Can be that someone was in the service manual. It's a shame too since the running advice is to never get into that since there is no document about this. I've heard folk that buy the service gripe the service menu is not documented.
As to the tapping like 1986 that points to board, panel or connection problems. Have your TV tech unplug, clean and plug in all connections. If it's a TAB BOND FAILURE, that on the panel is usually fatal.
I picked up this Samsung today, for a great price. owner moved it from Arizona to Oregon, when they put it on the wall they had lines on the left side of the TV. A tech was out and quoted them $2,400 to replace the panel, BN95-02001M. They opted for a new TV.
I got it home and it lit up perfectly. I thought I hit the jackpot. Then the left hand side started to flicker and get darker. I tapped the back of the panel like it was 1986 and it got better.....
Just now I was sitting here and it was dark, 7 minutes later it looks perfect. What's the deal? is it a bad panel or another component?
Yes, the screen is upside down.
https://photos.app.goo.gl/z6umsidUh1RL0asD2
https://photos.app.goo.gl/DWQezSbwrj00dfP63

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