Pink sparklies and voltage - Panasonic P42UT30B

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

Use the highest voltage range for your meter (usually 500, 600 or 1000V DC). Make sure to use DC, not AC mode.

Vsus can be measured at TPVSUS on the power board.

The SN board (large green board on the left hand side when looking from the back) has the Vad and Vscn voltages.

You test them on the points TPVAD, TPVSCAN with red probe on those points and black on the chassis.

The Vda voltage should be available on a small connector on the power supply, or thereabouts, maybe on a point marked TPVAD. Generally in the 55 to 65V range (often 58V on modern Panasonic PDP).

Be very careful not to slip the probes or touch high voltage parts. It may help to have the ground lead put in a screw hole (I find the stand bracket part works quite well).

After much scouring, this is the only TPVSUS point I've found. Upon finding it though I noticed those brown scorch(?) marks on those solders...



And on further inspection they're all over the left board and look more like rust

[tom66]

Re: Pink sparklies and voltage - Panasonic P42UT30B

Those marks are just dried flux and aren't a fault.

[Moreno83]

Re: Pink sparklies and voltage - Panasonic P42UT30B

As tom says , just flux.

Please follow my steps and post the results or take pictures!

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

Use the highest voltage range for your meter (usually 500, 600 or 1000V DC). Make sure to use DC, not AC mode.

Vsus can be measured at TPVSUS on the power board.

The SN board (large green board on the left hand side when looking from the back) has the Vad and Vscn voltages.

You test them on the points TPVAD, TPVSCAN with red probe on those points and black on the chassis.

The Vda voltage should be available on a small connector on the power supply, or thereabouts, maybe on a point marked TPVAD. Generally in the 55 to 65V range (often 58V on modern Panasonic PDP).

Be very careful not to slip the probes or touch high voltage parts. It may help to have the ground lead put in a screw hole (I find the stand bracket part works quite well).

TPVSUS (Measured on right hand board): 217V
TPVSUS (measured on left hand board): 219V
TPVAD 33.9.
TPVSCAN I can't find nor see in the manual.
Can't find TPVAD (or vda?) on the power board.

[tom66]

Re: Pink sparklies and voltage - Panasonic P42UT30B

It's TPVDA on the power board...maybe TPVDATA or VDATA.

Your Vsus looks too high, can you try adjusting the potentiometer so it is around the 209V range?

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

It's TPVDA on the power board...maybe TPVDATA or VDATA.

Your Vsus looks too high, can you try adjusting the potentiometer so it is around the 209V range?

Both of the potentiometers? I'm assuming one is for left and one for right as I have 2 test points?

[tom66]

Re: Pink sparklies and voltage - Panasonic P42UT30B

This TV has only one Vsus voltage, only the larger panels (60"+) have separate Vsus. You are measuring the same voltage on two separate places (SN and SS board).

Adjust only the highest potentiometer on the power board.

Note ideally you would have a static image up while testing, as Vsus may vary by a couple of volts with the image.

Do not adjust the lower potentiometer, it is the Vda adjustment and it is possible (though unlikely) to cause damage to the plasma panel by increasing Vda too high.

[Moreno83]

Re: Pink sparklies and voltage - Panasonic P42UT30B

219V is way to high and thats why you got sparkles.

Start with 209V and see what happens.

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

219V is way to high and thats why you got sparkles.

Start with 209V and see what happens.

VSUS at 209v tested on a static screen doesn't eliminate the sparklies, though it does improve them.

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

It's TPVDA on the power board...maybe TPVDATA or VDATA.

Your Vsus looks too high, can you try adjusting the potentiometer so it is around the 209V range?

The closest I've found is VDATA

[tom66]

Re: Pink sparklies and voltage - Panasonic P42UT30B

That's the ticket, test that pin (1) there.

**Under no circumstances disconnect that connector or adjust it while power is live as it is possible to kill the plasma panel doing that.**

[Moreno83]

Re: Pink sparklies and voltage - Panasonic P42UT30B

Dont forget that you now might see plasma dithering and not sparkles.

Voltage on 209V and look at the screen from a 2 meter distance. You still see sparkles?

Please take a picture of the screen displaying a normal tv picture.

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

True , but luckily the voltage on this set won't go lower then 199 and higher then +/-213V. ( If vsus is 209v )
Vsus is normally written on the panel sticker.......

I have seen plasma tv's that had sparkles because of the arching problem....got worse and worse and then shut down with the 7 blink error. I also saw some threads where people said the image on the tv got worse and shut down with a big bang.

Its good to check the screws anyway!

Think I forgot to say I took each screw off (except for the ones on the LED circuitry) and checked for any scoring. I only found one screw that looked a bit off and replaced it (had an identical one lying around). It didn't make any difference to anything.

[Moreno83]

Re: Pink sparklies and voltage - Panasonic P42UT30B

Ok but please take a picture of the tv from 2 meter distance. Maybe your now seeing plasma dithering which is normal.

Also the arching is UNDER the sc board , im sure the pads are black.

https://3.bp.blogspot.com/-XeSHIPRVb...70401_0001.jpg

This is what is happening under your sc board.

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

Ok but please take a picture of the tv from 2 meter distance. Maybe your now seeing plasma dithering which is normal.

Also the arching is UNDER the sc board , im sure the pads are black.

https://3.bp.blogspot.com/-XeSHIPRVb...70401_0001.jpg

This is what is happening under your sc board.

Will do when I'm home from work.

[tom66]

Re: Pink sparklies and voltage - Panasonic P42UT30B

When removing the SN board, keep the orange ribbons that go to the panel attached, and very carefully flip it off the side of the TV. Best to have the TV lying face down when doing this.
Reason is they're a pain to get back in once removed, took me quite a while on my ST50B and if you don't need to remove them, don't!

[Moreno83]

Re: Pink sparklies and voltage - Panasonic P42UT30B

So did you reset the tv to its factory defaults also? Picture settings can cause sparkles , definately when set on 219V

It's best to get all values back to its default , hardware and software!

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

So did you reset the tv to its factory defaults also? Picture settings can cause sparkles , definately when set on 219V

It's best to get all values back to its default , hardware and software!

Yeah I did that before starting anything else.

[jonnyapps]

Re: Pink sparklies and voltage - Panasonic P42UT30B

That's the ticket, test that pin (1) there.

**Under no circumstances disconnect that connector or adjust it while power is live as it is possible to kill the plasma panel doing that.**

57.6v on that.

Pink static definitely still present. Have viewed from normal viewing distance which is 2m give or take. Doesn't resolve in a photo but then that's to be expected.

Current pink static:



A bit more info, that may or may not help anything:

• This static is constantly moving like snow on a TV.
• If I look at the TV through the corner of my eye I can see the panel flickering with the refresh rate (60hz).
• There's a buzzing that comes and goes depending on what's on screen. Silent as I type this, buzzes when I tab to imgur.com (black background).

[Moreno83]

Re: Pink sparklies and voltage - Panasonic P42UT30B

Oke , first things first because i got the idea your accidentally skipping some possible solutions. Did you tighten ALL the screws on every board including C boards?

Could you please do the following?
Turn tv off and lay the tv on a soft cloth/table etc with the screen facing down.
Remove the power and sc20 cable from the scboard and remove all the screws from the board.

Flip the board gently to the left and see if you notice any black marks on the sc board and chassis holes. If so , then take a solder iron and resolder the pads. Only need little solder.
If you don't have a solder iron then scrape the black resideu off the board and chassis.
Reinstall the board and screws and tighten them. Does it change anything?

If not , try to alter the Vsus voltage a little. Place the tv on its stand and use a small screw driver to alter the vsus voltage with 2 / 3 v and see if it gets better. Maybe use a mirror so you can see what you are doing. If there is almost no difference then there are a few options left. ( Don't forget the meter so you can read the voltage , 2v can do ALOT so be careful ).

Possible solutions:

1) Try to set V-sus to HIGH in service menu
2) Replace the mainboard , maybe the GPU is bad causing maldischarge.
3) Worst case scenario is that the panel is failing.

The buzzing sound that you are hearing is the plasma panel , usually on bright pictures.

Let us know what you find!