I've yet to see TV engineers offer repair advice except to tell folk to get the service manual and follow along. That is, guessing is usually not working. It's back to the manual and swap what it tells you.
I have a 60# Samsung TV, UN60FH6003F. I suddenly lost the pic & sound. TV 4 yrs old. After replacing/checking cables, the sound returned but black screen. Called Samsung. Nearest authorized dealer over an hour away. Googled the issue. Everything pointed to T-con board. I ordered this & replaced myself. Now I have 1/2 white screen, 1/2 yellow & red screen. Still no picture. Can't get menu to appear so can't factory reset. No buttons on back to reset manually. Now what? Anyone dealt with this?

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