Bad capacitors - Samsung LCD TVs
Ron Czapala
Posts: 2,418
Certain models of Samsung LCD TVs have problems caused by defective capacitors which expand and swell.
My three year old 40 inch Model LN-T4065 set would show pink/purple spots when it was first turned on. Turning it off, waiting awhile and turning it back on usualy fixed the problem - until the next time.
Other people have had it progress to the point where it takes minutes for the picture to appear or not appear at all!
I found a forum where 23 pages of threads discuss the problem and solution. I replaced four 1000 uf capacitors and the problem is resolved.
The origianal ones were 10v and the new ones are 35v - a little bigger in diameter but just fit.
Also, I used 85 degree centigrade rated caps since they were available at Radio Shack, but the original ones were rated 105 degrees. I intend to buy some 105's just in case.
The forum discussion is found at: TechReport.com
My three year old 40 inch Model LN-T4065 set would show pink/purple spots when it was first turned on. Turning it off, waiting awhile and turning it back on usualy fixed the problem - until the next time.
Other people have had it progress to the point where it takes minutes for the picture to appear or not appear at all!
I found a forum where 23 pages of threads discuss the problem and solution. I replaced four 1000 uf capacitors and the problem is resolved.
The origianal ones were 10v and the new ones are 35v - a little bigger in diameter but just fit.
Also, I used 85 degree centigrade rated caps since they were available at Radio Shack, but the original ones were rated 105 degrees. I intend to buy some 105's just in case.
The forum discussion is found at: TechReport.com
Comments
Caps - especially large power supply caps - remain one of the weakest links in modern electronics as the electrolytic chemicals are not very stable and eventually fail. It is far better to replace them early, before failure is drastic. Caps are easy to replace, chips are nearly impossible to do so.
Another big factor with monitors and TV displays is dust. I have a Lemel monitor that goes haywire when enough dust accumulates on the circuit board. So far I've cleaned it 3 times over several years and it continues to provide good service for a year or so before the dust creeps in and it requires another cleaning.
The hardest part of these kinds of service is opening the case for the first time. Fortunately, a lot of people are willing to contribute DIY videos on Youtube.
But whatever you do, you really have to think through what people are telling you as many don't fully know how to handle the technical details of today's electronics. Generally, I research and compare for a few weeks before thinking over the suggestions, then make my own plan of action.
I had to replace two caps in it
Here is the link to it where I had just repaired it It still working
http://forums.parallax.com/showthread.php?t=126614
I have had today three Computer Power Supply fail because of bad Caps
Online I found it was one of several known issues related to various capacitor failures. Upon contacting Samsung tech support, I learned that since my TV is "small" (only 26-inch) I'd have to mail it to them for repair.
Eh. I hadn't saved the box.
Instead, Andy opened it up, found the bulging cap, and replaced it with a 16 V, 3300 µF cap from his What's a Micrcontroller kit.
-Steph Lindsay