Toyota 2008 Prius Quick Reference Manual page 72

To disable smart key system
If you do not intend to drive your vehicle for a long time, push the can-
cel switch to deactivate the smart entry and start system.
KE Y
PRIUS_U_(L/O_0802)
1-3. Opening, closing and locking the doors and back door
Disabled
Enabled
ITY13P008
1
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