Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

[tidar]

Hi I have Panasonic TH-50AX800F.
The screen only showing vertical lines like this .
I'd like to ask whether it is the power supply board issue or not, the only image that I found that similar to my problem was the one from　budm. I'm only a regular tech user without any background in tv services so I decided to order a new power supply board (TNPA5937 3P) but it takes forever to come and returned to the sender for some reason. So I have to try fix it by myself. What is actually the source of these vertical lines? The sound is okay, when I turned on it showed panasonic logo but turned into this rainbow screen again instantly.
Thank you very much !!!!

[dick_barton]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Can you post pictures of the circuit boards and how they are connected together.

[Th3_uN1Qu3]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Not power supply. Mainboard or Tcon fault, leaning towards Tcon. Agreed with the above member, show us some pictures of the boards inside the TV.

[tidar]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Thank you for the responses.
I've changed the T-Con board and it has still the same issue.

[freakaftr8]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

You changed the tcon or the sub (FRC) tcon? The main tcon goes directly to the panel. The
FRC is the board in the middle before the tcon. I'd try using heat on the processor on the mainboard.

[tidar]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

You changed the tcon or the sub (FRC) tcon? The main tcon goes directly to the panel. The
FRC is the board in the middle before the tcon. I'd try using heat on the processor on the mainboard.

Yeah I changed the bigger one on the middle.
Do you mean by applying direct heat to the processor by solder?
Thank you for your reply.
I've attached the pic of the mainboard as well.

[freakaftr8]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Actually try freeze spray. I have a feeling this is a heat related failure. Use this on the rectangular ram modules around the main processor.

Also you could try disconnecting the right 2 ribbons from the tcon to panel. If same issue occurs, try disconnecting the left two. I'm talking about the white cables with the blue ends that di directly to the LCD panel.

On a side note I find it interesting that the panel is a Samsung and the tcon is Innolux.

The reason I'm thinking heat related failure is because you will see the logo for a second before the failure.

[freakaftr8]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Use freeze spray on the locations I have provided

[tidar]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Actually try freeze spray. I have a feeling this is a heat related failure. Use this on the rectangular ram modules around the main processor.

Also you could try disconnecting the right 2 ribbons from the tcon to panel. If same issue occurs, try disconnecting the left two. I'm talking about the white cables with the blue ends that di directly to the LCD panel.

On a side note I find it interesting that the panel is a Samsung and the tcon is Innolux.

The reason I'm thinking heat related failure is because you will see the logo for a second before the failure.

Thank you very much for your helps! I'll get the freeze spray and try it, as you mentioned about the heat related failure. I realized that the paste(idk what's it called) was burned and melted, could this be affecting the failure as well?
Thank you!

[freakaftr8]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Ah! Could you post a closer focused picture of IC1803? It certainly looks like it is bad. It appears to be a voltage regulator. There is probably your problem tith the tv and in this case we wont need the freeze spray.

[tidar]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Yeah sure, thank you in advance.
I've tried to disconnect the ribbon cable and when disconnected, the half of the screen went blank *only white screen.

[freakaftr8]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

Does ic8303 look like it has a small hole in it? That's the 1.1v to the processor core voltage. It looks blown. Can you read the numbers etched into that ic?

[CapLeaker]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

it looks to me too that ic1803 is blown. Pic isn't clear enough, but it surely looks that way.

[tidar]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

I couldn’t see the number at all. Because the paste melted and covered it, and yeah a lil bit part of it was chopped off too. However, I took the more clearer picture.

[CapLeaker]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

the IC is too dark on that pic for me to see.

[tidar]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

the IC is too dark on that pic for me to see.

Yeah it's burnt out, it seems

[freakaftr8]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

In this case the main board is your problem. I would definitely either replace it or try to find out what's that IC is yet at least try to replace that if you feel comfortable with soldering.

[tidar]

Re: Panasonic TH-50AX800F. rainbow screen-Power supply board issue ?

In this case the main board is your problem. I would definitely either replace it or try to find out what's that IC is yet at least try to replace that if you feel comfortable with soldering.

Thank you so much for your response!
Luckily I found someone who wants to sell the exact same tv with broken screen, maybe I can take the main board for replacement.
Will update it later.