TV screen is very dim after replacing new main board
So my aunts TV screen went out was the main board. So I replaced it and when I turn TV on your able too see the screen but it's very dim and when I adjust the brightness it doesn't seem to affect anything. I went thew some of these forms to diagnose the issue and found that possible the backlight board could be out what's the best way to troubleshoot this issue??
Its a RTU5540-B Rca