LN-32A550P3F No screen and squealing

[dcapper]

The blue Samsung led in the center at the bottom lights up and the red power light blinks but no backlight. Then after a few seconds, it starts to squeal. I changed all the power supply caps even though they were not bulged. I metered the coils on the inverter board, and all reading fine. So I found another mainboard that I had. I installed it and went into the service menu to change it to the model I that I am working on. Well now the tv turns on, it doesn't squeal and I get video except the video is red. Is the tcon bad?

[neilc6]

Re: LN-32A550P3F No screen and squealing

Search C102 in the forums since this cap on the main board can cause squealing and green screen.

[dcapper]

Re: LN-32A550P3F No screen and squealing

But I replaced the main board and now I have a red screen. Should I find an old Samsung mainboard and replace C102 on the board I pulled out?

[R_J]

Re: LN-32A550P3F No screen and squealing

It could be a mismatch between the main board and t-con, or it could be a service menu setting that is still wrong. Check the other settings in the service menu IE: LVDS OUT Format, Panel Option.

The cap at location C102 is only on a certain main boards, not all of them.

This thread has pictures of the main board and the model: https://www.badcaps.net/forum/showth...highlight=c102

[dcapper]

Re: LN-32A550P3F No screen and squealing

I wish I knew what the original settings were. I'm going to look at some old Samsung mainboards I have laying around and change the cap on the original board.

[dcapper]

Re: LN-32A550P3F No screen and squealing

Do these settings look right? Maybe I'm missing something.

[nomoresonys]

Re: LN-32A550P3F No screen and squealing

Too hard to see the settings, it's sideways.

[dcapper]

Re: LN-32A550P3F No screen and squealing

I know I'm trying to set it straight. Let me repost.

[nomoresonys]

Re: LN-32A550P3F No screen and squealing

Maybe the LVDS out format, make note of what it is now, see if you can change it, on some when you change it the picture clears up and you can see it right then.

[dcapper]

Re: LN-32A550P3F No screen and squealing

I ended up doing Budm's mod on the original board from the other thread. The tv is working perfectly now! The only difference I see is the 32A CV vs. 32A C and Gamma .95 vs. .90

[R_J]

Re: LN-32A550P3F No screen and squealing

So are you saying that your main board DID have the cap at C102?

[dcapper]

Re: LN-32A550P3F No screen and squealing

Yes the original one had the cap so I did the Budm mod. I tried replacing the mainboard originally with one I had but I got the red screen. I couldn't get rid of the red screen so I tried the mod and it worked.

[budm]

Re: LN-32A550P3F No screen and squealing

Just for FYI about NEC Tantalum caps used on Samsung main board:
https://www.badcaps.net/forum/showth...sung+LN52A650A

[nomoresonys]

Re: LN-32A550P3F No screen and squealing

Oh, ok, I read it as neither of your boards had c 102.