Chosen Solution
Model: UE32F5300AKXXU | Version No: 3Chassis: CY-HF320BGSV1HPanel: BN96-28700DPower Supply Board: BN44-00605ATCON Board: RUNTK 5361TPMain Board: BN41-01958B I am very positive (though I could be wrong) that it is a Power Supply Board Issue. The capacitors look fine and the rest of the board does too but The Backlight Doesn’t Turn On. The panel should be working correctly because I Did The Flashlight Test and There Is An Image. Also, when I disconnect the cable from the PS Board to the Main Board the backlight STILL doesn’t turn like it should. This leads me to believe this is Likely NOT a TCON or Main Board Issue. Also also, I have read a couple of posts about this issue that state that This may be a sign of Blown LED Backlight Assemblies, however I am highly doubtful of that since I have gotten this issue multiple times. If this was the issue, I should not have been able to fix it by just reconnecting wires. I checked the voltages on the CNM803 and they seem fine, but the CNL803 is a different story. All the pins give pretty much no voltage except for pin 12 which starts at 223V, slowly goes down to 196V and then comes back to 223V. This is very suspicious and is where I am stuck right now, I’m not sure what could be causing this or how I can fix it. If anyone could give me advice on how to fix this I would be very grateful. Also I know I could just replace the board but I would like to fix it myself if possible. Images:
Update (12/29/2019) Good news! turns out the problem was a diode on the PS Board but it’s a very easy fix, just had to replace it and now the tv works great.
Hi @peterplaczek , If you have high voltage on the backlight cable connector on the power board and no backlights are on there is an open circuit between the power board and or in the backlight array. The voltage is being driven high trying to turn on the LEDs You’ll have to track the cable to where it connects to the backlight array and start checking for continuity to see where the open is. It may be that there are some faulty LEDs causing the open circuit or a faulty connection on the pcb that the LED array and the cable from the power board connects to. Not totally sure if your model has this small pcb but the cable from the power board connects to the array somehow Here’s a video that may help
