Samsung pn50a450 panel lit no video

[microvibe]

I have samsung pn50a450 panel lights up no video but sound when boots up.
I have all voltages vsc vs VA etc . Disconnected cable from main board to control board jumper pin 3,4 panel just stays lit no test pattern . Is it common for control board to go on these or any other possibilities?

[ReeceyBurger123]

Re: Samsung pn50a450 panel lit no video

Did you connect the control test pattern pins properly ?

[microvibe]

Re: Samsung pn50a450 panel lit no video

I did pin 3/4 tried all 4 pins as well.

[ReeceyBurger123]

Re: Samsung pn50a450 panel lit no video

Hmm seems like the control board is the issue then but could also be an address buffer fault. Have you a scope ?

[microvibe]

Re: Samsung pn50a450 panel lit no video

No scope if I disconnect the buffers would a picture show up?add duress buffer along bottom?

[tvtimmy]

Re: Samsung pn50a450 panel lit no video

I had a samsung plasma that had screen glow, but no display and it ended up being a surface mount fuse on the board wired to the y-main. I cant remember the model number though.
All I remember, there was a fuse that was open. Maybe check if you have such a fuse where the y-main has a connector going to a bottom buffer board. It was easy to get to.

[microvibe]

Re: Samsung pn50a450 panel lit no video

This one buffer and ysus are attached

[heavymachines]

Re: Samsung pn50a450 panel lit no video

How about some pictures of back of TV clear and focused straight shot pics? That will get you considerably more help and help others help you. Please read the stickies before you made this thread. Thanks....

[ReeceyBurger123]

Re: Samsung pn50a450 panel lit no video

No not the Ybuffer the E or address buffer mounted at the bottom of the panel check the fuse on that. Then check if Va is getting to the address Pcb this is provided by the Ymain.

[microvibe]

Re: Samsung pn50a450 panel lit no video

Ty Reece didn't think to check if VA was at address buffers . Checked voltages everywhere else . Screen dims and brightens as I switch inputs led is blinking on control boards .

I do usually post photos can upload photos if that helps

[microvibe]

Re: Samsung pn50a450 panel lit no video

Here pic

[microvibe]

Re: Samsung pn50a450 panel lit no video

Wouldn't there still be picture if address board fuse gone. Y main is putting 55v VA to address board . Tested fuse ground to chassis get 55v on bottom of fuse nothing on top. Fuse gone?

[flocko]

Re: Samsung pn50a450 panel lit no video

Yes fuse has blown, DO NOT try to run the set with the metal strip removed from the address buffer it acts as a heat- sink and should not be run without it

[microvibe]

Re: Samsung pn50a450 panel lit no video

No picture at all with address board fuse blown? Thought get distorted pic or something