Prius Key Battery Low

I had a similar problem with my Prius, though I don't remember the error memory part. Does the key work if you hold it next to the start button?

Thanks! No, holding the key next to the start button doesn't work. It's unresponsive. I can only start the car by using the physical key to unlock the door and then holding the fob against the start button. Did you have the same experience?

Yes, that was exactly it. The car wasn't detecting the key unless it was touching the start button. I'd advise a local workshop. They'll likely say it's the key fob battery, a quick and cheap fix. But they can check for other problems and confirm the error codes.

Okay, I appreciate the advice! Sounds like our experiences were identical. I'll get it checked. Just got back, and you were right, the key fob battery was dead. Replacing it fixed everything. Repair cost was 37€.