does the 8" subs in the door have a separate fuse for the amp? I installed the shelby (kicker) subs...maybe a year ago and now the subs stopped working.

 

I would check the stock amps, cause I pretty sure there not rated to handle the kicker subs. Yeah It could be a fuse in the amp. I would alo suggest if you cant find out why they stoped working, then look for a new amp to power them.