I have a Prius 2004 bought used 2 years ago. The 12v battery keeps dying. I changed the battery twice, with the last one installed in a few weeks ago, and since then the most I have left the car parked without driving it has been around a week. Yet this last battery is already weak and failed me three times. At this point there is no redeeming chance for it I suppose.
Any tips appreciated on what could be happening. My mechanic skills are limited but I should be able to follow instructions.