Sony KDL-46W5500 got backlights, no picture.

[Th3_uN1Qu3]

Have this TV which turns the backlights on but shows no picture. Have quickly checked voltages, may have missed some on the power supply and main but overall it looks ok. Responds to buttons, backlight brightness changes if i press the "Home" button.

Tcon fuse is good. Tcon is generating all drive voltages for the panel. Scoped some of the LVDS pins on the Tcon side, it looks to me like it's getting data from the mainboard.

Reflowed both BGAs on the Tcon, although the board underside did not show any signs of them getting hot. No change.

Would this pretty much guarantee the Tcon is bad, or should i dig deeper into the mainboard as well?

[attainteddragon]

Re: Sony KDL-46W5500 got backlights, no picture.

disconnect one half of the t-con, where it attaches to the panel and see if you get half a pic and then try the opposing half.

[vinceroger69]

Re: Sony KDL-46W5500 got backlights, no picture.

Edit! was typing this when above poster did too

do you get anyting on the screen if you remove one of the ribbon cables on the the tcon try doing this too the left and right ribbon cables.

[Th3_uN1Qu3]

Re: Sony KDL-46W5500 got backlights, no picture.

No picture with either half.

[dick_barton]

Re: Sony KDL-46W5500 got backlights, no picture.

Check very carefully to see if there is a small crack in the panel, perhaps in one of the corners.

[dskall]

Re: Sony KDL-46W5500 got backlights, no picture.

Are you getting data coming out of t-con

[Th3_uN1Qu3]

Re: Sony KDL-46W5500 got backlights, no picture.

To my uneducated eye, i would say "not really", hence why i suspect one of the processors on the T-Con to be faulty, as there is definitely data going IN via the LVDS cable. If you could show an example waveform though, and which pins to scope, i would be grateful.

[tom66]

Re: Sony KDL-46W5500 got backlights, no picture.

The T-con data output is also LVDS; the purpose of the T-con is essentially to generate the row/column scan and latch signals in sync with "re-timed" LVDS data. (Hence "timing controller"). If you see no LVDS out, check the crystal on the board, and all voltage regulators/buck converters.

[dskall]

Re: Sony KDL-46W5500 got backlights, no picture.

Hey tom66 have you thought about writing a book on plasma tv repair. Explaining how they work and troubleshooting?

[tom66]

Re: Sony KDL-46W5500 got backlights, no picture.

Hey tom66 have you thought about writing a book on plasma tv repair. Explaining how they work and troubleshooting?

Yes and I gave up because I didn't have the time.
There is far too much to explain.

[dskall]

Re: Sony KDL-46W5500 got backlights, no picture.

Maybe some short guides on specific components.

[tom66]

Re: Sony KDL-46W5500 got backlights, no picture.

Maybe some short guides on specific components.

I've already posted several.

[nomoresonys]

Re: Sony KDL-46W5500 got backlights, no picture.

Could be the tcon, shop jimmy is out of stock, some on ebay, took a quick look, saw one for 28 dollars or so, there's probably more there, just took a fast look.

[Th3_uN1Qu3]

Re: Sony KDL-46W5500 got backlights, no picture.

Received a new Tcon - still no picture.

[dskall]

Re: Sony KDL-46W5500 got backlights, no picture.

I have a tv that has a separate frc. I saw data going in but nothing coming out so I replaced frc. Still have same problem. So I wonder if main board needs to send enable signal to enable board. You have checked new t-con to be good?

[nomoresonys]

Re: Sony KDL-46W5500 got backlights, no picture.

Did you ever figure out what was wrong?

[Th3_uN1Qu3]

Re: Sony KDL-46W5500 got backlights, no picture.

No, we gave it back and the boss put the replacement Tcon up for sale.

[nomoresonys]

Re: Sony KDL-46W5500 got backlights, no picture.

Ok thanks.