Prius Alarm System Battery Issue

I encountered a similar issue with my 2018 Opel Insignia. The symptoms were similar: a faulty alarm system and error messages. In my case, it turned out to be related to a weak battery. Do you experience any other electrical issues, like the car taking longer to start?

Thanks for the quick response! No starting issues or anything else obvious, just the alarm thing. Was your Opel showing a specific error code, or just a general alarm malfunction?

The Opel showed a general alarm malfunction error, nothing specific that pointed directly to the battery. Considering your Prius is also a hybrid, and batteries tend to degrade over time, it might be worth getting a professional to check the battery and the alarm system's power supply. It could save you from further electrical gremlins down the road.

Appreciate the advice. I took it to a shop, and you were right – the auxiliary battery was discharged due to age, messing with the alarm system. Cost me about 330€ to fix. Thanks again!