86 Cadillac Sedan Deville stereo wiring question, Big black wire?

[Joe]

I'm replacing the stock stereo in my '86 Cadillac Sedan Deville with a new aftermarket stereo. There is a thick black wire that has its own plug-in on the back of the stock deck, what the hell does this do? I'm at a loss as to what this thing is even for...I probably wont even need it.

The link below says that the constant, switched, ground, and illumination are Black, Grey, Yellow, and Orange... but there is only Black, Grey, Yellow, and Yellow w/Black stripe. is Yellow w/Black stripe probably constant 12v?

Also, there is a constant 12v source and a switched 12v source. Is the switched 12v basically the one that runs to the fuse box so that the deck turns off when the car turns off? I've installed a few stereos before and know what I'm doing for the most part, but this is unclear to me. Just asking before I go and f*** something up...The last stereo was kinda jimmy-rigged into the car and I'd rather do a good job since this car has a nice clean interior and is also getting subs at the same time (which I have no problem doing, subs are simple compaired to this cluster). Your help is greatly appreciated.

Thanks!

http://www.the12volt.com/installbay/stereodetail/432.html
Thick black wire

http://tinypic. com/r/e9svvn/6
Site wouldn't let me post a link, so be aware there is a space before "com"

 

[Karle1]

ur'e either talking about the ground wire which in a lot of cases there are 2.....1 big and 1 smaller and yes the radio will work with just the smaller hooked up but the bigger is there as back up and to keep the radio form burning up


the other thing it could b would b the stereo antenna.......if u don't recognize this then u shouldn't b installing a radio to start with......

btw how a about a link with a picture of the wire so could tell u for sure....