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2 Samsung UN55F6300 Power Cycle Issue
I'm trying to fix my parent's tv and having difficulties finding out the problems with this Smart TV.
It's having a power cycle issue. Sometimes it stays a little longer if I have some video contents playing through third HDMI input (about 5 minute or less) but most of the time it just power cycles itself after Samsung Smart TV boot logo, black screen, restart. The remote control doesn't work other than the power button (I have to hold it down a little long to turn tv on with it). The joystick behind the TV can only turn TV on when it wants to, can't access the setting menu, can't change video source, can't do anything else just as useless at the remote control. It can only accept video source from 3rd HDMI input.
I tried unplugging T-Con connector, issue still there, I also tried unplugging Wifi connector, IR/Joystick cable but none fixed the power cycle issue.
If I unplug the Power cable to main board connector, backlight will stay on. I also checked the voltage reading from power board and got constant around 12v and none of the capacitors/transistors showing any sign of bulging or burned out.
Could it be the main board that is causing the power cycle? Has anyone fixed a F6300 series? What are the common issues with main board failing on these Samsung Smart TV?
Here's the suspected main board: BN94-07217F Main Board for UN55F6300AFXZA (WH04)
Any help is greatly appreciated. I don't really want to take it to the repair shop and spend more than what it is worth. My parents don't even care anymore, already got their old CRT tv out lol.
Update (04/19/2018)
I can't get to the setting menu with the remote or the joystick behind the tv to updat the firmware lol and even if I could the TV doesn't stay long enough to let me update the firmware.
I tried to hard reset the main board but it didn't help, same issue still there.
Pic of Power Board
Pic of Main Board
@animex this sounds more like a power board issue than a mainboard issue. Have you checked all the outputs on CNM803 as well as CNL802? the voltages you need to have on the individual pins are marked on the boards. Post some images of all of your boards with your question. Use this guide 在已经存在的问题里加入图片 for that so that we can see what you see.
由 oldturkey03 完成的
Didn't know there is an option for adding picture. haha. Thank you! I will try to check the outputs on those 2.
由 animex 完成的
Sorry for the bad quality of the picture. I added a snapshot from the other website.
由 animex 完成的
I’ve got the same problem, starting to think Samsung is $@$*
由 John Franks 完成的
I have upgraded the firmware and replaced the power board and the problem persists. Mine will operate for about 2 minutes before it restarts.
由 JC Dufresne 完成的
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