LG Plasma 60PN6500-UA Main Board

[ChurchTech]

Hello,

I was given a non-working LG Plasma 60PN6500-UA with the hope that I could repair it and give it a new home.

60PN6500-UA
60PN6500-UA.BUSLLHR
LG EBT62394201 (EAX65071307(1.1)) Main Board

How it died:
Previous owner was swapping HDMI cables and broke the side-facing HDMI jack off of the Main Board. Result is no picture, only red power light.

What I've found:
Removing the Main Board and jumpering the EXT AUTO GEN on the control board yields clean test patterns similar to this (not my video):
https://www.youtube.com/watch?v=9LcqLM5TRHk

I thought I got lucky when I found a board listed on Amazon that was an exact model# match and was produced just 16 digits after the damaged one I have. However, the board that showed up was not the one pictured in the listing (http://www.amazon.com/gp/product/B00YAS31PE).

The item shipped to me was supposedly an equivalent substitute (LG EBT62394292) but it only yields a solid white screen when installed and powered on.

I sent that board back but after reading through these forums I'm thinking that I should have held on to it and tried working through some reset options. I'm not sure though?

The folks at Encompass say only an authorized repair shop/dealer can order the part they have available but I don't even know if that substitute board would work for me.
https://lg.encompass.com/item/102171...assis_Assembly

Any thoughts on where to find a replacement board or if it is possible for a hobbyist to repair the original board?

Peace,
Aaron

[martyparish]

Re: LG Plasma 60PN6500-UA Main Board

If you look very closely, near the broken hdmi there is a resistor(R270) that was broken off too. Maybe replacing that will bring it back. Not sure how to find the value though...

Check out the attached image.

[jetadm123]

Re: LG Plasma 60PN6500-UA Main Board

disregard

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Thanks for the closeup of a comparable board. Great image!

I wondered if R270 was supposed to be occupied but I had not found an image that was good enough to show it.

Other noticeable damage: HDMI contact #3 is missing it's surface and IC204 is shifted slightly in-board (but the soldering seems intact).

I didn't think there was much hope of piecing the old board back together.

Maybe folks around here will know better.

Peace,
Aaron

[martyparish]

Re: LG Plasma 60PN6500-UA Main Board

Yeah I thought the IC looked a bit shifted too. You never know, that resistor could bring it back... Worth a shot I suppose. It actually looks like that resistor is part of the USB circuit but you'd have to confirm that.

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Ok, so what are the realistic chances of finding out the value of that resistor?

Peace,
Aaron

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

I got a line on a possible replacement board in this thread:
https://www.badcaps.net/forum/showthread.php?t=47843

I'm still interested in learning more about possible repair of the damaged board pictured above.

Peace,
Aaron

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Ohmed out the connections around the missing resistor on the USB power controller/switch.

IC204 reads: D82 | 020 | LU
I haven't been able to track down any specs on it.

The missing resistor, R270, appears to be in series with R264 between pins 4 & 5 of the USB chip.

R264 measures 10KΩ.

R271 measures 40Ω and has continuity with pin 4
R258 measures 40Ω and has continuity with pin 5

Pin 1 has continuity with ground and one side of C201.
Pins 2-3 have continuity with the other side of C201.
Pins 6-8 have continuity with one side of C213 and the +5V pin on the USB port.

Any suggestions on what R270 might have been?

-Aaron

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Tracked down the datasheet on the IC:
https://cdn.badcaps-static.com/pdfs/...fca8aa9d5d.pdf

Image of typical application circuit seems to match what LG did on this board.

[jetadm123]

Re: LG Plasma 60PN6500-UA Main Board

A quick look at the spec sheet indicates that chip is used specifically for USB applications with the resistor value in question used in the application circuit at 10k-100kohms. My guess is that R270 wasn't even used. The solder points for R270 look too rounded off to have had anything soldered in that spot. I suggest you solder in another HDMI socket and go for it.

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Based on Marty's shared image above (https://www.badcaps.net/forum/showpo...96&postcount=2) and close inspection of the points it does appear that a resistor belongs at R270.

Also, I still have the original HDMI socket which looks like it is in good enough shape to remount.

Just guessing here but the deeper question I have is does the possible missing resistor or missing HDMI socket likely lead to a dead board?

Seems like a missing resistor in the 5V circuit could shut everything down, not sure if a missing HDMI socket could go unnoticed or not.

[jetadm123]

Re: LG Plasma 60PN6500-UA Main Board

Okay, I guess I misread your original post. I thought the owner had physically damaged the original HDMI port and you were in the process of replacing it with a new one. I didn't realize he pulled the entire socket off. If the solder pads for the HDMI socket are still good, go ahead and solder the original HDMI socket back on. As for R270 missing, it means you have a non-working USB port. I would think it will not interfere with the functioning of the HDMI port. The only way you're going to find if the main board is good is to solder that HDMI socket back on and hook everything up and give it try.

[martyparish]

Re: LG Plasma 60PN6500-UA Main Board

Throw a 10k on there and see what she does! If nothing, solder that hdmi on there and try again. It won't cost a dime(assuming you can scrounge a resistor).

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Thanks for the push to give it a try!

I scrounged a 10KΩ resistor off of an old graphics card I had laying around.

Soldered that in the best I could, made sure it wasn't bridged directly to R264 and between the ends of R264 and R270 I show 19.9KΩ where before it was open.

Also remounted the HDMI socket.

No luck on power-up though.

However, after trying all of that, I did end up finding a service manual online and Marty you guessed right about the resistor value... 10KΩ is correct! (see attachment)

Who knows what other damage may have occurred when the HDMI got slammed into R270 and IC204.

I'm going to go through the service manual and see if I can discover any other possible fixes based on what voltages are present when the board is out and the test patterns run cleanly vs. when the board is in I get zero start-up.

[mmartell]

Re: LG Plasma 60PN6500-UA Main Board

It looks like this has the hdmi controller integrated into the uP so my guess is that internal controller got shorted long enough to damage it - they are very sensitive. As a result the processor is probably non functional and being a bga package would be a bitch to replace even of you had another one.

[martyparish]

Re: LG Plasma 60PN6500-UA Main Board

Nice job too bad it didn't work... mmartell is probably right about the processor.

It was certainly worth a shot! I guess you'll have to stay on the hunt for the replacement board. You planning on keeping the 60? THat's a big boy!

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Well it was "free" and if PartStore.com can come through with the same board that saved Bob's (https://www.badcaps.net/forum/showthread.php?t=47843) then I think it is worth $116. I've heard big plasmas are not so easy to come by.

Nothing ventured, nothing gained.

Thanks for all of the advice so far.

I'll report back whether or not I'm able to get it working and mounted.

[Malachi]

Re: LG Plasma 60PN6500-UA Main Board

I have a 60pn6500 that I needed to find a main board for. I had a hard time locating one, I took a chance on one for the 50pn6500 and it works. Been working for 2 months no problem.

I threw away the old one but I guess I should have kept it. You never know..

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Thanks for the tip Malachi! It's good to hear from another user with the same model who has had a successful board replacement.

There are a lot of parts sites that list 5-10 LG models as all taking the same board. The problem seems to be the number of versions that LG went through within these models.

After getting burned once on wrong version number I'm giving another one a try based on a BC board member's success story. That board is supposed to arrive on Monday, 03/14.

If it works I'll post the results. If it doesn't I will check back with you to see which exact part number worked successfully in yours. (If you still have access to the part number.)

[ChurchTech]

Re: LG Plasma 60PN6500-UA Main Board

Thanks to this great forum I now have a working 60" LG Plasma.

The Main Board (EBT62753601) from the source provided by Bob solved the issue.

Thanks to everyone who helped out!

Peace,
Aaron