Phatty3dgar

I just recently bought my RX8 2004. There were no issues with it and all work was done at the dealer. The previous owner had a system installed and had an iPod connection directly installed into the factory stereo. It worked for the first few days and now it doesn't even turn on. Later on my A/C wouldn't turn on. The fan works but no lights in the dash work indicating that the compressor is turning on. I checked the fuses and they look good. Although some other wiring was done to install alarm and radio connections. Everything looks fine but can't seem to find why the radio or A/C don't turn on