JLC37BC3000 strange issue with mainboard replacement

[sammy76]

Ok so I have a jvc that had all the symptoms of a bad main, turns on shows jvc logo and then blank screen with backlights on but unresponsive to any buttons. Order a new main and exact same symptoms. Seller agrees it's most likely the main and ships out a new one. Install and almost identical symptoms.

Still shows jvc logo and goes to black screen, however I noticed if I hit channel up or down the right before it shuts down it will respond with a delay. It's almost like when your PC memory is full and lags out. Is this symptomatic of a second bad main? Or should I be suspecting power issue? Any help is appreciated as I really would like to get it fixed but haven't a clue where to start testing.

[mmartell]

Re: JLC37BC3000 strange issue with mainboard replacement

Sounds like a bad main to me. Search shopjimmy for that board - sometimes when a particular board is nearly impossible to find it's because they all have the defect that makes them disappear.

[sammy76]

Re: JLC37BC3000 strange issue with mainboard replacement

Damn, that's the same conclusion I came to. I was just hoping not as both boards I got from the seller did the same thing. Is there some special procedure to initialize LG mains after replacement?

[mmartell]

Re: JLC37BC3000 strange issue with mainboard replacement

Try heating up the main with a hair dryer for 30 seconds and then power on. If your symptoms change you will know for sure where the problem lies and even if you can do something about it.