Sony Bravia KDL-52NX800 Black Screen and No Sound but Powers Up; Lines

I have an old Sony KDL-52NX800 Bravia LED TV. It suddenly will not display anything and has no sound. Tried unplugging/plugging the power cord. I hear a click and see the red standby LED light turn on. When Power button pressed (on remote or side of TV), the green LED lights up, but still no picture and sound. I tried hard reset (pressing Power button and Volume down button while plugging the power cord) but nothing happens. Contacted Sony and tried their other reset procedures but still nothing happens, same black screen. I hooked up the TV to my MacBook Pro via HDMI and my computer recognized the Sony as a second display. Still no picture or sound. I pressed Input multiple times to see if TV gets a signal from HDMI port, but nothing. I opened up the TV and took some pictures. Any suggestions?

I tested the power board pins at connector CN6150 and saw only standby power at 3.3v. No other pins had power. So, I reinstalled the connector with the TV plugged in and all of a sudden the TV came back to life. Now, I noticed the screen has a large number of horizontally and evenly spaced black lines. Lines appear on both menu and all input screens.

I removed the 4 ribbons from the T-Con board, cleaned, and reset the ribbons on the T-Con board. Also, I removed the LVDS connector, cleaned and connected it to the T-Con board.

Powered up the TV and I still have the lines on the screen. Nothing changed.

What do you think t problem is? Is the T-Con board bad? Ribbon cables? LCD panel bad? Not sure how to further diagnose the issue.