Panasonic TX-P42G10B 5 blinks

[tom66]

I decided to get a G10... saw one cheap near me and snapped it up. In great condition. I won't break the panel on this!!

TX-P42G10B
Has a TNPA4844 SC board

Seeing 5 blinks I was suspecting panel. Thought it was worth a risk anyway. Turns out SC board is dead short zero ohms across Vsus. I presume this triggers the 5 blinks fault. Unplugging SC gives expected 7 blinks.

Buffer boards test OK no shorts across FGND to VSCAN or to panel ribbons.

Found a good collection of IGBTs dead short. Q604 is OK so it's a Vsus short versus other faults which cause 7 blinks. I guess next step is to replace IGBTs and possibly the driver IC?

Any good sources for IGBTs - utsource I presume?

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

Tests: 0.0 ohm at Vsus

IGBTs G-C-E short:
Q621/Q623, Q422/Q423/Q424 (G-C/G-E leaky - 120 ohms), Q661

IGBTs only G-C short (G-C/G-E open):
Q402/Q403/Q404

FET shorted D-S, leaky D-G:
Q660

[tw2005]

Re: Panasonic TX-P42G10B 5 blinks

All chinese to me Tom

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

IC16771 = no shorts
IC16464 = untested, but if Vreg & driver OK should be fine
IC16465 = as above
IC16773 = no shorts Vcc/GND/out any way
Q16701 = no shorts, seems OK
Q16702 = no shorts, seems OK
D16865 = need to pull IGBTs to be sure if good/bad

Rough translation seems to indicate that if the FETs are bad above components should be tested and replaced.
I know you have experience with logic buffer ICs being bad, did you usually find them shorted? I'm getting kohm+ for all of them. Same for the Vregs.

I think I'm going to pull all the FETs/IGBTs, jumper SC50 & test with a scope for drive waveforms. See what it looks like then see if I need to do any of the small logic. Even the gate resistors for the IGBTs test OK.

[tw2005]

Re: Panasonic TX-P42G10B 5 blinks

IC16771 = no shorts
IC16464 = untested, but if Vreg & driver OK should be fine
IC16465 = as above
IC16773 = no shorts Vcc/GND/out any way
Q16701 = no shorts, seems OK
Q16702 = no shorts, seems OK
D16865 = need to pull IGBTs to be sure if good/bad

Rough translation seems to indicate that if the FETs are bad above components should be tested and replaced.
I know you have experience with logic buffer ICs being bad, did you usually find them shorted? I'm getting kohm+ for all of them. Same for the Vregs.

I think I'm going to pull all the FETs/IGBTs, jumper SC50 & test with a scope for drive waveforms. See what it looks like then see if I need to do any of the small logic. Even the gate resistors for the IGBTs test OK.

If you're talking about the octal buffers from sc20 I've had one short but any one of the buffer ccts within could be damage which i don't think you could prove with a meter. Worst case there I think it may simply not work and throw a sos7 which i've had one do.

I'd be more focussed on those schmitt inverters and to be honest easy and cheap to get especially if you use a texas instruments chip which they have a direct replacement for. If they're bad I'd expect transistors to short out again.

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

I think the best way is to see if the IGBT gate waveforms are OK. Then I can go ahead with replacing the driver ICs & logic if necessary.

Which Schmitt inverters -- you talking about the ones near the IGBT drivers? For those I can check input & output and see how it looks.

Got any good sources for the required IGBTs/FETs? UTSOURCE I presume?

[tw2005]

Re: Panasonic TX-P42G10B 5 blinks

I think the best way is to see if the IGBT gate waveforms are OK. Then I can go ahead with replacing the driver ICs & logic if necessary.

Which Schmitt inverters -- you talking about the ones near the IGBT drivers? For those I can check input & output and see how it looks.

Got any good sources for the required IGBTs/FETs? UTSOURCE I presume?

UTSOURCE is all I have used with the 5081 boards and had no issues. Prices have dropped quite a bit not sure about the ones on your board but given the time it takes for these to arrive I'd get extras in case first attempt fails.

EIther that or see if there are any kits but usually more expensive. iC773,464,465

mentioned in the guide Q16701、Q16702、D16865、
IC16771、IC16464、IC16465、IC16773

Marked HA if they're the same as the 5081

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

Thanks to tw2005's keen eye, an SC board was spotted on eBay Poland. £33 later, the TV is working great!

[tw2005]

Re: Panasonic TX-P42G10B 5 blinks

Thanks to tw2005's keen eye, an SC board was spotted on eBay Poland. £33 later, the TV is working great!

Hell, that was a coincidence, I was just digging this up to see where you got with the repair when I remembered the tip.

Sweet. glad it worked out, bonus - you still have a SC repair project

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

17,007 hours and 3,000 power cycles - panel is absolutely PERFECT with no burn in at all! And it's SO BRIGHT!!! Brighter than my Kuro, PZ80 & D450-3D.

[tw2005]

Re: Panasonic TX-P42G10B 5 blinks

17,007 hours and 3,000 power cycles - panel is absolutely PERFECT with no burn in at all! And it's SO BRIGHT!!! Brighter than my Kuro, PZ80 & D450-3D.

Pretty sure this has been asked before but what is the highest hrs you've seen on a panasonic?

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

14,500 hours on a PZ80, this is a new record. I have never seen burn in on a Panasonic plasma panel, having done 8 now. Yet I've seen plenty of LG & Samsung panels with burn in and less than 10,000 hours.

Man, if it were only Panny making plasmas, it'd have a far better rep as a technology!

[tw2005]

Re: Panasonic TX-P42G10B 5 blinks

Well, I hope mine keeps running well beyond. they're great panels. I'm going to keep my spare 42X20 and 46PZ now that there's no more Plasmas built by panasonic.

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

Yep, with Sammy leaving the biz this year, and LG likely to follow suit soon, I might have to stop fixing plasmas - no good if I can't sell them!

[tw2005]

Re: Panasonic TX-P42G10B 5 blinks

Yep, with Sammy leaving the biz this year, and LG likely to follow suit soon, I might have to stop fixing plasmas - no good if I can't sell them!

Really, yeah, LCD posts are higher than plasma and over here nationwide on Ebay, very poor for picking up decent stuff but see a few PZ series popup still.

[tom66]

Re: Panasonic TX-P42G10B 5 blinks

Eh, this one was VERY cheap on eBay so I nabbed it quick!