Toyota Prius Owner's Manual page 314

2-4. Using other driving systems

Hill-start assist control
P. 318

PCS (Pre-Crash Safety System) (if equipped)
P. 321

Emergency brake signal (if equipped)
When the brakes are applied suddenly, the stop lights automati-
cally flash to alert the vehicle behind.
When the TRC/VSC/ABS systems are operating
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The slip indicator light will flash
while the TRC/VSC/ABS sys-
tems are operating.