Panasonic TC-P55VT30 7 Blink Troubleshoot log!

[tom66]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

You would use the screw links going to the buffer boards SU/SD. You may have to solder a wire to a board to do this test. Or you may be able to use a lead on a connected component (IIRC, at least a few FETs are connected to the VFG out...)

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

You would use the screw links going to the buffer boards SU/SD. You may have to solder a wire to a board to do this test. Or you may be able to use a lead on a connected component (IIRC, at least a few FETs are connected to the VFG out...)

If I have to solider a wire on the SC I might hold off until ModusLink gets back to me about returning the SC board for them to go over. I am waiting to hear back. I can try to put the Scope Probe on the HV bolt and see what I get.

I dont want them to have a way out if they see anything out of sorts.

DAMN out of all the panels I have done its got to be the one I want to keep that is having small issues

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

ModusLink just reached out to me and they want me to send the SD/SU and SC boards in for testing.

So I am going do that and report back on what they find, I am sure the buffers are fine. I dont know if the SS board would do this or not but TPVe voltage was to spec so I am confused, I have never seen this sort of issue.

Thanks again Tom66 and TW2005 for your input!

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Before I pulled SD/SU/SC I did the SC50 isolation test and all the voltages outside of TPVAD was the same.

TPVAD jumped up to 52.7v but with both probes on the TPVAD resistor the voltage was 189.6.

So it seems it's possible a buffer IC was damaged when the original SC failure happened since TPVAD voltage did go up with SD/SU was taken out of circuit.

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

So I just got this from ModusLink. I am not convinced its a bad panel at all.

Hello Jeremy,
The second tracking number is for your SC board. They tested your buffers and they were no fault found and so was the SC so you may have a bad panel. You only was charged 1 bench fee of $35.00 for the testing of the boards. Thank you

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Only two other possibilities are, the SS (not SC) board is going out or the main board is going out too.

I would totally be on board with this "Bad Panel" synopsis if the panel outside of the Scrolling Bar was showing this maldischarge issue, it is not doing that at all, the picture looks fantastic.

I will get the boards back in and run it like it is till it dies.

[tom66]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

It's not the panel. I just can't see it causing that fault.

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Same here, even the voltages on the SS board were to spec.

[Terryfictv]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Also I didn't take any voltage readings because there wasn't any sticker voltages to verify against so I've no idea what they're supposed to be.

When I repair sustain boards, I like to know what temperature the heat sinks are at... so I measure and monitor with an infrared thermometer ( Cen-Tech).
While precise voltage settings are desirable, knowing the temperature is a little too high can help finish a repair that might otherwise end up as a re-call.
Just a thought.....

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

The panel ran very cool compared to my 60PV450 LG. I left it on for 6 hours after I installed the freshly rebuilt SC board running the retailer loop on the Disney wow disc and the temp never felt any any abnormal heat.

I do have a laser temp gun I can try that.

I am guessing it's a glitch with the scrolling bar, as none of the other white test pattens show any anomalies.

[tom66]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

Do you get a similar pattern trying to scroll say a white window across a black screen on a Windows PC? When I was tweaking my Kuro I hit zero black level and had all sorts of weird effects with moving objects. Static objects were fine but anything moving had a pink tint as it seems the green/blue pixels are much harder to discharge on 9G panels.

[Shinju]

Re: Panasonic TC-P55VT30 7 Blink Troubleshoot log!

All of the other scrolling test patterns are perfect, when playing movies the picture is perfect, playing fast paced video games the picture is perfect.

Heh I wi try to see if I can capture what I am seeing with the scrolling bar.