HP Plasma CPTOH-0603- Picture goes blank after a few minutes

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Anyone?

[freakaftr8]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Whats vs reading when picture goes out? Had one of these lg made sets. It turned out.to me an intermittent short in the ysus ipm module. It was in such a way that it kep t the vs line alive. Get a fan and point it on ysus ipm and power up. How long does is stay in now?

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

It reads 86v when the picture goes out. I tried the fan method you wrote and pointing it at the right lower corner of the power supply board (as in capkid's picture in previous post) keeps the tv on for quite some time. I tried it on the ysus, but it had no effect.

Without the fan pointed at this spot on the PSB, it takes around 5 min for it to go out from a cold start, and about 1-2 min for the picture to go out when already warm.

With the fan pointed at this area, I can keep the tv going for over 15 min.

I tried cold spray in this area but it didn't do anything. So is this definite proof I have a bad power supply board? Can I find out what component on this board is failing?

Thanks

[tom66]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Does it slowly drop or go suddenly to 86V?

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

It drops suddenly to 86V

[freakaftr8]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Siunds like a sudden load down of the vs circuit. Leave it on like this and feel the ysus and zsus ipm. which ones cool?

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

I checked and there is a slight temperature difference on the upper cooling fin on the y-sus when there is a picture and when there isn't. All of the cooling fins on both boards feel warm overall. The fins are all about 42C, but I don't have the right thermometer to measure the differences.

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

any ideas?

[capkid]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

It seems like the PSU is the issue. Something appears to be failing on the primary side of the PSU (the side to which you pointed the fan) that is bringing down the VS on the secondary side. Primary and secondary are separated by a bold black line.

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Is it possible or worthwhile for me to find and replace the failing component(s) on the PSU to save money? How hard can this be?
Thanks

[capkid]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

I guess it depends on your definition of "worthwhile". Obviously, you'll have to spend some time testing the board, and it may not be easy to find the failing components. Here's a used board from a reputable company that comes with a 6-month warranty: http://tristatemodule.com/t-Search.aspx?q=3501Q00200A.

eBay: http://www.ebay.com/sch/i.html?_saca...00200A&_sop=15

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Thanks, I'll try looking at the prices for replacement boards for now, and if I find a good deal, I'll buy the board.

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

So I bought a new power board, and I connected it to the tv. The tv ran fine for about 30 minutes. I then heard a pop like something blew, and now there is no picture. All the tv does is the power board seems to cycle on and off, and I can hear a buzzing on the z-sus. Plugging the new power board or the old one makes no difference.

Here are the voltages:
VS: 5.3V peak, cycles from zero and ramps up to 5.3 before dropping to 0v.
VA: 0.5V peak
VY: 0.19V
ZBIAS: 0.13V
+5V: 4.9V

Does anyone have any idea what I can do or what's wrong now?
There are multiple LEDs on some of the control boards that turn on/off or blink that could be used to troubleshoot the tv, but I don't know how to decode them.

Can anyone help me please?

Thanks

[freakaftr8]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

You may have an IPM module going badd inn the Zsus or Ysus boards. This is the IC under the big heat syncs on the side boards. Most likely one of the ER IPM modules get too hot, andd make a momenntary internal short. Associated with heat as these IPM modules work under extreme conditions. Leave the set on wjhen the screen goes out and feel the heat syncs, all fourr of them. One will probably start to cool off over the course of 20 minutes or so with the screen not operating, but the tv is still on. That could be your culprit.

[freakaftr8]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

that pop you just heard is a sure tale sign one of those IPM modules just went bad if you hear the zsus fire up between power cycles but ysus is quiet, ysus is and was your problem.
Rebuild or.replace.

Be warned thou. Your zsus could go too. If it wasnt damaged by the ysus. Kind of like replacing tires. Thet.wear out.

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

There is no picture at all now after the pop. Is there anything I can try measuring with a multimeter to find out which board is bad? How can I tell that the zsus got taken out/ or will go out soon? I didn't see anything that looks visibly blown.

Thanks

[freakaftr8]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Check fuses on both Z and you. are any open?

[mh321]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

The 2 fuses on ysus are still good. I can't find any fuse on zsus.

[freakaftr8]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

oh yeah that's right my bad the Zsus fuse is on the ysus. Unplug power connection to Zsus. does the TV state powered up now even though you're not going to have a picture

[selldoor]

Re: HP Plasma CPTOH-0603- Picture goes blank after a few minutes

Just to be sure -My understanding is, you should not be plugging/unplugging while the set is ON

see here
https://www.badcaps.net/forum/showthread.php?t=18542