Ground strap ?
 

I hope this is the correct place for this? On my 2002 Xtreme, in the back of the truck where the ground strap is mounted in the frame for the gas filler hose tube there is also another ground strap with a large white wire and a small black wire in the terminal. What is that ground strap for? I tried to trace it and can`t find where it goes.Thanks for any help on this.

That is a tough question. Have you put a meter on it yet?
Black is typically ground and white is power.

I would guess auxiliary lighting. Check for power with lights off/on.