youngblood

i have been trying to hook up my comand 2.0 unit to a tv tuner. do i need to hook up the a,b, and c into to tv tuner or hook a and b into the comand and c into the tuner. also on the tuner harness i don't know which color pins goes oon which number? i know the number of the pins for a, b, c1 and c2 already. does anyone have a diagram they could send me for the entire hook-up? also where is a good place to ground the tuner? i tried hooking up a and b into the tuner and it made a loud noise without the car on. so i pulled it out quickly. i don't know if that was a good or bad thing.