UN55B6000VF white screen with disconnected T-Con

[Pioneerx01]

I am looking at UN55B6000VF that has mostly white screen where 2/5 of it is slightly darker. When I play something on the TV, the 2/5 that is slightly darker has shadow of an image on it that is playing while rest is pure white.

See attached pictures (the horizontal lines are there only on camera). When I disconnect all T-Con ribbon cables, the screen is fully white no shadows.

If the entire screen would have shadow of the image playing, this could be gamma issue related to T-Con. (there is no AS15/19 I as far as I can see), however since only 2/5 of the screen is visible, I am worried this is more of an panel issue.

Thoughts?

T-Con in question (35-D043524): http://www.shopjimmy.com/cmo-35-d043524-t-con-board.htm

[CapLeaker]

Re: UN55B6000VF white screen with disconnected T-Con

Disconnect only one side of the T-con, look at the screen, then the other side of the T-con.

[Pioneerx01]

Re: UN55B6000VF white screen with disconnected T-Con

When I disconnect right ribbon cable only I get mostly white screen with some shadow portions and few white horizontal lines. When I disconnect left ribbon cable only I get pure white screen.

However, now when I disconnect both cables I get dark screen (as I would expect) with back-lights only.

[Pioneerx01]

Re: UN55B6000VF white screen with disconnected T-Con

Anyone has any ideas on this? Should just get another T-con and see what happens?

[hienton2]

Re: UN55B6000VF white screen with disconnected T-Con

Check sub voltage supplies on tcon

[Hamie]

Re: UN55B6000VF white screen with disconnected T-Con

Check voltages test points on the t-con.
Avdd
Voffe
Vone
Vgl
Vgh

[budwich]

Re: UN55B6000VF white screen with disconnected T-Con

When I disconnect right ribbon cable only I get mostly white screen with some shadow portions and few white horizontal lines. When I disconnect left ribbon cable only I get pure white screen.

However, now when I disconnect both cables I get dark screen (as I would expect) with back-lights only.

those lower lines when the side is disconnected is likely not good. As you have seen, when a "good disconnect" happens, the screen goes white on the disconnect side.

I would check / reseat cabling in and around the panel edges where possible and see if things change.... but would suppect a panel issue on the side when disconnected shows horizontal lines.

[Pioneerx01]

Re: UN55B6000VF white screen with disconnected T-Con

Sorry, for delayed response. I had to go out of town for few days.

When I can back to this TV I have noticed that there is awful lot of water residue on the screen itself, from wet rags. If previous owners used this "cleaning" method since day one, yep you guessed it, corroded contacts on driver boards. See attached pictures. I so wanted this to be a T-Con board fault and, but logically I knew it was most likely panel. Oh well.

Thanks for your help guys.

[ReeceyBurger123]

Re: UN55B6000VF white screen with disconnected T-Con

Clean the area well with ipa and reflow smd parts. This is the reason why I NEVER buy Led Tvs with Lcd faults only backlight or power/firmware failures.

[Pioneerx01]

Re: UN55B6000VF white screen with disconnected T-Con

I am working on cleaning the contacts, but no luck so far. I have even found compatible replacement ribbon cable. There is corrosion inside of the latches that connect the ribbon cables that I can't get out. Even if I do, I am not sure how will I address the corrosion on the tab bonds.

As to the reflow, how would one go about doing that on driver board, without damaging the this tab bonds and their ribbon cables or panel? Should I just manually re solder every contact on SMDs?

[lin4sm]

Re: UN55B6000VF white screen with disconnected T-Con

Most probably you will need to replace some of the SMD caps as from photos I can see that they are damaged by corrosion. Ribbon cable that connects board to screen will have to be cut slightly (just not too much) approximately 1 mm. All traces have to be connected back together where corroded. Tiny wire can help connecting them. SMD components that are not damaged should be reflown I do this this with solder iron and a lot of flux. It is job that requires precision and skills, possible to repair. Had tree TVs like that 2 managed to repair. Coca cola is worst thing One of the TVs had something like coca cola spilled on screen. Everything sticky too many contacts burnt.