air vents. The hybrid battery (traction
battery) may overheat, leading to a reduction in hybrid battery (traction
battery) output or a malfunction.
●Clean the air vents regularly to prevent the hybrid battery (traction battery)
from overheating.
●Do not wet or allow foreign substances to enter the air vents as this may
cause a short circuit and damage the hybrid battery (traction battery).
●Do not carry large amounts of water such as water cooler bottles in the
vehicle. If water spills onto the hybrid battery (traction battery), the battery
may be damaged. Have the vehicle inspected by your Toyota dealer.
●If the rear seat belt becomes separated from the guide (→P. 1 5 4 ) , i t c o u l d
obstruct the hybrid battery (traction battery) air vent. Set the rear seat belt
into the guide to use.
■Notice about fuel
For plug-in hybrid vehicles, fuel may remain in the tank for a long time and
undergo changes in quality depending on the how the vehicle is used.
Refuel at least 5.3 gal.(20 L, 4.4 Imp.gal.) of fuel every 6 months (refuel a
total of at least 5.3 gal. [20 L, 4.4 Imp.gal.] over a 6-month period), as this
may affect components of the fuel system or the gasoline engine.