I took the stock radio and tape player out of my truck to put a new cd player in, But when I took it out there were two wiring harnesses in the back of the old one. My new one only has one wiring harness that comes out of the back. Which one of these am I supposed to hook to? Can you leave one just hanging there? What is the second harness for anyway?

 

I'd suggest that you go buy an adaptor. $15 at walmart, bb, cc, radioshack... this way you will see that you will use Both harnesses!