2005 Toyota Prius MFD no ac or audio

So my old mfd unit was sayin “check the connection if the ac” when I press climate and audio just shows off not even on the steering wheel it turns on but when u press max ac on the wheel the ac blows. I replaced my unit thinking it would just be that since there isn’t any type of video or info on it besides soldering it down. I have a new unit from German audio tech and when I put it in he MFD was operating the same way. Is there any way I can get this problem fixed. It’s a no nav unit and I’m pretty sure my car is the no nav model. All my fuses are swapped and all connections look good. Anybody send me the right way on what to do next plz I need it asap