LG 60PA5500 Turns On Then Off

[yompi]

I have a 60PA5500 and I am having some issues.

When I first plug it in, it makes a click noise (not sure if this is normal or not).

Then when I try to turn it on, it clicks once like it's turning on, then it immediately clicks off.

Interestingly enough, if I leave it unplugged for a few minutes or an hour, it'll start working again perfectly. I can turn it on and off as much as I want and use it all day. It'll click when I turn it on and when I turn it off.

But when I shut it off for the night and come back in the morning, it goes back to clicking off as soon as I turn it on.

This sounds like a bad capacitor to me but upon visual inspection of the power board and all other boards, all the electrolytic and film capacitors look fine to me.

Could this be a bad Y-SUS or Z-SUS or mainboard instead?

Or could it be the C802 capacitor that a lot of people with the 50PA5500 have had success with replacing? The power board between the the 60PA5500 and 55PA5500 are a little different but the 60PA5500 does have a C802 near the top in a similar location.

If it does sound like the capacitor, how do I know which one to order? It might be different than the 50PA5500 one.

Any input here would be greatly appreciated.

Thanks

[Hamie]

Re: LG 60PA5500 Turns On Then Off

Upload pictures of all the boards.

[mmartell]

Re: LG 60PA5500 Turns On Then Off

Try heating the main board in the morning with a hairdryer and see if it starts up ok first try.

[yompi]

Re: LG 60PA5500 Turns On Then Off

First of all, thank you for the quick replies. I really appreciate the help.

Ok so I went to sleep last night with it in working condition and I left it plugged in to recreate the problem this morning.

I have attached the pictures as requested.

The 2 red lines you see on the overall picture is what I already did as troubleshooting to (hopefully) rule out the y and z sustain boards (I think that's what they're called).

When it wasn't working this morning, I unplugged the TV, then unplugged one of the marked cables from the power board, plugged in the TV and it still wouldn't turn on.

Then I did the same for the other marked cable. So I think that rules out a few things but correct me if I'm wrong.

At that point I unplugged it (for maybe 10 minutes) to take pictures and when I plugged it back in it started working so I was unable to heat up the motherboard to test that. What makes you think this could work though? Would I apply the heat to a specific component?

Does all this mean that it's either the power board, motherboard, or little green board between the power board and mother board?

Not entirely sure where to go from here.

[mjaklrsav]

Re: LG 60PA5500 Turns On Then Off

I also have LG 60PA5500 that shuts down, but prior to shutting down, the screen is snowy white. My TV shuts down in 1-4 seconds, and sometimes it just stays on with the static white screen where I can barely make out the screen.

I replaced the Main Logic board but it still has the same symptoms.

The C802 cap show thinner ban in the middle with expansion at ends.

I have gone on other forums and could not find any root causes.
Thanks

[yompi]

Re: LG 60PA5500 Turns On Then Off

That seems to be a different issue than mine. Maybe it's one of the sustain boards for you.

Mine works perfectly when it works. The issue for mine is with turning it on.

[Andrew F. Ali]

Re: LG 60PA5500 Turns On Then Off

If you have a 'good' replacement for C802...try that first....look for cold solder joints on your Pwr Bd....if the problem persists...then I would suspect the Main Bd.....look for cold solder joint on the main Bd, too.

[mjaklrsav]

Re: LG 60PA5500 Turns On Then Off

Is the C802 a 0.022uF 1.25KVDC like on the 50PA5500?

The value is not veiw-able due to the glue attachment. Before I separate the components, I was hoping someone knows the value.

[yompi]

Re: LG 60PA5500 Turns On Then Off

Thanks for chiming in.

I will take off the motherboard and powerboard today and look for bad solder points.

In the mean time, how can I find a good replacement for the C802? I googled the 2 things it says on the capacitor but I couldn't find anything. The capacitor has these 2 lines on it:
333hs1600v
nppsc03pp

The only information I can comprehend from this is that I need a 0.03uF film capacitor that is at least 1.6kv (2.5kv works too?). But I am not sure at all about this so correct me if I'm wrong here.

Also, appearance wise, there is nothing wrong with the capacitor. Is it possible it's still bad?

[Andrew F. Ali]

Re: LG 60PA5500 Turns On Then Off

Yes...if you can get a 0.03uF 2.5kV cap...non-polarized....this will work as well.

[yompi]

Re: LG 60PA5500 Turns On Then Off

Do you think it's a bad C802 capacitor?

What I can't seem to figure out is why it sometimes works and sometimes doesn't.

[mmartell]

Re: LG 60PA5500 Turns On Then Off

Because they can get flaky before they quit altogether. And putting heat on them will sometimes reveal it by making it work again while it's warm.

[mmartell]

Re: LG 60PA5500 Turns On Then Off

The reason I want you to heat the main board is to check if the processor is not making good contact due to its bga solder balls under it.

[yompi]

Re: LG 60PA5500 Turns On Then Off

Sorry for the late response. I got busy with the fall sesmester starting.

Anyways I still want to get to the bottom of this strange problem. I've been using it these last few weeks and same thing has been happening. For a while it was turning on and off perfectly but again it's back to its old ways. It's even worse than it ever was now. Now it's extremely hard to get it to turn on whereas before I could at least get it to turn on and work for me with a little fiddling.

I tried heating up the main board with a hair dryer as you said but to no avail. I still think it's something on the power board because when it works, it works fine. It'll never shut off while I'm using it. Something is preventing it from starting up consistently.

What bothers me is that none of the capacitors look faulty. For the 50 inch version of this TV, people with the same symptoms had success by replacing the C802 capacitor. Only thing is o haven't seen anyone with the 60 inch have the same solution and that the 50 inch people's TVs weren't turning on at all whereas mine sometimes turns on.

Anyways, I ordered the part below and will replace the C802. Does that look like what I need? Does this sound like the problem or could it be something else entirely?

Thanks
yompi
http://www.digikey.com/product-detai...03J-ND/3102596

[yompi]

Re: LG 60PA5500 Turns On Then Off

So the part came in today...however it appears to be about half the size physically of the one that's already on there. Do I have the wrong one? Or could it be that this one is just smaller physically? They're both red film capacitors with the same shape. Just this one is smaller.

[ReeceyBurger123]

Re: LG 60PA5500 Turns On Then Off

If its the same value its fine.

[yompi]

Re: LG 60PA5500 Turns On Then Off

Sounds good. I will replace and see what happens

[yompi]

Re: LG 60PA5500 Turns On Then Off

Replaced and same issue

[yompi]

Re: LG 60PA5500 Turns On Then Off

Update:

I bit the bullet and eplaced the whole power board for $60 and the tv is working like new again, which I'm excited about.

However, I'm still really bothered by the fact that I have this board where sometimes my TV powers on and my TV will work flawlessly as long as I leave it on. The only thing is it doesn't turn on sometimes. And that sometimes recently turned into most of the time.

I checked all the diodes, resistors, and rectifiers on the new board vs old board and everything is the same. Everything was tested in circuit. Theoretically though none of these parts should've been bad anyways because if they were, the TV wouldn't turn on at all.

Does anyone have any possible idea what in the world could be bad on this board causing it to power on sometimes and not other times? I already replaced the c802 as I said earlier but I really just want to get this working since it has to be one or two components that are bad. It could be a good replacement board for someone else.