I have done a lot of research on this issue and see others have had similar/same issue and I don’t see resolution.
My 2008 Prius was totally dead about a month ago for no apparent reason after I had just driven it 2 hours before. I had it jumped and all was well. 3 weeks later I let the car sit a week while out of town and car was dead again, no lights no clicking of alarm just completely dead. I had it jumped again, drove it 30 min and when I turned it off it was dead again. THEN the car came back to life on its own in the driveway, engine in and alarm blaring. Got it to a shop next day and it died at shop. They said it was an alarm issue. Took it to dealer. They said it was alarm issue. Had alarm removed and drove it for an hour, started fine, the 45 min later dead again! Had it jumped again. Took it to new repair shop and they said it’s my hybrid battery. I did my own research and realized that thy hybrid battery does not start the car. So I get it back to dealer, alarm removed and ask them to diagnose. 2 days later they say car is starting fine, no issues found. So I pick up my car, they drive it to me, I turn it off, it’s dead again! This time I see door ajar light on and can hear door lock and unlock with remote so it has some power. They did an immediate battery test. Battery tested fine and healthy. Car is still at dealer and they seem stumped as I am and really don’t want to scrap a Toyota with 137,000 miles that’s been so reliable and I’ve maintained it very well. I have 2 young kids and can’t afford to keep getting stranded!
Has anyone found the cause as I’ve seen other people have the same issues?