Starting problems - now with the car
Our five-year-old Prius has a problem with it’s battery. There are actually two batteries in the Prius; the large 230V battery used to power the electric motor as part of the hybrid drive and the regular 12V battery used to kick over the starter and power the accessories. This battery is charged from the bigger battery through an voltage shifting circuit.
If the 12V auxillary battery doesn’t hold a charge, then the accessories don’t work. Five years is about the life of that battery, so I’m not surprised that it’s gone now. Unfortunately, one “accessory” is the electronics to detect the key and start the hybrid engine. I don’t like that single point of failure, it’s bad design.
Another design problem is the location of this 12V battery. It’s under the trunk floor on the right side. Now if I can’t use the accesories, I can’t open the hatch at the back. I have to go in through the side door, flip down the seats, remove the truck cover, remove the trunk floor and anything stored in that area (all through the side door). Then I have to work in the small space to unbolt the hold ons and connections to that battery and lift it up and out of the space provided. All this makes a five-minute job into an hour or more.
While I’m generally pretty happy with the Prius they didn’t do well here.