Panasonic TC-P55VT30 7 Blink Troubleshoot log!

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

I will take some voltages tomorrow. I think the panel is fine, not sure why I only see maldischarge on the scrolling bar screen.

If there was a major issue it would have shown its face on the test patterns.

[tw2005]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

I will take some voltages tomorrow. I think the panel is fine, not sure why I only see maldischarge on the scrolling bar screen.

If there was a major issue it would have shown its face on the test patterns.

who knows, i have no answer for it.

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

One thing I will note, cold panel the maldischarge was blue on scrolling bar.

[tw2005]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

One thing I will note, cold panel the maldischarge was blue on scrolling bar.

weird, maybe the voltage is out a whisker?

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Seems it likes the VSUS voltage on high. After leaving it off for awhile and coming back the maldischarge seems almost none existent on scrolling bar.

I will get some voltages and confirm, so spec for this SC is 204-209? I cannot find a service guide for this panel.

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

I just Want to make sure this TV is going to last because it's going to replace the fancy LED Samsung upstairs.

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Gonna let it run the retail loop on the Disney wow disc, see if anything changes after a hour or so.

[tw2005]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Seems it likes the VSUS voltage on high. After leaving it off for awhile and coming back the maldischarge seems almost none existent on scrolling bar.

I will get some voltages and confirm, so spec for this SC is 204-209? I cannot find a service guide for this panel.

There's a service manual for TC-P55VT30 and in the schematic of the SC at the SC2 connector you will find what i have quoted

Lo 204
Hi 209

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Thanks tw2005 for the help!

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

This is what I got for voltages, I don't think the VSUS test is meant for voltage testing as I was getting very low readings as soon as I switched to the full white test patterns the voltage was super high after adjusting the VSUS pot on the VSUS TEST menu.




VSUS test HIGH VIA SERVICE MENU OPTION.

VSUS FROM BOTH P11 ect 201.7
SC TPVAD 184.9
SC TPVSUS 201.7

SS TPVe 135.4
SS TPVSUS 201.7

VSUS TEST OPTIONS IN SERVICE MENU.

Capped POT at 206.8 VSUS HIGH
Capped POT at 201.7 VSUS LOW

Test pattern white (capped pot 215.1) adjusted to 210.5 VSUS on high
TPVE 135.5
TPVAD 184.9 (spec says 200? See photo attachment) adjusting the VDA pot made no change.

[tom66]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Vda != Vad. Make sure to set Vda to it's nominal rating (usually 55V.) Are you saying your Vsus is only ~201V? That sounds very low for a modern Panny panel. Can you try adjusting it to 210V?

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Hello Tom66!

Vsus is sitting stable at 205.5 with Vsus setting on low via the service menu (spec is 204).

I had it at 210.5 and there was no change to the Scrolling bar issue on any other picture setting besides VIVID. VIVID setting with scrolling bar there is no maldischarge at all.

For the VAD, I only see one Test Point for it on the SC board TPVAD. If I put my + probe on the arrow pointed part of the resistor I get 40.5v, if I put my + probe on the arrow pointed part and my - probe on the other side of the resistor I get 184.9.

I tried adjusting the VAD pot on the PS and I didnt see any change in voltage on the SC board on the TPVAD test point.

Is there another test point I am missing? Is there a VAD Test Point on the SMPS?

Thanks!

Oh and one thing to add as well, Firmware is up to date too.

[tom66]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

There is no Vad pot on the power board. You are adjusting Vda. Be very careful as high Vda can damage the plasma panel!

Vad is generated on the SC board and on modern Panasonic plasmas is not adjustable. You may still have a fault on your SC if Vad is a little low.

Out of interest, is a full white pattern pinking out or just the scrolling bar?

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

There is no Vad pot on the power board. You are adjusting Vda. Be very careful as high Vda can damage the plasma panel!

Vad is generated on the SC board and on modern Panasonic plasmas is not adjustable. You may still have a fault on your SC if Vad is a little low.

Out of interest, is a full white pattern pinking out or just the scrolling bar?

Gotcha, is there a Voltage TP for VDA so I can see what its showing? I put the pot back were it was I had it marked.

As far as picture quality goes, the full white test screen shows no missfire at all, in fact nothing shows any issues outside of the top of the scrolling bar with minimal pink/redish sometimes blue pixel storm. I can try to take a video but each pass of the white scroll bar the pixel storm/maldischarge goes away to where it only shows up in the top right corner or top left corner (kinda random).

I did however seem some strange stuff with the TV in Standard mode (in the service menu) and I dont know if CATS is on by default with Standard when in sesrvice mode but the picture was really grainy and darkish and the test patterns were doing strange stuff. When I am in normal TV operation mode outside of the Service menu I turned CATS off and the picture was fine.

I will post photos of that here in a few.


But as far as the TV goes I calibrated it to C-Nets post 222 firmware settings on Custom picture setting 100 IRE and it looked freaking fantastic.

I will ping ModusLink and see what they say, I am confused about the Voltage for TPVAD the manual say's 200 + 5V for VAD.

Again thank you for your help Tom66!

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

This is what I am seeing with TV set to Standard in Servie Menu Test Pattern mode.

The patterns eventually look normal in about 2 seconds so I am not sure what to think of this, this issue is ONLY applies for Standard Picture setting, no other picture setting is affected like this.

I don't know if CATS is on by default for Standard picture mode in the SM but CATS was on in normal operation mode and I turned it off, the picture in normal operation mode with CATS on was horrible, dim and grainy and when I turned it off the picture quality improved a lot and the grainy look was gone too.


Anyway!

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

/bump!

anyone have any idea's what else to look for?

ModUSlink told me my buffers are shot, I am not 100% on board with that assessment.

[tom66]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Very much doubt bad buffers would cause this. My guess is some fault with the initialisation ramps/pulse on the board perhaps damaged when original parts failed. Any access to a scope to check the output waveform? Is SS Ve voltage OK?

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

SS Voltage seems to be stable, Ve was 135.5.

I still have that 60hz ATTEN scope.

[tom66]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Want to try sticking the ATTEN on the output of the SC and see what you get? Might give some clues as to the fault.

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Want to try sticking the ATTEN on the output of the SC and see what you get? Might give some clues as to the fault.

Sure, can do that when I get home this evening. I didn't see a TP for Wave output on the SC when I was looking but I could have missed it!