I had my system in my car for about 1.5 years and my alternator went twice already. Just last month my alternator died on me and it was just replaced last year. i am running a cheapo system consisting of 2 12" Rockford Fosgate XLC's in a bandpass box off of a 150x2 Crunch amp, 1 farad Rockford Cap, and a sony headunit. After my alternator died, i am kinda hesitant to put my fuse back in cause i'm worried there is some wiring problem. I don't usually crank it up super loud. My question is, when the fuse is in and the amp turn on wire is not connected, should there be voltage coming into the amp if i measured it from the power wire in the trunk?

 

the amp shouldn't be drawing any current from your electrical system is it's not turned on.

 

Well i'm not sure if it is actually drawing power but the positive main power wire does have voltage in it when i connect a voltage tester to the red wire and to the black ground. Is this normal? I would think it is since it is connected directly to the battery.