It's an oldie, but I didn't find this problem in a search of the forum...
The symptoms:
TV randomly turns on and works normally.. After a few mintues, loud audio distortion and screen goes all blue (backlight stays on).
Will not respond to any buttons or remote controls, must unlplug from power.
Other times will just power on with no backlight and no control functions.
What I found:
When TV was not working normally, on main board (3647-0012-0150 (5B)), U4 (IRU1117-33) was only putting out 1.9V instead of normal 3.3V.
Replaced U4 (Fixed 3.3V AMC 1117) from a scrap board and all is good..
The symptoms:
TV randomly turns on and works normally.. After a few mintues, loud audio distortion and screen goes all blue (backlight stays on).
Will not respond to any buttons or remote controls, must unlplug from power.
Other times will just power on with no backlight and no control functions.
What I found:
When TV was not working normally, on main board (3647-0012-0150 (5B)), U4 (IRU1117-33) was only putting out 1.9V instead of normal 3.3V.
Replaced U4 (Fixed 3.3V AMC 1117) from a scrap board and all is good..