Pico fuses have nothing to do with your install...
I installed all my ish perfectly and my skateboard in my trunk ripped out some RCA's that weren't flush (my fault, but didn't have the wood), and there goes my pico fuse.
But, I do like my Pioneer HU, even though the Pico fuse is busted. You have to get creative. I managed to get mine to run with out problems. I
**** that pico fuse.. i just pull it out and put a fuse in there.