HP Tuner ?? (Yes I searched..........for hours)

I just bought HPtuners Pro yesterday, got it all up and ready to go. For about the last 7 hours I have been trying to get it to communicate to the truck. Here is what I did.

I wired the LS1 engine seperate from the rest of the truck, being that the 04' Colorado was originally PCM/BCM tied together working in tandem. I did not touch anything in the BCM at all, now when I tried to start it several weeks ago It locked up. (security light, VATS??) So I tried to use my HPTuners and my Snap On scanner, and neither one of them could communicate with the PCM, but yet I could scan and read codes in the BCM. I do have a U1000 code now, which I think Is why I can't get it to communicate.

How do I get my tuner to read it??