My stereo won't cut on

What kind of radio is it?

Is there a fused link to the radio? Does the radio have an internal circuit breaker or fuse?

I tested the radio it works. But you no grand prix has that special wiring kit, it has some kind of capacitor on it. I'm wondering if that's bad???

If you got a spark from your ground lead, it probably touched a 12v source and could have easily blown a fuse. Had the radio been operating in the car before this happened or were you just then doing the install?

I have the same problem with a 2004 grand am. there is power coming to the radio, but no display or sound. I remember the same problem with the saturn sc series and it turned out to be another relay to do with the audio system.these grand ams have security problems and that could be the problem.