Hello everyone, I hope you had a happy Thanksgiving! This TV comes from the free pile. It's a Samsung PN59D550C1FXZA. The complaint was the previous owner was watching TV, they heard a buzz/pop and lost video with audio present. After trying to re-boot the TV it appears to wake-up but isn't responding to the remote or key controls. No picture and no response to commands are confirmed.
The health light indicated a problem on the sustain boards with a very long on-time when flashing. The main cap voltage comes up when plugged in then immediately drops off, so do VS and VA. I Tested the Y-sustain for VS short to ground, none present then tested the X-sustain for same. VS is shorted to ground on the X-Sus board. When removing the X-Sus the screws were all loose, and after inspecting the ground pads and chassis contact points there is evidence of arcing. Both sustain boards have loose screws right along with the PSU.
The bank of FET's circled all indicate short and are right by the output header connectors to the X-buffer.
The conclusion I have drawn by this is the poor ground plane and evidence of arcing grounds on the X-Sus board is probably what popped the FET's.
The question I have, is there another possible explanation for the popped FET's, such as a short in the panel itself or maybe the lousy "D" series panel cracked and took them out?
Thanks everyone for your input!
The health light indicated a problem on the sustain boards with a very long on-time when flashing. The main cap voltage comes up when plugged in then immediately drops off, so do VS and VA. I Tested the Y-sustain for VS short to ground, none present then tested the X-sustain for same. VS is shorted to ground on the X-Sus board. When removing the X-Sus the screws were all loose, and after inspecting the ground pads and chassis contact points there is evidence of arcing. Both sustain boards have loose screws right along with the PSU.
The bank of FET's circled all indicate short and are right by the output header connectors to the X-buffer.
The conclusion I have drawn by this is the poor ground plane and evidence of arcing grounds on the X-Sus board is probably what popped the FET's.
The question I have, is there another possible explanation for the popped FET's, such as a short in the panel itself or maybe the lousy "D" series panel cracked and took them out?
Thanks everyone for your input!
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