@bx2sms a failed backlight strip can cause this. You've already changed the board and still have the same symptoms because it originates from the strips. Replacing those will fix this issue.
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@bx2sms a failed backlight strip can cause this. You've already changed all the boards. your TV still has the same symptoms because the error originates from the strips. Replacing those will fix this issue.
@bx2sms a failed backlight strip can cause this. You've already changed the board and still have the same symptoms because it originates from the strips. Replacing those will fix this issue.