My vizio p50hdm made a popping sound from the rear. Afterwards, the picture disappeared and tv screen was black (as if the power was off). Then within a minute the picture reappeared but looked real dull with a weird contrast. I disconnected power cord, turned off/on the tv, and the picture remains dull. Tv has been this way for almost a month. In order to repair, I have to pay an estimate of $600, including parts and labor. Please HELP!

Since you have some picture the Y-sustain and the buffer boards should be good especially if the fuses on the Y-sustain are still good. The Y-sustain is the larger board to the left looking from the back. Check the fuses on it. The buffer boards are the long two boards to the far left looking from the back of the set. If there is a blown fuse on the Y-sustain you must replace it AND both upper and lower buffer boards as well as the Z-sustain which is the larger board to the far right looking from the back of the set. Be sure to check the fuses in the Y-sustain before installing the Z-sustain. The part numbers should be on each board beginning like 6871... Since you have some picture the Y-sustain and the buffer boards should be good especially if the fuses on the Y-sustain are still good. The Y-sustain is the larger board to the left looking from the back. Check the fuses on it. The buffer boards are the long two boards to the far left looking from the back of the set. If there is a blown fuse on the Y-sustain you must replace it AND both upper and lower buffer boards as well as the Z-sustain which is the larger board to the far right looking from the back of the set. Be sure to check the fuses in the Y-sustain before installing the Z-sustain. The part numbers should be on each board beginning like 6871...