# Free LG 42LC7D Black Screen (No picture) fix?



## sktfreak

bump.


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## sktfreak

bump...


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## Rbby258

needs new caps, probably only one


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## Jayjr1105

Are you sure the solder is flowing into the circuit board. Replacing cap's isn't that easy. Have tried it on a couple motherboards with no luck because the solder wouldn't flow into the hole making contact with the multiple layers. Also might have another bad cap somewhere else. For future reference, just pull off the bad caps with pliers leaving their leads attached, then just twist or solder the new ones on for testing.

Edit: Also, the polarity of the cap is very important as well. make sure your + and - 's are the same way the old ones were.


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## sktfreak

Quote:


> Originally Posted by *Jayjr1105*
> 
> Are you sure the solder is flowing into the circuit board. Replacing cap's isn't that easy. Have tried it on a couple motherboards with no luck because the solder wouldn't flow into the hole making contact with the multiple layers. Also might have another bad cap somewhere else. For future reference, just pull off the bad caps with pliers leaving their leads attached, then just twist or solder the new ones on for testing.
> 
> Edit: Also, the polarity of the cap is very important as well. make sure your + and - 's are the same way the old ones were.


I double checked the solder after I soldered them in and went over everything twice, re-soldering to make sure. I have re-soldered caps quite a lot on other things, and I do have a PCB soldering iron to make it easier (smaller tip).

Haha yes I do know about polarity. The first time I ever replaced caps on something I didn't, and a few exploded. It was pretty awesome to watch.


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## Rbby258

Quote:


> Originally Posted by *sktfreak*
> 
> I double checked the solder after I soldered them in and went over everything twice, re-soldering to make sure. I have re-soldered caps quite a lot on other things, and I do have a PCB soldering iron to make it easier (smaller tip).
> 
> Haha yes I do know about polarity. The first time I ever replaced caps on something I didn't, and a few exploded. It was pretty awesome to watch.


sooo... did it work?


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## sktfreak

Quote:


> Originally Posted by *Rbby258*
> 
> sooo... did it work?


The stuff about double checking was past-tense. I already tried it before I made this thread.


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## Rbby258

Quote:


> Originally Posted by *sktfreak*
> 
> The stuff about double checking was past-tense. I already tried it before I made this thread.


oh so it didn't fix then, replace all the caps


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## sktfreak

Just replaced the last of the caps, still same problem


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## sktfreak

Just an update. On the main board there is a green button, if I press it while the TV is on, pink & red diagonal lines flash on the screen and then flash off, and the speakers make a noise too... is this of any help?


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## sktfreak

bump


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## sktfreak

bump....


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## Rbby258

driver board gone im guessing


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## DzillaXx

Just go on ebay and buy a new main board


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## sktfreak

Ok... I'll order one and see if that fixes it. If not, any other suggestions?


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## sktfreak

I stumbled across something last night.

Found a thread on another forum where this guy has the same TV, same mainboard, has done everything in THIS thread and has EXACTLY the same issue.
Looks like the problem is a software lockup caused by a write error, when RGB mode is on and the TV gets turned off. A firmware update should fix it. Now to find a serial cable and give it a shot, hopefully, that will resolve the issue.


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## Rbby258

surly a new main board would have also worked


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## sktfreak

Quote:


> Originally Posted by *Rbby258*
> 
> surly a new main board would have also worked


A new main board will cost ~$70 + shipping (can't get any in Australia <$200... shipping to AUS is $30-$50) so it's an expensive exercise. So I'll try the serial cable method first.


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## Rbby258

or give up tv's are cheap now even in uk where we also get screwed on anything that involves money


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