TOYOTA PRIUS 2012 3.G Owner's Guide

31
1-1. Hybrid system
1
Before driving
■
When stopped/during start off
The gasoline engine stops
* when the vehicle is stopped. During
start off, the electric motor (tra ction motor) drives the vehicle. At
slow speeds or when traveling down a gentle slope, the engine
is stopped
* and the electric motor (traction motor) is used.
When shift position is in N, the hybrid battery (traction battery)
will not be charged. Thus, shift to P when the vehicle is stopped.
In addition, when driving in heavy traffic, use D or B.
*: However, when the hybrid battery (traction battery) need to be charged or while the engine is being warmed up, the gasoline
engine may not stop automatically. ( P. 33)
■ During normal driving
The gasoline engine is predominantly used. The electric motor
(traction motor) charges the hybr id battery (traction battery) as
necessary.
■ When accelerating sharply
When the accelerator pedal is depressed heavily, the power of
the hybrid battery (traction battery ) is added to that of the gaso-
line engine via the electric motor (traction motor).
■ When braking (regenerative braking)
The electric motor (traction mo tor) charges the hybrid battery
(traction battery).

32 1-1. Hybrid system
Vehicle proximity notification system
When driving with the gasoline engine stopped, a sound, which
changes in accordance with the dr iving speed, will be played in order
to warn people nearby of the vehicle’s approach. The sound will stop
when the vehicle speed exceeds a pproximately 15 mph (25 km/h).
■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 battery (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.
■ Hybrid System Indicator
Hybrid System Indicator represents the
hybrid system power output and regener-
ative charging. (
P. 225)

33
1-1. Hybrid system
1
Before driving
■
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.
■ Charging the hybrid battery (traction battery)
●As the gasoline engine charges the hybrid battery (traction battery), the
battery does not need to be charged from an outside source. However, if
the vehicle is left parked for a long time the hybrid battery (traction bat-
tery) will slowly discharge. For this reason, be sure to drive the vehicle at
least once every few months for at least 30 minutes or 10 miles (16 km).
If the hybrid battery (traction battery) becomes fully discharged and you
are unable to jump-start the vehicle with the 12-volt battery, contact your
Toyota dealer.
● If the shift position is in N, the hybrid battery (traction battery) will not be
charged. Always shift the shift position in P when the vehicle is stopped.
When driving in heavy traffic, operate the vehicle with the shift position in
D or B to avoid discharging the hybrid battery (traction battery).
■ Charging the 12-volt battery
P. 546
■ After the 12-volt battery has di scharged or has been changed or
removed
The gasoline engine may not stop even if the vehicle is running on the hybrid
battery (traction battery). If this continues for a few days, contact your Toyota
dealer.

34 1-1. Hybrid system
■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) 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 the brake pedal
is depressed and accelerator is loosened.
● Other sounds, such as motors and mechanical noises, may be heard
from the brake system when the brake pedal is depressed.
● Vibration may be felt when the gasoline engine starts or stops.
● Cooling fan sounds may be heard from the air intake vent. (
P. 37)
● The operation sound of the air conditioning system (air conditioning com-
pressor, blower motor).

35
1-1. Hybrid system
1
Before driving
■
Vehicle proximity notification system
In the following cases, the vehicle proximity notification system may be diffi-
cult for surrounding people to hear.
●In very noisy areas
● In the wind or the rain
Also, as the vehicle proximity notification system is installed on the front of
the vehicle, it may be more difficult to hear from the rear of the vehicle com-
pared to the front.
■ Maintenance, repair, recycling, and disposal
Contact your Toyota dealer regarding maintenance, repair, recycling and dis-
posal. Do not dispose of the vehicle yourself.

36
1-1. Hybrid system
Hybrid system precautions
Take care when handling the hybrid system, as it contains a high
voltage system (about 650V at m aximum) as well as parts that
become extremely hot when the hy brid system is operating. Obey
the caution labels attached to the vehicle.
Air conditioning compressor
High voltage cables (orange)
Power control unit and DC/
DC converter
Caution labelService plug
Electric motor (traction
motor)
Hybrid battery (traction bat-
tery)

37
1-1. Hybrid system
1
Before driving
Hybrid battery (traction battery) air vent
There is an air intake vent on the
right side of the rear seatback for
the purpose of cooling the hybrid
battery (traction battery). If the
vent becomes blocked, the
hybrid battery (traction battery)
may overheat, leading to a
reduction in hybrid battery (trac-
tion battery) output.
Emergency shut off system When a certain level of impact is detected by the impact sensor, the
emergency shut off syst em blocks off the high voltage current and
stops the fuel pump to minimize t he risk of electrocution and fuel
leakage. If the emergency shut off sy stem activates, your vehicle will
not restart. To restart the hybrid system, contact your Toyota dealer.
Hybrid warning message
A message is automatically displa yed when a malfunction occurs in
the hybrid system or an impr oper operation is attempted.
If a warning message is shown
on the multi-information display,
read the message and follow the
instructions. ( P. 507)

38 1-1. Hybrid system
■If a warning light comes on, a warn ing message is displayed or the 12-
volt battery is disconnected
The hybrid system may not start. In that case, try to start the system again. If
the “READY” indicator does not come on, contact your Toyota dealer.
■ Running out of fuel
When the vehicle has run out of fuel and the hybrid system cannot be
started, refuel the vehicle with at least enough gasoline to make the low fuel
level warning light ( P. 498) go off. If there is only a small amount of fuel,
the hybrid system may not be able to start. (The minimum amount of fuel to
add to make the low fuel level warning light go out is about 1.9 gal. [7.1 L,
1.6 Imp.gal.], when the vehicle is on a level surface. This value may vary
when the vehicle is on a slope.)
■ Electromagnetic waves
●High voltage parts and cables on the hybrid vehicles incorporate electro-
magnetic shielding, and therefore emit approximately the same amount
of electromagnetic waves as conventional gasoline powered vehicles or
home electronic appliances.
● Your vehicle may cause sound interference in some third party-produced
radio parts.
■ Hybrid battery (traction battery)
The hybrid battery (traction battery) has a limited service life. The lifespan of
the hybrid battery (traction battery) can change in accordance with driving
style and driving conditions.

39
1-1. Hybrid system
1
Before driving
CAUTION
■
High voltage precautions
The vehicle has high voltage DC and AC systems as well as a 12-volt sys-
tem. DC and AC high voltage is very dangerous and can cause severe burns
and electric shock that may result in death or serious injury.
●Never touch, disassemble, remove or replace the high voltage parts,
cables or their connectors.
● The hybrid system will become hot after starting as the system uses high
voltage. Be careful of both the high voltage and the high temperature, and
always obey the caution labels attached to the vehicle.
●Never try to open the service plug
access hole located in the luggage
compartment. The service plug is used
only when the vehicle is serviced and is
subject to high voltage.

40 1-1. Hybrid system
CAUTION
■Road accident cautions
If your vehicle is involved in an accident, observe the following precautions
to reduce the risk of death or serious injury:
●Stop the vehicle in a safe place to prevent subsequent accidents.
While depressing the brake pedal, apply the parking brake, shift the shift
position to P and turn the hybrid system off. Then, slowly release the brake
pedal.
● Do not touch the high voltage parts, cables and connectors.
● If electric wires are exposed inside or outside your vehicle, an electric
shock may occur. Never touch exposed electric wires.
● If a fluid leak occurs, do not touch the fluid as it may be strong alkaline
electrolyte from the hybrid battery (traction battery). If it comes into contact
with your skin or eyes, wash it off immediately with a large amount of water
or, if possible, boric acid solution. Seek immediate medical attention.
● If a fire occurs in the hybrid vehicle, leave the vehicle as soon as possible.
Never use a fire extinguisher that is not meant for electric fires. Using even
a small amount of water may be dangerous.
● If your vehicle needs to be towed, do so with front wheels raised. If the
wheels connected to the electric motor (traction motor) are on the ground
when towing, the motor may continue to generate electricity. This may
cause an electricity leakage leading to a fire. ( P. 485)
● Carefully inspect the ground under the vehicle. If you find that liquid has
leaked onto the ground, the fuel system may have been damaged. Leave
the vehicle as soon as possible.
■ Hybrid battery (traction battery)
Your vehicle contains a sealed nickel- metal hydride battery. If disposed of
improperly, it is hazardous to the environment and there is a risk of severe
burns and electrical shock that may result in death or serious injury.