Toyota 2013 Prius C Owner's Manual page 449

Have the malfunction repaired immediately. (vehicles with a
smart key system)
After taking the specified steps to correct the suspected problem,
check that the warning message and light go off.
Interior Exterior
buzzer buzzer
⎯
Once
Warning message
(Flashes)
5-2. Steps to take in an emergency
Details
The electronic
key is not
detected when
an attempt is
made to start
the hybrid sys-
tem.
Correction
procedure
Start the hybrid
system with the
electronic key
present.
451
5