Had an issue last year with a TCL 55S401 (discussed [post|828422|here|new_window=true]). Swapped boards and unit has been working fine since. Yesterday, not only has the original problem resurfaced, but with another issue not encountered before.
[image|3346482]
What's seen in image is what occasionally happened when doing a restart or reset from TV system menu. Lines thickness and colors varies with each re-occurrence. TV audio not affected. If left unplugged for a few hours, unit works until eventual failure.