50PB560B -LG common problems?

[diif]

Re: 50PB560B -LG common problems?

It looks like you need an oscilloscope for those last three tests.

[Demonata08]

Re: 50PB560B -LG common problems?

Dont suppose anyone has any wisdom for me at this point? I realized my pictures didnt upload so here they are

[Demonata08]

Re: 50PB560B -LG common problems?

I really hate to keep posting but im not getting any replies. And im still trying to actively repair the board since the replacements are stupidly high. So i double checked the panel and all other boards are good. I got the test patterns on and it was working well.

In the attachment is troubleshooting steps from the LG, Since the IC replacements ive gotten all the proper voltages on everything on the list except maybe to the main IC. it was showing 3.3v but i got 3.2v which i think is close enough? I checked the regulator and its putting out a perfect 3.3v.

Ive made it down to checking the clock speed at X400 for 24mhz. I have no idea how to go about that. the other two are to check signal transitions at different places which i dont know how to do that either.

So what component should i be looking at? Theres a few on here that i suspect and would like to test. I'll mark them on a reupload of the main. its the ones between the red lines.

I feel like theres so many of these TV's with main board issues. Every time i search its model the majority of them have the same issue but no solution. With the schematic i feel like we can figure this out.

[Demonata08]

Re: 50PB560B -LG common problems?

You could try this repair kit for your 50" LG plasma model 50PB560B:

https://www.shopjimmy.com/lg-ebt6285...0pb560b-ua.htm

I have a similar problem with 60" LG plasma model 60PB5600... My 60" model has only one rear HDMI port, and they were notorious for poor solder. The HDMI port broke off completely when an HDMI cable was inserted. As a result, something was shorted out and damaged the main 156-pin IC LGE8220. I suspect you may have same problem.

Try holding your finger on top of the large LGE8220 IC and see if it gets hot.

You could try replacing the main IC, or buy the kit and replace all 3 ICs.

I doubt reflowing will solve your problem.

Tried the repair kit. No dice.

replaced all three IC's in the repair kit. cant even get an error code of any sort unless there is no power to the main.

when its all plugged up it does nothing when you hit the power button. That repair kit had a new eeprom, a chip for what i think is audio, And the new main IC.

the ic doesnt get hot or anything. i checked to be sure the button was having a voltage fluctuation when pressed and it was working.

These mains are way to expensive to really be worth it. anymore tips? I went through the the voltage regulators both were working i believe. it 5.2 to 3.3 and 5.2 to 1.8.

[Demonata08]

Re: 50PB560B -LG common problems?

Another question, Is there anyone that might know what voltage the RL_ON line would suppose to read? Im tracing the issue right now, the specs on the p board dont say. just says rl_on where it normally says voltage. The schematics i linked dont say either. under troubleshooting it just says to check the voltage

I'm getting .35 volts on that line. On some of the IC's that say it should be receiving 5volts its also getting .35 volts which leads me to believe that maybe needs to be 5volts. But im not sure.

thanks in advance

[Demonata08]

Re: 50PB560B -LG common problems?

Thanks for pointing me in that direction man! I agree that i believe it might be the main IC. But is there anyway to test? I feel like i should be able to since i have the actual diagram in front of me. But my hands are way to shaky to test points that small. Ill link the diagram below, and the manual also, if anyone smarter then i could follow through to a test point that might be a little easier, I would greatly appreciate it

Main IC
Service Manual

[Unspun01]

Re: 50PB560B -LG common problems?

You could try this repair kit for your 50" LG plasma model 50PB560B:

https://www.shopjimmy.com/lg-ebt6285...0pb560b-ua.htm

I have a similar problem with 60" LG plasma model 60PB5600... My 60" model has only one rear HDMI port, and they were notorious for poor solder. The HDMI port broke off completely when an HDMI cable was inserted. As a result, something was shorted out and damaged the main 156-pin IC LGE8220. I suspect you may have same problem.

Try holding your finger on top of the large LGE8220 IC and see if it gets hot.

You could try replacing the main IC, or buy the kit and replace all 3 ICs.

I doubt reflowing will solve your problem.

[Demonata08]

Hey everyone again, Been a few days. My newest project is an LG 50PB560B. Which actually has a very easily accessible service manual(which was nice).

So the initial problem is no power on. This model doesnt seem to even have a standby light. Tested all the power points and everything matched perfectly. Unplugged power board from main and the screen will come on. (i understand theres some way to get test patterns up but i havent figured that one out yet)

I'm highly suspecting the main. The board itself is a pretty simple looking board. but its going for 300 on ebay so not worth it. Im looking at reflowing it, i have everything i need to do that although im not experienced at all at that(Gotta start somewhere?)

Anyone know of the common chips to be looking at on this one? I have the diagrams to actually trace the problem but the test points are so tiny im sure ill short something. If anyone has any idea of the best plan of attack for this one id greatly appreciate the support