Vertical lines, kdl-40lx900, i susect tcon

[Dogcatdog]

i suspect it is the t-con since it has vertical purple and white lines and a bit of grain.sometimes it gets worse sometimes a bit better, but the lines are always there, i might be something else, im not sure, i cleaned all the contacts with alcohol of the flex cable and the (LVDS cable on both sides) that is connected to the tcon to see if that fixes it, it did not change, it was still the same.
the kdl-40lx900 has the same tcon as the kdl-52lx900
no blinking no error code it just works, but the picture is as said with vertical liknes over the whole display in even spaces, sometimes a bit of green gets to the vertical purple/white lines
the tcon is CPWBX4351TPZF, oddly enough its a Sharp RUNTK4351TPZF

i would like to identify what is defect and repair the Tcon board since replacing it is not an option for me.
thank you very much in advance

[ReeceyBurger123]

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

Pictures of the fault please.

[mistertv]

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

have you checked the flat heat-sealed under the metal frame of the display?

[Dogcatdog]

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

here a picture of the fault,


and another one of the backside of the tcon, i found some test points and in 2 of those there is a voltage jump from 2.xxV to 3.xxV not sure if that is normal, but i think its not, both of those test points lead on the backside of the board connected to a 8 pin chip with markings "4256bwp ST k008h" i wonder if that is the culprit, i know that tcons are in generally fixable as long as one can find out what the problem is, like for example some sony have a as15-f chip that needs replacing and that fixes it, this tcon does not have that chip on board so i wonder what the problem is, it could also be something else.

thank you very much in advance

Pictures of the fault please.

[ReeceyBurger123]

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

That isnt an As15 or gamma Ic fault. I would say mainboard tbh.

[Dogcatdog]

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

mainboard huh? so how to test it? is there a way of testing that? there are not much components on the mainboard,actualy less then on the tcon i guess it cant be that hard to find. thank you in advance.

That isnt an As15 or gamma Ic fault. I would say mainboard tbh.

[ReeceyBurger123]

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

Is there anyway to bring the menu up, if so is it distorted ?

[Dogcatdog]

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

yes the menu is distorted and unreadable

Is there anyway to bring the menu up, if so is it distorted ?

[mattstolte]

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

.

[Dogcatdog]

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

btw. i found the service manual, its the same as kdl-52lx900 and others of the AZ1-H chassis i.e KDL-40/52/60LX900,903,904,905

here attached as PDF

[vinceroger69]

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

this maybe worth a read
http://electronicshelponline.blogspo...board-how.html

[freakaftr8]

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

That does look like a 3.3 volt RAMDAC problem on the tcon board and since you mentioned the 3.3 Volt is jumping all around I would suspect a problem there.

You can try applying heat to the cheek on board to see if the problem disappears but I don't think it's going to it looks like a shorted RAM module

[ReeceyBurger123]

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

that does look like a 3.3 volt ramdac problem on the tcon board and since you mentioned the 3.3 volt is jumping all around i would suspect a problem there.

You can try applying heat to the cheek on board to see if the problem disappears but i don't think it's going to it looks like a shorted ram module

+1

[freakaftr8]

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

Tcon not check on.. stupid cellphone with predicted text... lol

[Dogcatdog]

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

thx i gave it a read, i have tried to warm up the tcon with a hairdryer for a few mins to see if there is any change,and same with the mainboard, there was no change, have not tried it with freezing it yet.

this maybe worth a read
http://electronicshelponline.blogspo...board-how.html

[Dogcatdog]

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

i tried what you have suggested to apply heat to the tcon board, but im not 100% sure to which component i should do it so i did it over the whole board with a hairdryer for about 5 mins. there was no change, did same with the mainboard same result. i wonder if i should do the freeze thing with an aircan and see if there is any difference? or should i rather not do that, since some ppl say its not good to do, some say you can do it, its fine.

thank you very much in advance

That does look like a 3.3 volt RAMDAC problem on the tcon board and since you mentioned the 3.3 Volt is jumping all around I would suspect a problem there.

You can try applying heat to the cheek on board to see if the problem disappears but I don't think it's going to it looks like a shorted RAM module

[freakaftr8]

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

Can you post a picture of the front of the tcon board?

[Dogcatdog]

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

i hope those are good enough, i could not upload on the forum the files were to big or something is wrong with the forum it did not work i got error, so i uploaded here > https://mega.nz/#F!jRhzHI7Z!grnpZ9eeuAEWH4KV8Blr9g

Can you post a picture of the front of the tcon board?

[Dogcatdog]

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

i have also found this picture, it is the same tcon board CPWBX 4351TP ZF or CPWBX4351TPZF made by Sharp, the picture is in really good quality it makes it easier to see

[freakaftr8]

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

Ok apply some heat to ic303 and ic300 then test.