Need Assistance Troubleshooting a Samsung LCD TV

I have a Samsung 40" LCD TV LN40B530P7N that has ghosting, other wise this is a great working tv that I would like to repair myself if possible.

In the past I have replaced blown caps in other lcd tv's and was able to make a good repair. For additional background I am a retired US Marine who was an Avionics Tech on helos, and I hold an Extra Class License (ke4ilg) so I believe I can do the repairs but can't decide what is the proper direction to go.

Ok so here's what I have done so far: I watched a lot of youtube videos and followed repair tips to no avail. One I followed was removing and re-inserting the ribbon cables from the T-Con board to screen input. This did not help.

Next I tried the internal self test on the tv's menu. This test displayed a color bar test and it was great with no ghosting at all. The self test stated that if the color bar was good then the problem is from the inputs to the the tv, ie cable box, dvd player etc.

So since I know the Directv box is working correctly I changed the input from HDMI cable to the component cables, RCA jack cables ,yellow, red and white. All the same results.

The main board has all the inputs including, AC power, cable input, HDMI input and component input RCA jack.

So I believe its either the main board or the the T-Con board. The used price on each of these boards about $100 for one and about $55 for the other. I don't want to buy the wrong one.

Anyone who feel qualified please let me know your thoughts and those who don't think you are qualified are also welcome to comment. Thanks in advance for your support. Mike

Mike, did you check out any potential troubleshooting on the BadCap site??

I am in no way a TV repairman , so my advice would be to replace the cheapest one first . That's always my mentality when doing automotive repair . I have a friend who repairs tvs and I can give you his number if you shoot me a pm . After reading the end of your post if the main board has all the inputs that's prob the cause . but this is not my forte .

Quote:

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Originally Posted by Mechanic688

Mike, did you check out any potential troubleshooting on the BadCap site??

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I have checked there and other sites. So far none have come close to my situation which is different because of the troubleshooting I have done so far.

I am asking on our forum because I have a lot of confidence in our members respond to the best of their ability. And if this doesn't work I will put together a question for the Badcap forum. Mike

Just for giggles you try and degass it? I picked up a computer monitor not that long ago that the person tossed because they couldn't get the picture fixed. I degassed it an its worked like new ever since. You said you tried a composite cable. Ever try a different set of HDMI/Composite cables? My brother-in-law picked up this usb capture card and we discovered the composite cable was broken in the middle(didn't find it until we unhooked it to find it was super soft in the middle). Just my two cents.

Before you replace any boards, on some of the newer LCD TVs the Digital NR (Noise Reduction) function can cause ghosting or signal problems in general. You could try adjusting that and see if it helps. Also make sure your resolution is set to "Optimum" if you have that option. I think this is the right info for your model:

Adjusting The Digital Noise Reduction (DNR) Feature

I can only suggest some tried and proven trouble shooting advice. 1. rethink when did the ghosting problem start (if you know that)? Then think what event was done just before that? Was a change made? Input cables, and/or was another device added inline or parallel to the LCD, cable box or signal splitter? 2. When trouble shooting any electronics device, the fastest method is isolate to circuitry that can cause the problem, by first eliminating what cannot. 3. Cut the circuitry that can cause this type of problem in half, by tracing back into circuitry, verifying what's OK and what's not. If all check good, from a mid point, that's good, you now go back and work forward with same step by step process, (I know as a marine avionics tech. you know this, just reminding what we were taught!). 4. Ghosting is almost always a feedback problem, impedance matching, bad RF shielding, isolation caps on AC input circuit, and don't forget about other equipment in proximity to and/or on same AC power source.

Maybe not much help, just a reminder of the basic 1, 2, and 3's of trouble shooting.

Thanks for all the responses.

The tv was in this condition when I got it.

I've only heard of degassing CRT type tv's so that would be new to me for LCD tv's.

The step by step troubleshooting is something I can do but what seems to be next is getting voltage reading from surface mount devices. Since I don't have the voltage readings I should get I am going to hold off on that.

Here's the where I am now: I have ghosting from a known good source with known good cables and the self test color bar has no ghosting.

Again thanks for the responses. Mike

Can you menu access the control unit? Set on/off functions of the video card unit? Set filtering tools/functions (deblocking/N.R. Noise reduction)? Maybe unit has been defaulted to initial settings? Is there a setup procedure? The video card unit will do a lot of programing functions like signal coupling, restoration circuitry you may need to set some of these functions.

I have tried some of that and I am going to give it another go tomorrow, Sunday. An earlier post gave me a link to the directions.

Also one of the members got me in contact with an experienced tv repairman willing to advise me. So I have high hopes and will keep you the forum members up to date with my progress. Mike

That's good and hope between the two of you can solve the issue. I was going to say that degassing crts is reset or refresh on lcds. Still sounds like one of the holds may be off or bad. Also now that I'm thinking about it, is the ghosting live or static because if it's static it's the screen itself due to burn-in. It's hard to troubleshoot when it's not infront of me.

I was able to get a telephone consult for troubleshooting my tv with an experienced tv repairman. I found it helpful and will be trying out the advise given. If/when I determine what the end outcome I will share with the forum. Mike

Quote:

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Originally Posted by miked

I have a Samsung 40" LCD TV LN40B530P7N that has ghosting, other wise this is a great working tv that I would like to repair myself if possible.

In the past I have replaced blown caps in other lcd tv's and was able to make a good repair. For additional background I am a retired US Marine who was an Avionics Tech on helos, and I hold an Extra Class License (ke4ilg) so I believe I can do the repairs but can't decide what is the proper direction to go.

Ok so here's what I have done so far: I watched a lot of youtube videos and followed repair tips to no avail. One I followed was removing and re-inserting the ribbon cables from the T-Con board to screen input. This did not help.

Next I tried the internal self test on the tv's menu. This test displayed a color bar test and it was great with no ghosting at all. The self test stated that if the color bar was good then the problem is from the inputs to the the tv, ie cable box, dvd player etc.

So since I know the Directv box is working correctly I changed the input from HDMI cable to the component cables, RCA jack cables ,yellow, red and white. All the same results.

The main board has all the inputs including, AC power, cable input, HDMI input and component input RCA jack.

So I believe its either the main board or the the T-Con board. The used price on each of these boards about $100 for one and about $55 for the other. I don't want to buy the wrong one.

Anyone who feel qualified please let me know your thoughts and those who don't think you are qualified are also welcome to comment. Thanks in advance for your support. Mike

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I want tocomplete this thread with the outcome. Short answer the tv will not be repaired.

A member supplied me with the contact information of a TV technician who did a telephone troubleshoot consult. (Bet you never expected to read something like that) The consult went well. I did the couple of actions suggested by the tech with no good effect and then purchased a replacement T-con board.

Once I installed the new T-con I got different results but the tv was not fixed. There is a bit more to it than I stated but not at all interesting.

The consult was very reasonable and confirmed my troubleshooting of the problem and confirmed what I thought was the likely problem.

The T-con board cost me about $49.00 the other likely board would cost a little over $100. Replacing that board is no guarantee that the tv would work since the bad board might have damaged both of the T-con boards.

I have chosen to cut my losses and move onto other projects. I have been successful in repairing two other LCD TV's in the past, in one I replaced capacitors and the other reinstalled the same ribbon wires on the T-con board.

I wish I have more wisdom to share but I did want to close this thread. Best to all and thanks to those who contributed. Mike

the sad part is that the COST of LCD/LED tv's has gone down SO much in the past year, it is almost not even worth the time and effort to fix them if under 42". The parts being $30-40 and then the time...plus you STILL never know if that is the fix or not.

When in doubt, sell it off as a parts tv to someone local and just get another...again sad but true.

Thanks for the info.........I'm the same way........I usually cut my losses on any of this crap before dumping a ton of money into anything electronic

I was suggested the BADCAPS site too by a SMF member. And Thank You very much to the SMF member too, Its a fantastic site, just like SMF is.

I do not remember what my flatscreens model was but.. It was ghosting too.
It did change its ghosting as the TV warmed up. Turns out they have a bad connection from the mylar ribbon to the glass screen (LED).
As the screen warms up it expands and the contact changes and the screen changes, but its still ghosting.

The answer was.... wait for it. Put a strip of foam door seal, with the sticky back to it, across the mylar where it contacts the screen.
This pushes the mylar onto the screen harder, fixing the problem.

I found that if I squeezed the top right edge of the screen the ghosting sorta fixed itself a bit.
Because theres metal arouynd the mylar contact area it cannot be squeezed by hand enough to fix it, but its easy to see that it makes a difference. And that its probably the contacts there that are causing the problem.

BADCAPS'COM has really set itself up to help the 'average joe' out as well as the proffesional. And as a great way to make some extra money for a lot of people in these hard times (for some) Just like SMF has.
In these times of dog eat dog, its really nice to find people are helping out each other. /kiwi

I checked what flatscreen I had and it was a Samsung. With any luck its got the same problem as yours.
So it could be a 'Zero $ fix'.

Mines a Samsung model LA46N81B
Model code LA46N81BX/RAD
Type TU46SO

There will be differences between our flatscreens. We use 240 AC @ 50hz
and I think theres a different amount of lines in the picture too.
There could be a difference in the way the TV picks up recption, ie mines probably set up to pick up the signal from a ordanary ariel rather than a digital sat dish.

So, the actual design of the screen and connections might be the same. Even if theres a different size screen.

So, start the TV up and grasp the top right corner about two hand widths in from the end of the screen and squeeze firmly but not too much or the screen may crack.
If this helps its a hour and a bit to fix it using foam door seal tape.

eesakiwi, if the issue is "ghosting" then before trying the "tape" fix try this. Remove the ribbon wire from the the T-con connectors and re-install them. It's the same as the tape procedure in the youtube video but no tape. This is the way I repaired one of the tv's I used in one of the tv's I use in my house.

Warning you need to be very gentle doing this type of repair as you can ruin the tv you are attempting to repair. I tend to view youtube videos before doing this type of work to walk me through what i'm going to do. Good luck, Mike

Miked, yup, I did that to check if that was what it was before finding out about badcaps.com.
I was really suprised to see the whole half side of the screen to go blank once I had removed the single strip of mylar completely. It did shift around as I moved it.

Earlyer I had squeezed the top right hand of the screen and did notice the difference. But that was not enough to fix it so I decided that was not all of the problem. I think this strip is just pushed against the back of the glass sceen now.
Up till finding about badcaps I figured it was glued onto the screen like normal and if it had come unstuck from the screen there would be no way to 'reglue' it back on. (previous experience with calculator screens)

oh, logansyrc may have ment 'degaussing' rather than 'degassing' earlyer on.
I use a 7inch tablet too.......