2007 hybrid loses electrical power, using manual key on door, power returns

Are you plugging the electronic key into the slot to start the car? If it won't work wirelessly, the keyfob battery could be dead. Otherwise it sounds like your 12v battery is bad and not holding charge well. It should easily hold charge for three weeks well enough to power the electronics. Take it to an auto supply and have them load test it. Finally, the hatch light may not be going off, sometimes caused by incomplete closure of the hatch.

 

When this happens, open the hood and use a digital multimeter to check the voltage at the jump start post (I use the stud/nut for the strut mount close by as my ground point). If you have less than 12.4 to 12.6V then next step is to test at the battery (yes, that's tough when you can't open the hatch). If the battery is the same low voltage then it should be charged and tested. Might be a faulty battery. If voltage is higher than at the jump point then you have a bad/ loose connection somewhere.

Posted via the PriusChat mobile app.

 

12 V battery going bad OR a bad main cable connection to same.
Get the battery tested.......or if it is over 5 years old, just replace it.