Toshiba 37AV50U - Distorted Picture

[Dgtech]

Ok, this one was a repair. At first, the set was turning on (LED changes state from red to green) without any picture at all. After troubleshooting, I narrowed it down to the mainboard. I replaced it and now it turns on with the picture below. OK, now it looks like it may have a bad Tconn as well. I swapped the Tconn, no change. Just for the heck of it, I ordered another mainboard, no change.

The only two boards I didnt change were the power and Inverter but I can't see how they could affect this.

[tom66]

Re: Toshiba 37AV50U - Distorted Picture

A bad power supply could cause this problem. One particular case I dealt with was a low 5V rail causing the T-con to get a bit dizzy. It caused similar effects to what is shown in the picture.

[Dgtech]

Re: Toshiba 37AV50U - Distorted Picture

Thanks for the reply, I will recheck the 5V.

[tom66]

Re: Toshiba 37AV50U - Distorted Picture

Thanks for the reply, I will recheck the 5V.

Check other rails, too. A low rail could be causing a buck converter or LDO on the main board to drop out of regulation.

[Dgtech]

Re: Toshiba 37AV50U - Distorted Picture

I checked all rails.All power seems normal on regulators on mainboard.