All the forums I know of don't have TV repair techs answering. It's been over a decade and not once did a tech tell anyone to replace Q25 or a specific part and then warrant the advice.

This failure on the web has been traced to panel (expensive), boards or cables. The TV techs use their experience to guide what part to replace first. Since they work in a repair shop or depot they have the luxury of a parts department or getting more than one head to weigh in.

Any tech I know does not diagnose from a picture and never works on their own.

That said, how big is this TV?
What model number?

Just last month I bought a 50 inch smart TV and it was on my porch for under 350 bucks. I found another for under 240 bucks. Repair is often not an option today.