@humbug the dark blue light etc. sounds like the backlight. I would start by unplug the TV by the power board and remove the back panel. Now unplug the cable from the power board to the main board. Then plug the power cord back into the power board. Do you see your backlight coming on through the little holes in the sheetmetal of the LCD panel?
If yes, then we know the issue is not a backlight and Samsung considers this a test for the power supply. Next you want to unplug the set again. Reconnect the main board. Connect the power back to your TV and turn it on. The you need a multimeter and measure the voltages on the connector for the main board cable. The expected voltages are printed on the board. Let us know what you get on those.
Also, take some good pictures of your boards and the complete backside of the TV. Post thoise with your Question. that will allow us to see what you see. It puts us all on the same page in the same book :-)
My suspicion right now, is a bad main board. It is your main board that tells the power board what to turn on. It tells the LCD panel when and what to display where. All very simplified of course. For now, just a suspicion and we need to check things out.
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Hi all, model UE50MU6120k I have the same issue as above, removed the back panel powered on i can see lights power on through the holes in the metal casing. Light stay on foe 2 seconds or so then go dim for 2 seconds the brighter for 2 seconds the appear to power off or rest for around 10 seconds. Any help please cheers
crwdns2934271:0crwdnd2934271:0 Rich crwdne2934271:0
My TV is Samsung.
Model Code: UA28F4000AKXKE
VERSION NO: LS01
S/N: LGDG3DCD600054N
crwdns2934271:0crwdnd2934271:0 Edward Haule crwdne2934271:0