The AC, heater, radio completely stopped working completely, don't know why?

Check the ground and also make sure the wiring harness isn't frayed or cut.

Yeah, it will likely be a faulty connection or short on the steering column & actually shouldn't be too difficult at all. I watched my mechanic fix it in less than 10 min after I had him fix the ignition tumbler on the steering column after it wore down and literally wouldn't tumble to allow me to turn the key to even start it anymore! Anyway, I brought it in and the mechanic had to take the shroud off around the steering column to get at & change out the tumbler. So I guess he did this and "fixed it" & I went back to pay him an arm and a leg only to leave and realize 3 blocks later that my electronic temp control, radio and some other dash board features weren't working! I immediately turned around and went back and of course this mechanic tries to tell me that these dashboard features suddenly not working after he had just worked on an area that's literally connected to the dashboard, obviously must be a coincidence cuz he assured me that nothing he could of done could of possibly effected what was now broken! That or he even rudely tried to suggest that they may have been broken before I brought it in, essentially accusing me of trying to scam him! He was an asshole indeed. So, to prove to me what an idiot I am and to show that he didn't break my car, he starts removing the same pieces he initially removed to fix the first problem. Within minutes he gets off the steering wheel shroud and as he continues to fiddle with the area, suddenly as if by magic we hear the door alarm start beeping, then we see the radio turn on and the temperature control unit light up, only to watch it all suddenly go dark again before once more turning back on! Low and behold this bonehead caused a short when he was plugging the 2 wire harneses back into the steering wheel column! You probably just have to take those plastic pieces off that wrap around the column (it's like 3 or 4 screws,) and check those connections by disconnecting and then firmly reconnecting the 2 plugs while also inspecting the shape the wires are in. I bet if you play with them a bit the dash will even light up and off again like mine did. You probably could even do this without taking anything a part and just gently hitting or pushing on the column or by sticking something thin into the sides where the blinker switch is and moving it around until things start turning on, if so that's the issue. Incidentally, as he demonstrated that this only took him a few minutes to do, he also proved that he defrauded me because he initially charged me well over an hour in labour for replacing the tumbler! Smh... Good luck!