Original topic:

75" Q7F Won't Boot

(Topic created: 10-04-2023 06:47 AM)
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userCKlkX0Db3K
Asteroid
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QLED and The Frame

Hello. I'm hoping someone out there can give me a new solution for my TV before it goes out to the dumpster. One day we turned it on, and it won't boot. The backlight comes on for a few seconds with no image, then goes off, red light blinks a few times, and then it does it again. Over and over, no matter how long its left connected. First, I tried all of the common answers online including leaving it unplugged, holding down the power button, combinations of button presses, etc. I opened it and disconnected ONE of the two image ribbon cables and found that the tv booted but with no image on EITHER half of the screen. But I know it booted because it would make sounds with button presses like the menu button and the backlight would stay on. This would be the case if I disconnected either (or both) of the ribbon cables. Once both ribbons were connected again, it would go back to boot looping. I also tried disconnecting the three backlight ribbon cables but again it stayed in the boot loop. I replaced the power supply board with a brand new one and it did the same. Finally, I replaced the motherboard with a used working board, same thing. I really hope someone is able to help me, otherwise it will probably be the last Samsung product I buy. 

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userCKlkX0Db3K
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I fixed it! I'm not a tv tech but I've been a pc tech for many years so I knew how to locate faults. I'm posting the fix here so that hopefully it could help someone somewhere with the same or similar problem.

As I mentioned in my original post, swapping the main board and power supply board made no affect on the problem so I assumed it had to be a bad panel as I didn't see any other boards I could test and replace. I also had assumed that the tcon board was built in to the main board as it had two ribbons coming out of it and in to the panel. What I didn't notice was that underneath a metal panel that runs along the bottom are 4 boards connected by ribbons that each drive a quarter of the panel. When I disconnected the right most board the TV started working again although with only three quarters of the image. Then I taped small portions of the ribbon until all of the screen was displayed with no artifacts or missing lines. I now have a fully working tv. I'll post pictures if anyone needs it.

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queenbabsbunny
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How long have you had it?
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userCKlkX0Db3K
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I bought it in December of 2018
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userCKlkX0Db3K
Asteroid
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QLED and The Frame
I fixed it! I'm not a tv tech but I've been a pc tech for many years so I knew how to locate faults. I'm posting the fix here so that hopefully it could help someone somewhere with the same or similar problem.

As I mentioned in my original post, swapping the main board and power supply board made no affect on the problem so I assumed it had to be a bad panel as I didn't see any other boards I could test and replace. I also had assumed that the tcon board was built in to the main board as it had two ribbons coming out of it and in to the panel. What I didn't notice was that underneath a metal panel that runs along the bottom are 4 boards connected by ribbons that each drive a quarter of the panel. When I disconnected the right most board the TV started working again although with only three quarters of the image. Then I taped small portions of the ribbon until all of the screen was displayed with no artifacts or missing lines. I now have a fully working tv. I'll post pictures if anyone needs it.
mike38
Constellation
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Would you mind posting some photos of what you taped off? I also am going through a very similar issue. I did replace 10 capacitors on the power board inside the TV that had some minor swelling hoping that would fix the problem, but no luck. I did just purchase a new main board (not here yet), but I’m concerned based upon your post that this may not be the issue.