Electric Vehicle Forums - Check hybrid system - "DC converter output low voltage"

Hi experts,
I have Toyota 2010 Prius and it showed "CHECK HYBRID SYSTEM" and engine light came on. Went to Autozone to check I have the error "DC converter output low voltage". I was to busy to come to dealer, so l let it stay home for 1 day. The next day I can't even start the car, all the light came on (engine, batt, break...) I checked on everything and found the 12v batt was low. I brought it to AutoZone to check, turned out the bad battery, bad cell so I bought the new battery. Now I can start the car but the "CHECK HYBRID SYSTEM" still on, with that error I cant go more than appx 40mph.

Please give me some advice on this. Many many thanks.