LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

[caprat]

I recently obtained a LG 50PC1DR. I hoped that the three bubbled capacitors I found on the power supply were the only problem. I replaced those today and the TV still has the same problem: The TV makes a clicking sound, flickers at a 2-3x per second pace. The picture seems fine when it flickers on and the sound is just fine.

After I replaced the capacitors I noticed the clicking is coming straight from the Y-Sustain and clicks with the flickering. I took tom66's advice and bridged the optocouplers and it did nothing to help. The y-sustain still clicks and the screen still flickers.

Any advice beyond "replace the Y-Sustain board"? Thanks guys.

[mstats1]

Re: LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

I just got this same model from a friend who didn't want it. The tv was having the same issue of flickering with no picture but audio was working. I also heard the ticking from the Y Sus. I just took it all apart and on the back of the Y Sus board there is some burns.
Anyone know if this one part (PMI?) can be replaced or does the whole board need to be replaced?

[tom66]

Re: LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

IPM can be replaced. You might hear clicking from just one IPM? If so, you need to replace it. Tricky job, not impossible, but you need good soldering skills.

[mstats1]

Re: LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

Any idea where to purchase new IPMs?
Should I replace both while I'm at it?
I'm not that practiced at soldering. What do I need to be careful of?

[tom66]

Re: LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

Any idea where to purchase new IPMs?
Should I replace both while I'm at it?
I'm not that practiced at soldering. What do I need to be careful of?

You will need to remove the heatsink covering the IPM; there should be a part # on it. The IPM is the large device under the large metal heatsink. In particular, with soldering, you will need a very high power soldering iron, probably 50..60W, as the board is essentially a large heatsink.

[cliff_hootarski]

Re: LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

I've got two of these boards right now that do that exact same thing.
I have previously sent another board to Coppell's TV repair (see Ebay) and had them repair that board ($135). I plan on trying to fix the two boards I have now.
I ordered a desoldering machine from Amazon which should arrive tomorrow.
The replacement IPM's can be bought on Ebay. I plan on just replacing the IPM that is making the ticking noise(upper one).

[scokljat]

Re: LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

I just got this same model from a friend who didn't want it. The tv was having the same issue of flickering with no picture but audio was working. I also heard the ticking from the Y Sus. I just took it all apart and on the back of the Y Sus board there is some burns.
Anyone know if this one part (PMI?) can be replaced or does the whole board need to be replaced?

Well, this "burns" I think are actually remains of a lousy solder work when someone replaced that IPM module previously. There might be a bad solder joint.

I would first clean all that soldering paste with isopropyl alcohol, than suck some excessive solder with wick or pump, and finally neatly resolder all IPM legs with new solder.

If it does not help, replace IPM. Maybe if one is cooler then another, I would replace cooler one first. Leave the set to work and heat up for 10-20 minutes and then switch it off and touch and compare heat of all IPM heatsinks on Y/Z boards. Ones that are lot cooler than others are defective.

Cheers,

Suad

[mstats1]

Re: LG 50PC1DR Y-Sustain Clicking - Screen Flickering..

Suad - I came to same conclusion that someone else had replaced the chip as well. The soldering was so different from everything else on the board. I only have a 25W iron that I don't think will clean all this up though. This is the same chip that was making the ticking sound when the TV was on so maybe the replacement was bad.
I had called a TV repair shop in my town to see how much they would charge to take off the chip and install a new one for me. But they wouldn't quote me a price without looking at it first and charging me $70 at the same time.
Not sure how much money I want to drop on this TV, but I think I'll go out and get a 50W iron and take off the offending chip.