I have a pioneer deh-p3600 cd player in my car and it recently stopped working. It would go on and off when I drove around after hitting bumps and such but now it doesn't work at all. Any suggestions.

Pull it out and look for poor connections. maybe wasnt installed correctly and wire connections are breaking loose and or touching metal, tape up all connections and if problem is still there check all wiring for insulation missing and tape that area up , also make sure black wire(ground) is securely bolted down to metal!