Check Hybrid System Prius 2010

Hey guys. Yesterday my Prius got a Check Hybrid System message. Along with it, check engine and triangle popped up as well. I an taking it to autozone and dealer later but I just wanted to possibly get some idea of what can be causing it. it has 220,000 miles. I noticed that when it came up it stopped using the hybrid system and was just using the gas the entire time. Did not lose any power though. The person I bought it from told me that this happened to him back in April and his mechanic disconnected the battery and it was fine up until now. I am about to take it to autozone but I was just trying to get possible issues with the symptoms it has. any help is appreciated. Thank you