If you have a light on the LNB, I think that was only present on older Sony branded dishes (white colored). That being said, I have no experience with this dish so I am just pulling suggestions out of my ass.

I assume the light on the LNB should be lit all the time. The LNB gets its power from the DirecTV receiver (5V IIRC). If the light is not constanly lit, I would assume it is not getting power from the receiver. This would indicate a cabling problem. Are you using quad-shielded RG6 by any chance? This seems to be all Home Depot is selling lately. I've had bad crimps on the quad shielded before. I would check that first. Even though it looks like a good crimp, it may not be making a proper connection.

[rant]I don't know why they don't stock double shielded any more. Much easier to manage and much easier to make a proper crimp with their cheap F connectors.[/rant]