LG 42PJ350 Starts, Shuts down, won't restart

[marty-clubber]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Hi repair kit power supply LG 42PJ350
r927 22ohm resistor
r929 22ohm resistor
ic301 3br1565jf regulator
d304 diode
easy repair thought was the fault on mine but ended up been ysus board there no repair kit.

[dkneyle]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Probably worth changing over D304 just to eliminate that possibility. I wonder what type it is? Be aware that they are almost always fast-switching types. (I made the mistake once of replacing with a general purpose power diode - big mistake.)
I too was starting to wonder if it was something off board that was causing a shut-down?
I have the Training Manual for this model but it's about 16MB. I suppose I could post it to DropBox or something? PM if you like and we'll see how we could do that. It has good instructions for how to test the power supply for operation. You could load up the power supply without the other boards attached to it and see if it stays up and running or if it powers down after 40 minutes. Then you know whether you have a power supply fault or something else.

[Amraks]

Re: LG 42PJ350 Starts, Shuts down, won't restart

hey dkneyle I will send you a PM you can email 16mb file ill upload it to my free webspace that comes with my internet.

[Amraks]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Here is the training manual thanks to dkneyle for providing it.

[Amraks]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Today the tv has been running along time.
I think it was a dry joint on the new regulator causing the issue, it had a blob on the outward most leg on topside of board must of applied to much solder.

Will soak it all day tomorrow with Back Cover on.

fingers crossed.

[Amraks]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Yup tv is repaired, Soaked it all day today with back on.

I figured out the screws were not grounded the other day as there was a loose screw when I was checking stuff.

[51k.bos]

Re: LG 42PJ350 Starts, Shuts down, won't restart

HI, I know this is an old thread, but since it isn't closed I thought I would try here before creating a new one.

I also have an LG 42PJ350 that is exhibiting the same symptoms, albeit slightly different. My particular tv will sometimes run for only 20-30 minutes, other times running for 3+ hours before cutting off, and then doing the clicking thing when trying to restart it. I have let it sit for days, only to get maybe 20 min of run time without it coming on until the next day. But then sometimes I've only let it sit for an hour or so and have gotten 3+ hours of run time. There doesn't seem to be any rhyme or reason to it either. It's not a progressive thing because it goes back and forth from running for a short to long time intermittently.
From the posts that I've read, I'm seeing that replacing 3br1565jf might fix the problem. I wasn't sure , however if the disparity in run times was perhaps a different issue all together or something else in addition to replacing that part. I thank you in advance for your time and assistance.

[dkneyle]

Re: LG 42PJ350 Starts, Shuts down, won't restart

You know, those regulators are so cheap I don't think you have anything to lose by swapping it out. I wonder if there might be a dry joint around that reg IC? It certainly seems to be a heat sensitive fault. Maybe in the first instance hit it with a hot iron. While you're at it just heat up any other joints associated with large current carrying components. Let us know the outcome.

[51k.bos]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Which would be easier for a non technician do it yourselfer? Replacing with the parts kit or replacing the faulty board?

[dkneyle]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Well, you'd need reasonable soldering skills and a solder sucker. If you aren't experienced in soldering then you'd likely get yourself into trouble. So if you could pick up a replacement board at a good price then it's a fairly straight forward process to unplug the leads and swap boards over.

[newtothis]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Soldering isn't that hard, As long as you have an iron and some solder its easy enough to swap components out.

*** Totally opposite view to the post above me, My Mrs can swap components in and out... Even fashioned a solder sucker ourselves when I was first learning. I am sure if she can do it with no experience then you can ***

If you want to know how we did a solder sucker... Ever seen those bug catchers.. Its a jar with 2 pipes going into it... One longer than the other inside the jar... Suck one end and aim the other pipe at a bug and it sucks it in. Due to the one pipe being higher than the other in the jar it just traps it. Works the same with solder. Only requires a quick sharp intake of air to suck up solder in a thin pipe... you won't inhale enough to get any fumes near your lungs so don't worry about that

[51k.bos]

Re: LG 42PJ350 Starts, Shuts down, won't restart

I do have experience soldering jewelery, glass and other artsy things but have never done anything like this. I found replacement boards on eBay for not much more than the kit... so I think I'll play it safe and opt for that route. .. Now To make sure I replace the correct board, I should do the freeze test correct?
Now I downloaded the training manual and granted it doesn't all look like Greek to me, but some of it is over my pay grade... Should I test all the boards? I really appreciate your help!

[dkneyle]

Re: LG 42PJ350 Starts, Shuts down, won't restart

The power supply board is the one that the mains lead connects to.

[Mikeyboy2007]

Re: LG 42PJ350 Starts, Shuts down, won't restart

i have LG 42PJ350 with same issue someone has asked me to look at. did we find a repair for this ?

[dkneyle]

Re: LG 42PJ350 Starts, Shuts down, won't restart

Yeah the regulator chip on power supply. Might be as simple as dry joints I suspect on reflection. Hit those solder pads with a hot iron first. Let us know how you go.

[Mikeyboy2007]

Re: LG 42PJ350 Starts, Shuts down, won't restart

where is the regulator chip on the psu ?

[Mikeyboy2007]

Re: LG 42PJ350 Starts, Shuts down, won't restart

also i checked all diodes on board and diode D304 gives 001 reading both ways, is this a bad diode ?

[vinceroger69]

Re: LG 42PJ350 Starts, Shuts down, won't restart

remove or lift one side of the diode and re check.
have you checked all these parts as in a previous post do they check ok
r927 22ohm resistor
r929 22ohm resistor
ic301 3br1565jf regulator
d304 diode

[Mikeyboy2007]

Re: LG 42PJ350 Starts, Shuts down, won't restart

will check those and post back, also can you tell me which is the regulator chip on the psu ?

[vinceroger69]

Re: LG 42PJ350 Starts, Shuts down, won't restart

ic301 i would guess not sure where on your board it is but as a guess it will be on a heat sink if you cant find it maybe look in the training manual in this thread or post a good clear picture of your board.