Another Sony Bravia 46" KDL-46S4100 No Picture or Sound

[Festus440]

Hi. Yet another Sony Bravia. Seems like there is a lot of these with problems. I hope somebody can help me with mine. This TV developed some horizontal lines on the bottom of the screen. A couple of days later the video stopped working. I was ready to junk it until I found this forum. So here are some details:

The backlight is on and visible through the back. The LCD is always totally dark and blank.

Sometimes I have been able to get audio through it, but usually not. The last time I did, it seemed like the volume buttons weren't working either.

I tried to wiggle the cable to the T-Con board and it has no visible effect on the LCD.

The fuse on the T-Con board checks good. The voltage to the T-con is slightly low (11.5 Vdc)

Checked a bunch of voltages on the G board and they are also slightly low but I would say probably okay.

The buttons (except power) basically seem to do nothing except the channel buttons make the backlight flicker a little.

I'm thinking this is a main board problem even though the problems I've read about here seem to usually point at the LCD panel or the T-Con. Is there any way to be sure? The main boards are pretty pricey. I hate to sink that much money into this if the panel is shot.

Any advice is greatly appreciated!

[alexanna]

Re: Another Sony Bravia 46" KDL-46S4100 No Picture or Sound

I am fighting a similar problem on a Sony model television like you have, The model number is very similar although it not an exact match.
On mine there was some rainbow colored lines on the right outer end of the screen and the right side of the picture is shadowy. I did try the placing insulation on the bonded tabs to the LCD.This made a difference on the picture but the right side of the screen is still darker, and shadowy.
I think the common problem we have is sometimes when powered on I can tell the backlights are on but it's a bluish/gray screen.
I see some questionable aluminum caps on my signal board, they are 25v 220uf,they don't look very fun to change, Also on the P/S there is a Huge 25V 3300uf cap that looks like it may be starting to bulge.
If you could post some pictures of your boards, if they are similar I would point them out.

[Festus440]

Re: Another Sony Bravia 46" KDL-46S4100 No Picture or Sound

I have attached a photo of my supply board. Looks like Nichicon caps and they look healthy to me. As I mentioned, the voltages seem pretty close. I never had an issue with the LCD being slow or dark. I just remembered another symptom. It would a times get fine short lines on the left and right vertical edges of the screen with HD signals.

Thanks,
Bob