Facing TV Problems? Ask a TV Technician.
Hi and welcome to JustAnswer,Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially, with the description of "... tv goes blank...", is there still sound?
Would the blank screen be all blue, black or white?
Yes please; test the sound if still present even with a black screen.
Consider an experiment (if have not been done).
Power on the TV and set to a program/channel. If at all possible, darken the room where the TV is. Wait for about 5 minutes or more. Shine a flashlight at an angle (not directly) and nearly but not touching the screen where the volume level / menu display is usually seen.
Press the VOL UP/DOWN or MENU button and note if a dark/ghostly image of the volume level or MENU could be seen.
Post back results. The above is a test to determine if it is a backlighting issue.
Further checks then would be on the inside circuitry if comfortably able.
Are you then considering a DIY (do-it-yourself) repair approach? If yes, do you have access to and familiar with a multi-meter and even perhaps a soldering iron?
...sorry but DIY?
Great on the DIY.
Proposed preliminary tries (if have not been done):
Please post back results / observations of the above once done.
Additionally, post back too with clear pictures. Click HERE. This would enable common reference for further diagnosis.
A friendly reminder: voltage measurements and working on the inside circuitry would require that the TV be plugged in and turned on; it is therefore LIVE! Please exercise due care and caution.
Please post back how things turned up and/or should additional information be needed.