Toyota 2008 Prius Quick Reference Manual page 54

When stopped/during take-off
n
The gasoline engine stops when the vehicle is stopped. During
take-off, the electric motor (traction motor) drives the vehicle. At
slow speeds or when traveling down a gentle slope, the engine
is stopped and the motor is used.
During normal driving
n
The gasoline engine is predominantly used. The electric motor
(traction motor) charges the hybrid battery (traction battery) as
necessary.
When accelerating sharply
n
The power of the hybrid battery (traction battery) is added via
electric motor (traction motor) to that of the gasoline engine.
When braking (Regenerative brake)
n
The electric motor (traction motor) charges the hybrid battery
(traction battery).
Regenerative braking
n
The motor generator converts kinetic energy to electric energy when:
The accelerator pedal is released.
l
l The brake pedal is depressed with the shift lever in "D" or "B".
Conditions in which the gasoline engine may not stop
n
The gasoline engine starts and stops automatically. However, it may not stop
automatically in the following conditions:
l The gasoline engine is warming up.
The hybrid battery (traction battery) is being charged.
l
l The hybrid battery (traction battery) temperature is low or high.
PRIUS_U_(L/O_0802)
1-1. Hybrid system
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