I fixed the issues by reflowing the entire main board.
I did this in the oven at 190 degrees Celsius for 10 minutes. Before putting it in, I removed all the rubber and plastic parts from the board. I created feet for the board to elevate it off the tray (using four balls of aluminum foil on the corners and one in the middle to prevent warping). I also applied flux to all the larger chips. I suspect that the issue was with IC 3000, a processor that supplies the drive-on signal, but I thought it would be worthwhile to apply flux to everything.
I reconnected everything, and to my surprise, it worked!
I'm not sure how long this fix will last, but at least it's functional for now.
By the way, I realized that the part number of the board is EAX65608606. I can find a replacement AU version for $300 AUD, but I found a CA version for only $38 AUD on Taobao (the Chinese domestic market version of AliExpress). If the TV breaks again, I might try the CA board. From what I can see, there's an extra antenna port on the CA version, which I'm not sure what it's for (perhaps for cable TV, which might be different in Australia).
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crwdns2944067:04crwdne2944067:0
Hi @gavingrech
Did you try searching online for the mainboard model number?
This is either stamped on the board or perhaps on a sticker on the board It could look something like EBU62421841 or similar
Sometimes a board may be compatible with a few models but the seller may not list your model as they are unaware of this.
If you do find one make sure that it is the exact same number and version as the original as sometimes earlier versions may have problems that have been overcome in later versions
crwdns2934271:0crwdnd2934271:0 jayeff crwdne2934271:0
@jayeff the part number is EBU62421841 but I can’t find anyone that sell them (all pages say unavailable) I did find one from Malaysia that is second hand and untested, but not willing to pay $250 AUD on a part that my not work.
crwdns2934271:0crwdnd2934271:0 Gavin Grech crwdne2934271:0
@gavingrech
Looks like you're out of luck, unless you can find the same TV with a broken screen that's being sold for parts.
I've looked on the obvious places but again there's nothing there either.
crwdns2934271:0crwdnd2934271:0 jayeff crwdne2934271:0
I have found these 2 videos the first is a LG TV that seems to have the same error. He replaces the board but I think he indicates that 2 chips are the issue (the video is not in English so I am trying to understand from actions). The second is a different brand but the same issue. In this video, he indicates that the heat from the TV warps the board and he just re-solders the chips. I will give this a go, hopefully it works.
https://youtu.be/ETgs6kc1ze8?si=SR-YXy8T...
https://youtu.be/O1XGwQszLrc
crwdns2934271:0crwdnd2934271:0 Gavin Grech crwdne2934271:0