Vertical lines, kdl-40lx900, i susect tcon

[budwich]

Re: Vertical lines, kdl-40lx900, i susect tcon

ok... but at least now the forum knows its got four leads ...:-)

Of course... I am just going by your "comments on interest" around said component. My question its either some form of capacitor and/or resistance pack. The next thing to do would do some measurements around it to possibly confirm that... perhaps the results will shred some light on the numbers (hint... the readings might be those numbers in some form). Related to that, I am not sure its wise touching a "powered" board with your fingers on any conductive surfaces... they may be enough "energy" to hurt you and / or maybe be enough to hurt a given component depending on what the fingers "bridge". :-)

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

thanks for the reply. thats the thing, if you mean component "33300 K028F"
i can not measure the voltage, as soon as i try, the screen turns black, and when i take the dmm measurement lead away then it comes back but it looks different afterwards. when i turn the tv off and on again its same as always.

ok... but at least now the forum knows its got four leads ...:-)

Of course... I am just going by your "cooments on interest" around said component. My question its either some form of capacitor and/or resistance pack. The next thing to do would do some measurements around it to possibly confirm that... perhaps the results will shred some light on the numbers (hint... the readings might be those numbers in some form). Related to that, I am not sure its wise touching a "powered" board with your fingers on any conductive surfaces... they may be enough "energy" to hurt you and / or maybe be enough to hurt a given component depending on what the fingers "bridge". :-)

[budwich]

Re: Vertical lines, kdl-40lx900, i susect tcon

OK... but I didn't ask you to measure voltage.... you are trying to find out what that component might be. There are other types of measurements that will tell you something about the component.

further, have you tried operating the tv with one of the tcon cables disconnected, either far right or far left... what is the resulting picture. Further, if you access the edge boards on the bottom of the panel that the tcons are connected to, there are flex tab cables running from those boards to the panel. If you gently rub those flex tabs on the side associated with the disconnected tcon cable, are there changes in the picture / screen on that side?

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

thank you very much for the reply, please let me know what kind of measurements i should take, i have tried each of the 4 cables that go from the tcon to the panel as individually connected, when i do this i get washed out bright lines, without anything from the menu or channel visible.
i took the panel apart the other day and tried to apply pressure, to the bonds/flex cables individually, but there was no change what so ever. i will take it apart again one more time if necessary. it was very much a pain in the butt to take it apart.

thank you in advance

OK... but I didn't ask you to measure voltage.... you are trying to find out what that component might be. There are other types of measurements that will tell you something about the component.

further, have you tried operating the tv with one of the tcon cables disconnected, either far right or far left... what is the resulting picture. Further, if you access the edge boards on the bottom of the panel that the tcons are connected to, there are flex tab cables running from those boards to the panel. If you gently rub those flex tabs on the side associated with the disconnected tcon cable, are there changes in the picture / screen on that side?

[budwich]

Re: Vertical lines, kdl-40lx900, i susect tcon

Either I don't understand you or you don't understand me. Please ONLY DISCONNECT one of the four cables (either one at each side to the tcon card).... as opposed to only having ONE cable connect which is the way that I read your post. Please confirm / re-read the post.
Further on looking at the bottom flex tab cables, I know its a lot to get at them so don't try this again yet. Just do the "one cable disconnected" tests.

As for measurements, I just suggested that you do simple resistance measurements across the component in question... what do you get?

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

i just did what you asked, the far right one is disconnected and the other 3 flex connected gives me the same side blank white i.e. 1/4 of the panel, and the rest has same pattern pink/white vertical lines, and the other side around on the far left if i repeat the same, gives me the same, although one of the sides the left one i.e. CN1301 if i disconnect that then the picture next to it is a bit darker then the rest of it, but still same pattern.

also i did the resistance measurements, without power, i attached a picture, to show what gives what value. of what i measured.

thank you in very much in advance

Either I don't understand you or you don't understand me. Please ONLY DISCONNECT one of the four cables (either one at each side to the tcon card).... as opposed to only having ONE cable connect which is the way that I read your post. Please confirm / re-read the post.
Further on looking at the bottom flex tab cables, I know its a lot to get at them so don't try this again yet. Just do the "one cable disconnected" tests.

As for measurements, I just suggested that you do simple resistance measurements across the component in question... what do you get?

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

did same measurements with power on. i attached picture

[budwich]

Re: Vertical lines, kdl-40lx900, i susect tcon

ok... not sure what to say... what does "nothing" mean.... you should watch your terms closely. Nothing means "0". High resistance is something else... but certainly not "nothing".

Anyways, you make some interesting observations about the screen when you disconnect one cable depending on the side. Do you have a picture of this. Further are you able to feed a signal to the set? If so, are able to find any test dvd that you can get a well defined pattern displayed to help with evaluating the screen?
Sorry for all the questions but its hard to "see thru your eyes and hands" with the internet between us... :-) and lack of full schematics and design for the set.

Having said that "bit darker" doesn't sound good based on my very limited experience.

[freakaftr8]

Re: Vertical lines, kdl-40lx900, i susect tcon

The sounds about right. Your panel is ok. I am under the assumption that you have a bad processor or nvram on the tcon. You still have to look at this fact. Your 3.3v is jumping around. Should be steady. Something loads down the 3.3v feeding the nvram. Is one of those heating up and the other stays cool?

These in question are ic301 and ic303

[budwich]

Re: Vertical lines, kdl-40lx900, i susect tcon

OP... are you saying there is degree of "darkness" but its the same regardless of which cable I have disconnected or that one side is darker than the other? Pictures will help.
As freakaftr8 indicates, you still need to look at the varying 3.3v if that is the case.

there are "notes" in the service manual around the 3.3v "stuff" ... not sure why they are there... from the company, from someone troubleshooting and copied onto the "ripped copy of the manual"... ???? anyways, they appear to point to capacitance issues around the 3.3v regulator area... not sure I am reading things right. Anyways, if the 3.3 isn't stable, that is an issue.

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

thank you very much for the reply, both ic301 and ic303 have about the same temperature, none of them seems more warm then the other, but they are almost cool barely warm i attached a picture of the points where i did
those measurements, just in case so there wont be confusion, it is labeled CN101, so im not sure anymore if those are testing points

thank you in advance

The sounds about right. Your panel is ok. I am under the assumption that you have a bad processor or nvram on the tcon. You still have to look at this fact. Your 3.3v is jumping around. Should be steady. Something loads down the 3.3v feeding the nvram. Is one of those heating up and the other stays cool?

These in question are ic301 and ic303

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

thank you for the reply, i took today picture of the panel while the flex cables are disconnected, please see attached pictures

what i meant in post #47 is that when i measure the resistance where it says
34.7 Kohm that the display does not turn black and nothing happens, unlike the other side where i measured 40 KOhm it turns black and when i take the DMM probe away the display looks different, the colors have changed , but not better.


btw. which 3.3V notes are you referring to in the PDF? can you tell me what page you have seen those please?


thank you in advance

OP... are you saying there is degree of "darkness" but its the same regardless of which cable I have disconnected or that one side is darker than the other? Pictures will help.
As freakaftr8 indicates, you still need to look at the varying 3.3v if that is the case.

there are "notes" in the service manual around the 3.3v "stuff" ... not sure why they are there... from the company, from someone troubleshooting and copied onto the "ripped copy of the manual"... ???? anyways, they appear to point to capacitance issues around the 3.3v regulator area... not sure I am reading things right. Anyways, if the 3.3 isn't stable, that is an issue.

[freakaftr8]

Re: Vertical lines, kdl-40lx900, i susect tcon

Ok well considering the 4256bwp is the eeprom for the tcon and you have 3.3 volts jumping all over I would consider that either the eeprom is faulty, there is a problem with the receiving end of that voltage which is most likely the ram for the main processor, or you have a faulty voltage regulator for that output voltage. Tcon boards are very finicky when it comes to fluctuating voltages or low voltage on one of the rails

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

thanks for the reply


so, lets say the eeprom is faulty, do i need to program it? or would an off the shelf replacement work?
i have to check one more time the rest of the pins which are connected to the chip will do that in a few hrs i think

btw. those pins seem to connect to nowhere so i wonder even if its fluctuating the voltage if it matters? i will recheck my statement though

Ok well considering the 4256bwp is the eeprom for the tcon and you have 3.3 volts jumping all over I would consider that either the eeprom is faulty, there is a problem with the receiving end of that voltage which is most likely the ram for the main processor, or you have a faulty voltage regulator for that output voltage. Tcon boards are very finicky when it comes to fluctuating voltages or low voltage on one of the rails

[freakaftr8]

Re: Vertical lines, kdl-40lx900, i susect tcon

That's most likely a dual layer board. Most likely the traces are embedded in the middle of the board where you can't see. Unless there's a company out there like shop Jimmy that reprogrammed EEPROM you can't just buy a new chip and replace it it has to be programmed. If you don't have an EPROM reprogrammer there's not much to do except buy a new tcon

[budwich]

Re: Vertical lines, kdl-40lx900, i susect tcon

not sure which was being displayed on the screen for those pictures, but I don't think its good. The pictures are not the "same", right to left versus left to right. There appears to be some "horizontal marking" in one direction that is not there in the other. To me, that would indicate some form of issue with the panel on the horizontal which is not good.

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

thanks for the reply
so i checked the VCC on the EEPROM 4256BWP its a steady 3.3Volt, the 2 pins which have the voltage jumping up and down, one of them is SCL and the other is SDA i marked them in the picture which i attached, so i wonder can i go ahead and unsolder/lift both of those legs up and see if its the same on both sides? or will that cause some trouble? because i was thinking if i would do that and check the legs on the chip that would mean then its the chip, and if its not on the chip but still same thing happening on the board then the cause is somewhere else, who knows maybe even a regulator or something like that. maybe a wonky smd capacitor

thank you in advance

That's most likely a dual layer board. Most likely the traces are embedded in the middle of the board where you can't see. Unless there's a company out there like shop Jimmy that reprogrammed EEPROM you can't just buy a new chip and replace it it has to be programmed. If you don't have an EPROM reprogrammer there's not much to do except buy a new tcon

[Dogcatdog]

Re: Vertical lines, kdl-40lx900, i susect tcon

thanks for the reply,
that line comes and goes independent of temperature or anything else from the environment, also it does not matter if i let it run for good 30mins, its also there when all 4 flex cable/ribbons from the panel to the tcon are connected.
its really random, i tested it if i turn the tv on and off like 50 times it does not matter sometimes its there and sometimes not.
any thoughts?

not sure which was being displayed on the screen for those pictures, but I don't think its good. The pictures are not the "same", right to left versus left to right. There appears to be some "horizontal marking" in one direction that is not there in the other. To me, that would indicate some form of issue with the panel on the horizontal which is not good.

[budwich]

Re: Vertical lines, kdl-40lx900, i susect tcon

put an known input on the screen and look at the result when one cable is removed and then repeat from the other side. If the display has "artifacts" that are "suspicious", it will be obvious. There are all sorts of dvd (and others) with known test patterns (color bars for example) that will help.

As for the problem being there when all the cables are connected... yes that is likely and obvious. The issue is that you appear to get rid of it when you have one of the cables disconnected... that tells me you have an issue with that side.

[freakaftr8]

Re: Vertical lines, kdl-40lx900, i susect tcon

I don't know how to be sharp tcon board with handle this but I know that there is a procedure that involves shorting the SDA pin of the EEPROM to either VCC or ground to reset it on samsung boards. Look into EEPROM reset on the Internet and look at how the pinout configuration works. I guess at this stage you have nothing to lose