2000 Tahoe has about a 12 gage black wire coming out of the negative post with the large 2 gage grounding wire. My small 12 gage wire is broken off and I have no idea where it terminates. Any help?

That wire is grounded to the body. On my '98 Sub it's just behind the battery on the inside of the fender. Look for a bolt head that still has the terminal end of the broken wire.

Thanks for your reply. I'll look for the fender connection. I thought it went to the frame but was not sure if it had something to do with the 7 pin connector used for towing under the rear bumper. We have about 3" of new falling snow on the ground this morning so I'll get to it tomorrow. Thanks again.