Chosen Solution
Hey guys, TV took a crap on us. First symptoms were flickering during startup but afterwards the TV would work fine until at some point the brightness just dipped to a very low level (although I do think the backlight still works, I’ll check soon). Additionnally the TV does some weird flickering when screwing around with the brightness settings. Clips of the test image and the flickering when adjusting brightness setting: https://imgur.com/a/DaHgkg3 The led strips themselves and the backlight seem to still work. Which of the boards is most likely to be done? I’m fine with ordering and replacing a board. Don’t really have any experience or the tools to check voltages over some components. TV is a Samsung UE55JU6400K.
Hi, When the screen goes black shine a torch at an angle close to the screen and check for images. They will be very faint so trying this in a darkened room may help to see them if they are there. Try the following to check if the backlights do work properly. Be safety aware if you decide to try this as there is exposed lethal AC voltage and also high DC voltage on the power board in the TV when the power is applied to the TV Turn off the TV if on and disconnect the power from the TV. Remove the back cover from the TV and then disconnect the cable between the power board and the mainboard. Reconnect the power to the TV. The backlights should turn on full intensity and stay on. There will be no picture because the mainboard is disconnected. Disconnect the power from the TV before doing any more work in the back of the TV If the backlights don’t turn on or they flicker, blink etc then there is a problem either on the power board, the connections between the power board and the LED strips or the LED strips themselves. If the backlights do stay on then there may be a problem on the power board or the mainboard. You will need a DMM (digital multimeter) and know how to use it safely when testing for the voltages, to know where the problem may be as otherwise it is only guessing. The above test was only to isolate the problem one way or the other i.e. mainboard or power board OR power board or LEDs
