Samsung LN40A500T1F intermittent distortion

[Burl]

I have a Samsung LN40A500T1F. Most of the time when I turn it on after it has been off for a while, I get audio but the picture has lines and colors that change and the intended image is not displayed. Sometimes, I can leave the TV on for about 1 minute, turn it off, then turn it back on and get a good viewable image. If I leave it on, the good image remains viewable until the next time it is turned off, cools down and is turned back on. I have attached some pictures, the first three of which were taken within about 10 seconds of each other. The fourth picture was taken after I turned off the power and then turned the TV back on. Does this sound and look like a T-Con problem?

Thanks for any help you can provide.

[CapLeaker]

Re: Samsung LN40A500T1F intermittent distortion

clean and reseat the ribbon cable from the main to the tcon and from the tcon to the panel. Also check the tab bonds.

[ReeceyBurger123]

Re: Samsung LN40A500T1F intermittent distortion

clean and reseat the ribbon cable from the main to the tcon and from the tcon to the panel. Also check the tab bonds.

+1

[Burl]

Re: Samsung LN40A500T1F intermittent distortion

Update: I thought I'd give an update for others who might have a similar problem. Although I had disconnected and reseated the cable ends that connect the main board to the T-con board several times before posting, it never seemed to fix the issue I was having and wiggling the connectors while the picture was distorted never corrected the problem. So, almost a week ago now I removed the cable connectors and used some compressed air to blow off the male and female connections. Then I used a Q tip and some isopropyl alcohol to clean both the male and female connectors at each end of the cable. When I reconnected the cable and turned the TV on it worked well with no distortion. The next morning, when the TV was turned on the distortion appeared. I turned the power off and back on and the distortion disappeared. We have thermal cycled the TV 2 or 3 times a day since that time and have not gotten distortion a single time. So, while it is still too early to tell whether the problem is resolved, I do believe CapLeaker and Reeceyburger123 pointed me in the right direction. If the problem starts reappearing, I plan to do some more aggressive cleaning of the cable ends and receptacles. I will report back a time or two to this thread to update the status of the problem as time goes on. In the meantime I am keeping my fingers crossed. Thanks CapLeaker and Reeceyburger 123 for your help!

[maxvalutech]

Re: Samsung LN40A500T1F intermittent distortion

Tape the connector cable from main to tcon very securely to the panel rear at each end and this may avoid later problems

[Burl]

Re: Samsung LN40A500T1F intermittent distortion

I thought I would give an update. What I eventually found was that the cable that attaches to the video board needed to be pulled away from the panel. Attached is a picture of a pill bottle I taped in place to keep the cable pulled away. I had previously tried cleaning the cable ends and the connectors, first with isopropyl alcohol and later with some very light sanding with find sandpaper followed by more isopropyl alcohol. These things sometimes temporarily fixed the problem but within a week or so the problem was back. I also placed spacers such as paper on the back side of the connector that attaches to the video board to help force the metal elements of the connector to the receptor but that did not work. I tried taping the cable to the panel on both ends of the cable just before the connector but that seemed to make things worse. I also purchased a cable off of E-bay but it did not perform any better either. As I mentioned earlier, the latest thing I have tried is to ensure the cable is pulled a certain amount away from the panel when the TV is powered on. This has been working reliably with repeated power-ons and offs. Attached is a photo of a pill bottle that I have taped to the panel which creates this "right" amount of pressure pushing the cable away from the video board. If the pill bottle is placed closer to the video board the pressure is apparently too much and if the pill bottle is placed too far away from the video board the pressure is not enough to reliably get an undistorted picture. The location as shown in the picture is "just right" for my TV's problem.

What has been difficult is that once a good picture was obtained over the past months, no amount of wiggling or moving cables or cable connectors would cause the picture to get distorted, which has made it harder to troubleshoot. I do thank those of you who directed me to the cable connector with the suggestions of cleaning, taping, etc. Without that direction, I am not sure I would have realized it was simply a connection issue. I probably would have assumed one of the boards was bad and would have spent money that probably would have been wasted.

Thanks again to those who provided suggestions that got me headed in the right direction.