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731-1. For safe use
1
For safety and security
PRIUS c_U
Exhaust gas precautions
Harmful substance to the human body is included in exhaust
gases if inhaled.
WARNING
Exhaust gases include harmful carbon monoxide (CO), which is colorless and
odorless. Observe the following precautions.
Failure to do so may cause exhaust gases enter the vehicle and may lead to
an accident caused by light-headedness, or may lead to death or a serious
health hazard.
■ Important points while driving
● Keep the back door closed.
● If you smell exhaust gases in the vehicle even when the back do or is
closed, open the windows and have the vehicle inspected at your Toyota
dealer as soon as possible.
■ When parking
● If the vehicle is in a poorly ventilated area or a closed area, such as a
garage, stop the hybrid system.
● Do not leave the vehicle with the hybrid system on for a long t ime.
If such a situation cannot be avoided, park the vehicle in an o pen space
and ensure that exhaust fumes do not enter the vehicle interior .
● Do not leave the hybrid system operating in an area with snow build-up, or
where it is snowing. If snowbanks build up around the vehicle w hile the
hybrid system is operating, exhaust gases may collect and enter the vehi-
cle.
■ Exhaust pipe
The exhaust system needs to be checked periodically. If there is a hole or
crack caused by corrosion, damage to a joint or abnormal exhaus t noise, be
sure to have the vehicle inspected and repaired by your Toyota dealer.
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74
PRIUS c_U
1-2. Hybrid system
The illustration is an example for explanation and may differ from the
actual item.
Hybrid system features
Your vehicle is a hybrid vehicle. It has characteristics differ ent
from conventional vehicles. Be sure you are closely familiar wi th
the characteristics of your veh icle, and operate it with care.
The hybrid system combines the use of a gasoline engine and
an electric motor (traction motor) according to driving condi-
tions, improving fuel efficien cy and reducing exhaust emis-
sions.
Gasoline engine Electric motor (Traction motor)12
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751-2. Hybrid system
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For safety and security
PRIUS c_U
◆When stopped/during start off
The gasoline engine stops
* when the vehicle is stopped. During
start-off, the electric motor (traction motor) drives the vehic le. At
slow speeds or when traveling down a gentle slope, the engine i s
stopped
* and the motor is used.
When the shift lever is in N, the hybrid battery (traction batt ery) is
not being charged.
*: When the hybrid battery (traction battery) requires charging o r the engine
is warming up, etc., the gasoline engine will not automatically stop.
( P. 76)
◆During normal driving
The gasoline engine is predominantly used. The electric motor
(traction motor) charges the hybr id battery (traction battery) as nec-
essary.
◆When accelerating sharply
The power of the hybrid battery (traction battery) is added to that of
the gasoline engine via the ele ctric motor (traction motor).
◆When braking (regenerative braking)
The wheels operate the electric motor (traction motor) as a pow er
generator, and the hybrid battery (traction battery) is charged.
When the gasoline engine is off while driving, a sound is produ ced to
warn pedestrians, people riding bicycles or other people and ve hicles
in the surrounding area that the vehicle is approaching. The pi tch of
the sound adjusts according to v ehicle speed. When vehicle spee d is
approximately 16 mph (25 km/h) or more, the warning system turn s
off.
Vehicle Proximity Notification System
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761-2. Hybrid system
PRIUS c_U
■Regenerative braking
In the following situations, kinetic energy is converted to electric energy and
deceleration force can be obtained in conjunction with the rech arging of the
hybrid battery (traction battery).
● The accelerator pedal is released with the shift lever in D or B.
● The brake pedal is depressed with the shift lever in D or B.
■ EV drive indicator lamp
■ 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
● During hybrid battery (traction battery) charging
● When the temperature of the hybrid battery (traction battery) is high or low
● When the heater is switched on
The EV drive indicator lamp comes on
when the vehicle is driven using only the
electric motor (traction motor) or the gas-
oline engine is stopped.
This indicator lamp will also be dis-
played when “ECO Score” or “ECO
Savings” is selected. ( P. 103)
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771-2. Hybrid system
1
For safety and security
PRIUS c_U■
Charging the hybrid batt ery (traction battery)
As the gasoline engine charges the hybrid battery (traction bat tery), the bat-
tery does not need to be charged from an outside source. Howeve r, i f t h e
vehicle is left parked for a long time the hybrid battery (trac tion battery) 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). I f the hybrid
battery (traction battery) becomes fully discharged and you are unable to start
the hybrid system, contact your Toyota dealer.
■ Charging the 12-volt battery
P. 522
■ After the 12-volt battery has discharged or when the terminal h as been
removed and installed during exchange, etc.
The gasoline engine may not stop even if the vehicle is being driven by the
hybrid battery (traction battery). If this continues for a few days, contact your
Toyota dealer.
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781-2. Hybrid system
PRIUS c_U■
Sounds and vibrations sp ecific to a hybrid vehicle
There may be no engine sound or vibration even though the vehic le is able to
move with the “READY” indicator is illuminated. For safety, app ly the parking
brake and make sure to shift the shift lever to P when parked.
The following sounds or vibrations may occur when the hybrid sy stem is
operating and are not a malfunction:
● Motor sounds may be heard from the engine compartment.
● Sounds may be heard from the hybrid battery (traction battery) under the
rear seats when the hybrid system starts or stops.
● Relay operating sounds such as a snap or soft clank will be emi tted from the
hybrid battery (traction battery), under the rear seats, when the hybrid sys-
tem 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 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 or as the accelerator pedal is released.
● Vibration may be felt when the gasoline engine starts or stops.
● Cooling fan sounds may be heard from the air intake vent on the side of the
lower part of the rear left seat.
■ Vehicle Proximity Notification System
In the following cases, the Vehicle Proximity Notification Syst em sound may
be difficult for pedestrians, people riding bicycles or other people and vehicles
in the surrounding area to hear:
● When there is a lot of noise in the vicinity
● When it is raining or during strong winds
● When in the area surrounding the rear of the vehicle, rather than in front of
the vehicle
■ Maintenance, repair, recycling, and disposal
Contact your Toyota dealer regarding maintenance, repair, recyc ling and dis-
posal. Do not dispose of the vehicle yourself.
■ Customization that can be configured at Toyota dealer
Settings (e.g. the volume of Vehicle Proximity Notification System sound) can
be changed. (Customizable features: P. 558)
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791-2. Hybrid system
1
For safety and security
PRIUS c_U
The illustration is an example for explanation and may differ from the
actual item.
Hybrid system precautions
Take care when handling the hybrid system, as it is a high volt -
age system (about 520 V at maximum) as well as contains parts
that become extremely hot when the hybrid system is operating.
Obey the warning labels attached to the vehicle.
Warning label
Service plug
Air conditioning compressor
Electric motor (traction motor) Power control unit with DC/DC
converter
Hybrid battery (traction bat-
tery)
High voltage cables (orange)1
2
3
4
5
6
7
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801-2. Hybrid system
PRIUS c_U
There is an air intake vent on the
side of the lower part of the rear
left seat for the purpose of cooling
the hybrid battery (traction bat-
tery). When the air intake vent is
blocked, the battery operations
will be restricted and cause a
decline in fuel consumption.
When a certain level of impact is detected by the impact sensor , the
emergency shut off system blocks the high voltage current and stops
the fuel pump to minimize the ri sk of electrocution and fuel leakage. If
the emergency shut off system activates, your vehicle will not restart.
To restart the hybrid system , contact your Toyota dealer.
A message is automatically displ ayed when a malfunction occurs in
the hybrid system or an improper operation is attempted.
If a warning message is shown on
the multi-information display, read
the message and follow the
instructions. ( P. 485)
Hybrid battery (traction battery) air intake vent
Emergency shut off system
Hybrid warning message