Chosen Solution
I have troubleshoot a backlight issue to it being identified as the left side backlight or the main board .i need to troubleshoot whether the issue is in the backlight or the power connection coming off the main board… i got to this point by removing the right side connection and leaving the left side. 5 to 10 min backlights went out. I performed the test on the right side by and backlights continue to stay on with no problems. So my problem is on the left side either with backlights or the connector powering the backlight off the main board. my next replacement will be the main board … unless I can test the back light strip on the left side … In the first image its the connection circled in black on the left that appears to be the issue.
UPDATE 03/08/20 here is my question … would one Bad LED cause BOTH left and right side backlights to go out after tv is powered on for approx 5 min. Keep in mind the left side and right side are using different connectors sources as you can see from the photo. On the mainboard pictured the right cable goes to the right backlight and the left cable goes to the left backlights. I will replace the bad connector strip either way. Thanks for pointing me to the backlights.
@flex4705 this sounds actually more like a backlight strip failure. I would suggest to get an inexpensive backlight tester first. Check the strips. It does not sound like a mainboard issue since the other side works. So either backlight strips or power board would be my focus.
