Corolla Hybrid electrical malfunctions

I had a similar situation with my Corolla Hybrid. The error message and starting issues sound familiar. Have you checked the auxiliary battery's voltage? In my case, a faulty voltage regulator wasn't letting the battery charge properly. I had similar electrical issues and weak battery performance, though I didn't see any stored errors. It might be worth looking into the charging system components.

Thanks. Can you give me more detail on how you knew it was the voltage regulator, and what you did to fix it? Did you replace it yourself, or take it to a professional?

I thought it was the battery at first, but testing showed it was holding a charge, just a low one. After more tests, including checking the voltage regulator's output, it was clear it wasn't providing enough voltage to keep the auxiliary battery charged. Because the hybrid system is complex, and I don't have much experience with those parts, I took it to a trusted workshop for repair. I suggest you do the same.

Thanks for the explanation and advice. I'll take it to a workshop for a checkup. The estimated repair cost is around 290€. Hopefully, it's an easy fix. Thanks again for sharing your experience; it's been really helpful.