Doing the manual selection pointing only proves that the center 119 LNB is working. It uses that one only even though you pointed at 3 different satellites. The LNB or cables from the LNB could be bad. Checking the cable(s) inside the arm down to the base would be a worthwhile project. You also need to disconnect each coax cable end (F connectors) and inspect for corrosion. Each end should have had a dab of dielectric grease to prevent this.
Turning power off to the Winegard controller does not shut down power to the antenna. The power for the LNB comes from the Hopper IIRC. Mine is connected to a DTV Genie.
