I was given an old 2004 model year 20 inch Sony TFT LCD monitor because it was dead. I tested it first and power supply seemed ok powered up no menus or self test. Pull it apart determine it is probably a issue with the LCD part of the display. Found a few of the plastic ribbon cables that connect the LCD to the control board for it. I used the side of my solder iron to heat it up to re-melt the solder. I did this to all of them to makes sure they were all ok. It now works ok for about 10 seconds with image then it randomly makes horizontal or vertical bars of different colors then occasionally going dark. When I shut it off and use the hard power switch and discharge the power then turn back on it does the same thing again. While working on it I saw no bad caps or other obvious issues on either board. The logic board has a removable chip with a sticker on it I believe to be firmware. I pulled this chip and reseated it.
I am kind of stumped now on what to do next. It is starting to look like a logic or capacitor problem now. But I want to lean toward logic because the caps all looked ok. Could be that I didn’t get the cables on correctly but it displays ok for a bit so I wouldn’t think that’s the problem.
Any suggestions on what else to look at or try appreciated. I’d like to fix it possible but if it involves new parts it probably be as cheap to just get a new one.
Thanks

 

Can u make sure the temperature of the IC's are OK. See whether u can keep ur finger on them

 

ok this was bad ribbon wires. dicided to just junk it. removed the lcd turned it into a lamp for looking at PCBs and task lighting.