T-Con Problem but No T-Con Board? Sony 40CX520

[max1636]

I've got a Sony 40CX520 with a typical T-Con looking problem. The screen is blue all over and the image ghosts at times on the screen as seen here:

http://i1208.photobucket.com/albums/...psc80d5de0.jpg

So it's a T-Con like problem but the TV has no T-Con board as such. I don't understand why but there are boards for the same model listed on eBay here:

http://www.ebay.com.au/itm/LVDS-T-CO...386fc0b&_uhb=1

The connector from the main board goes straight to the board that goes to the ribbons that go to the panel itself. This is that board:

http://i1208.photobucket.com/albums/...ps9509e788.jpg

http://i1208.photobucket.com/albums/...ps1b4569b8.jpg

So should I replace the main board? Or is the set not worth fixing and maybe the T-Con's job is being done by the board connected directly to the panel?

[tom66]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

It's not a t-con issue. I've seen this on TVs with and without a t-con. It's a panel issue. Not repairable as far as I know. Yes the t-con is now on that unreplaceable panel board.

[max1636]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

It's not a t-con issue. I've seen this on TVs with and without a t-con. It's a panel issue. Not repairable as far as I know. Yes the t-con is now on that unreplaceable panel board.

That sucks oh well thanks then.

[tom66]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

There is a theory I have but I'm not confident on it, involving the VOFFE or VONE voltage on that panel board going missing. If you can see the test point for that you could see if they measure too low, too high or OK.

VOFFE: -5 to -8V
VONE: +20V to +30V

[max1636]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

There is a theory I have but I'm not confident on it, involving the VOFFE or VONE voltage on that panel board going missing. If you can see the test point for that you could see if they measure too low, too high or OK.

VOFFE: -5 to -8V
VONE: +20V to +30V

I just realized I forgot to mention. A few times the TV switched off then came back on by itself. But I thought maybe I was shorting the main chip when I was spraying it with freeze spray. Or is freeze spray non-conductive?

[max1636]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

I've actually just put the set back together because I thought it was done for. I will open it back up tomorrow and see what I can find.

[Th3_uN1Qu3]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

Freeze spray isn't conductive.

[tom66]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

Canned air "freeze spray", on the other hand, very much is...

[max1636]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

Freeze spray isn't conductive.

I bet it sounded like a dumb question didn't it haha well for some reason every now and then the set would turn off then back on by itself. Could it actually be because the chip was so cold the TV tripped out? Like an underheat if such a thing exists.

[ElBeat]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

Hello Members
I have the same problem with TV as max1636. I have not been treated with a freezing spray, so I think that is the reason TV does not restart itself. I've been measured VONE (28.2V) and VOFFE (-11.0V). I've been Googled around for this problem, red a thousand posts and this is the first one I've encountered for this problem. I'm really interested to hear the rest of your theory for these voltages. The TV is spilled all over the kitchen table and The-Wife-That-Must-Not-Be-Named have blessed me to do what ever it takes to fix it. I've the skills and patience but need the guidelines.

[tom66]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

Since VONE and VOFFE are good (new panel VOFFE seems to be higher, this is OK) I would suggest that it would be something wrong with the actual panel drivers or panel itself; sadly, not fixable in either case. Wish I had better news.

[ElBeat]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

The panel is one month old after a two year warranty. I believe this is a problem with some kind of color driver because I've been missing blue color, Max1636-red one."Missing" is a not accurate..may be slow response (minutes instead of ms ).

[tom66]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

Contact Sony - they've been sometimes willing to deal with customers a few months outside of warranty as a good will gesture.

[ElBeat]

Re: T-Con Problem but No T-Con Board? Sony 40CX520

I spoke with a technician from the official Sony service and told me they put pads under the ribbon cable (but this is not a fix).
I try myself to find a solution because I have knowledge and experience in electronics but not with TVs. I do not find any components that look as drivers for various colors. I wonder if there is any block diagram or schematic how to manage the LCD screen or on a T-con board