If 12v battery is dead, how do you get in the car?

Dead Battery, car won't open | PriusChat

 

There is a valet key on the side of the fob you can slide out and unlock the door.
Then use the jump start terminal inside the engine compartment fuse box to jump start, but be very careful to follow the instructions in the owners manual. You can cause a lot more expensive damage doing it incorrectly or using a source with too many amps. If it's the original 12-volt, probably just ought to replace it.

 

The number of amps available has no bearing on the safety of jump starting the Prius. Connecting with reverse polarity is the number one enemy, and liable to cause maximum damage. It is also advisable not to have the downer jump engine running, this is because alternators can give out high voltage spikes, not good for the Prius electronics.

John (Britprius)