The following message is from a good friend of mine. I know enough about home audio to be dangerous but absolutely nothing about car audio. I was hoping someone could help me answer his question. Thanks in advance for any replies. First, a little bit about what I have...I have an F-150 crew cab w/ a two amp configuration. A four channel amp for the door speakers (Phoenix Gold) and a mono amp (Kenwood 8512D) for a single 10" sub (JL 10W6v2). The amps are mounted under the rear seat. This past weekend someone was riding in the back seat and managed to stick their foot under the seat and pull the negative speaker wire from the terminal on the sub amp. Initially I didn't know what had happened so I stopped the truck and checked it out. Being that I am very impatient and that I didn't have a screw driver in the truck I decided to use one of my keys on my key ring to re-tighten the terminal. Just before I have it tightened back down one of the other keys on the key ring happens to touch the power wire on the amp and it arcs. Following this...no amplifier power (power light is off). So the first thing that I did was check the main fuse on the power wire (it's ok), then the distribution block fuses (ok), and then the amp fuse (ok). So all of the fuses are good, the other amplifier works fine too, but the sub amp will not kick on. Does this mean that I "fried" the amp? Is there any kind of internal fuses in the amplifier? What do I need to do?