My mom wanted Bluetooth and stuff so I bought her a Sony, installed it and it worked great but sound completely cut out after a few days. I returned and re installed but the same thing happened. I bought a pioneer thinking is a defect and installed new harness, soldered connections and tested with a multimeter. Everything worked great until the sound cut out a few days later.

What am I doing wrong?!

I've gone over the obvious but something wiring related seems to be frying these radios.

 

Something is probably wired wrong/shorting out.

We can't see how you wired it. What did you use to determine your colors?

 

I figured it out, the left rear speaker had chafed the wires down to the metal. I feel dumb now lol but now everything is kosher