Sorry to hear of your problems,

I had exactly the same situation in my Camry Hybrid... battery was completely dead every time the car was not used for more than about 48 hours. You can read the entire saga at this post:
http://www.greenhybrid.com/discuss/f...harging-12585/

After this happened about 6 times and the dealer had the car for a total of about 3 weeks checking battery drain in every circumstance (including at home in my garage) they found the problem. It seems that Toyota has notice several similar problems with the THC, all in the northern states, and they have tracked it down to a problem with the computer that controls the remote start. Apparently there is a malfunction between the smart key and the remote start program that is draining the battery over time. They installed new remote start controller/computer and that solved the problem. It’s never happened again.

If you dealer needs help, have them call the service manager at Maplewood Toyota, Maplewood Minnesota.

Hope this helps!