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, the described symptom almost always point to an internal hardware issue or more particularly, possible suspects after a review of the Service Manual are:
All of the above would require that the unit be opened up for visual inspection, voltage/continuity/resistance checks, confirm faults and effect repairs.
I realize that the above information may perhaps be not what was expected. Unfortunately, there is no quick-n-easy fix and neither is there a workaround; sorry for having to be the bearer of bad news.
If comfortably able and feel safe to do so, 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?