Chosen Solution
When turning on our Plasma Samsung TV model PN58A550S1F, it will revert to Air input, reflect a bluish snowy screen, then cycle off and back on. If I change the input to Component or HDMI, it will reflect a greenish screen with vertical lines. Sometimes the sound will come on as a high pitched constant beep. The only way to stop the cycle is to unplug it. I’ve tried unhooking all cables and it will still do this. I’ve tried hooking up one source component and testing it (component on the Wii, HDMI 1,2,3 on the Blue Ray and Xbox, different cords) and the result is the same. Yet, once in a while, it’ll show normal and work fine for a day or so.
Most likely a bad power board, but also could be the connections between the main board, or components on the main board. Check the power board and if it is good, then check the switching voltage regulator IC on main board (MP2363DNLF) and the 47 mfd capacitor. Try heating the IC to see if issue goes away, cool it and the issue returns. If so, replace the the IC and capacitor.
