Can you please elaborate on Tuner A is Blue.
What satellite is your motorized dish pointing at?
Try changing your tuner setting to simple, single satellite, selecting the satellite, and do a manual scan, of that satellite.
Also check your cable connection, different receivers might require different amount of copper, to get a signal, and ensure the braid is done correctly.
You state you have tried a different receiver, on your set up, and it wiorks, so you know the dish, able, LNB are all working, so if the problem isn't the receiver software it's a good chance the tuner, or other component, has failed.