Bose sound system not working
 

Hello, I'm new here so I'm hoping that I am posting in the correct area. I have a 2003 Silverado 2500hd ext can 4x4 LT with Bose sound system. A few years ago the head unit stopped working so I bought a harness and installed an aftermarket which worked fine but couldn't find an a wire that would turn it on/off with ign so I found two + wires from the harness and just connected them each morning(hey! It got me sound haha) anyway...... My buddy was installing a toggle switch for something completely unrelated and accidentally grounded out those positive wires and now my radio won't work. I checked the radio and amp fuse under the hood and they were fine. I'm getting 12volts into the amp but I'm not getting any voltage from the factory radio harness anymore. Is there a fusible link somewhere I could be missing? Could he have fried the amp? Any help would be greatly appreciated! Thanks