ok i just installed my subs. I wired the whole amp turned it on and nothin. so i checked all the conections, i know the amp is getting power but the little led light isn't coming on. i figure i have a bad ground and after trying several places i'm stuck. so i was wondering where do you ground your amps?

 

grounded to tail light panel under t top hook

 

Don't be so sure that it's a ground. The ground must be REALLY bad if the amp isn't even turning on. Just touching a small piece of wire to a clean spot on the chassis should be a sufficient enough ground just to turn on an amp. Did you actually verify that you have 12 volts at the amp power terminal, or are you just assuming because you wired it? I've seen people forget to install the fuse into the holder then rip their hair out trying to figure out why they don't have any power at the amp. Assuming that you do actually have 12 volts at the amp terminal, did you power the remote turn-on terminal on the amp? The amp won't turn on just because it has 12 volts and ground. You need to supply 12 volts to the remote lead, which powers an internal relay connected to the main power feed.

Assuming that all checks out, you should follow some basic grounding practices:

First, you should make sure you have an adequate wire size for the ground. It should be just as big as the power wire.

Second, you should have a solidly connected ring terminal on the end of the ground wire. Solder, crimp, whatever. Make sure it's sturdy.

Third, you should be using a pre-existing bolt & hole, a pre-existing stud & nut, or installing your own bolt & nut. Point is, it needs to have a solid attachment point that you can actually tighten. Driving a self tapping screw through some sheet metal doesn't cut it.

Lastly, you need to scrape the area of attachment around the hole/stud to bare metal to ensure that your connector is in contact with metal and not paint/primer. For good measure, I always put a star washer between the ring and the connecting point to make it absolutely certain that there is good conduction.