I would contact Gearbox on this. I had an error code when I tried to install mine. I called them and they told me to turn the key to the run position before I plugged in to the diagnostic port. I did and the programmer loaded.
I used a gear box before I got my sct and it came up with an error code. Cant remember the exact code but I called them and they sent me a new one over night and sent them the old one back. They will take care of you.