Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Found something interesting not sure if this will help or not but on pin 1 and 5 of ic773 is shorted both ways. Could someone verify if this is correct? Thanks and hope this helps add into this tnpa4844 board debunking

Seriously, I'd start a separate post. Following 2 separate people fault finding a board could get messy.

I'm going to assume you do not have a copy of the service manual? Check out the schematic which explains all. 1 & 5 are connected.

measure pins 3 & 5 though. Check Q701,702 for short and R707 burnt or open cct.

All these models have the same SC as yours. TC-54PS14, TC-P54G10 if you can't get the exact manual.

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

With IC564 removed (waiting for new parts) TP82 to gnd is about 4.4K.

Across C563 measures approx. 153K after it settles.

TNPA5081

TP82 1.3Kohms, red to gnd, blk to TP82

C563, equivalent location on my TNPA5081 C561 5.56Kohms. Try both polarities, a lot of times the cct reacted in one direction but gave an instant steady reading in the other. The latter is what I recorded for comparison.

[smartjohn]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Found something interesting not sure if this will help or not but on pin 1 and 5 of ic773 is shorted both ways. Could someone verify if this is correct? Thanks and hope this helps add into this tnpa4844 board debunking

Asuming freakaftr8, you're still watching this thread, my SC is also same, TNPA4844. I will check ic773 and report back.

I would start with Isolating the SU/SD Boards using the "2009 Technical Guide", http://www.scribd.com/doc/80432198/P...echnical-Guide.

Go to Slide #51 and Slide #63. YOU MUST JUMPER SC50 (picture on slide#65- Use a single aligator clip or smaller hard drive jumper)
to get this to work. Do the steps on #63, DO NOT LET THE SET RUN over 30 SECONDS. If the set comes up and runs, YOUR SC board is OK, replace or repair your SU/SD boards. I found them for $5 ea on ebay. If you still get 7 blinks, we are both on the same cruise line (boat!), I'll paddle faster! (probably a bad SC component(s))

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Hi smartjohn. Yep I think we're both on the carnival triumph here. Lol. Yes I used the service manual to isolate the boards. And with the su and sd pulled from the sc and sc50 jumpered still shutdown with sos7.

[smartjohn]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

General question: What should I be measuring 5V_F_A (B) with respect to? VFG? I replaced IC564 and the current draw from my 5V test supply dropped to about 200ma, down from over 400ma.

So I decided to pop the SC board back in and try running in isolation (NO SU/SD, and SC50 jumpered). Same damn 7 blinks! VSUS pops up for 2 seconds as before then cuts out.

I stuck my meter on the 5V_F_B output of the regulator IC725, fired it up again and I was getting -160V to chassis gnd?? so i guessed I must not be ckecking relative to the correct gnd?

[smartjohn]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Hi smartjohn. Yep I think we're both on the carnival triumph here. Lol. Yes I used the service manual to isolate the boards. And with the su and sd pulled from the sc and sc50 jumpered still shutdown with sos7.

Lol, yeah I hope our cruise will end better than that one, eventually!

Tw2005 has fixed at least 2 of his SC's so we know it can be done. I think I am going back to the print (pg 73 - 76) and start checking all chips vcc to input / output resistance. I may hang a current limited 15V supply on IC791 pin 4/5 DC-DC converter and see if I get more hot potatoes somewhere.

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Ok what am I doing wrong? Pin 11 and 12 of ic791 are supposed to be 16 and 32v. I'm getting an output of -141 after 2 seconds goes up to -175vdc! Are these output pins? The schematic shows so..

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

What do you get 11,12 with respect to pins 1or 2 (gnd). -175V sounds like the VAD voltage level. I'm having trouble working out the cct too?

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

What do you get 11,12 with respect to pins 1or 2 (gnd). -175V sounds like the VAD voltage level. I'm having trouble working out the cct too?

Getting the same reading grounded to pins 1 and 2 as well.

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

I have no answers, sorry.

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Well I also tapped in a 9v battery resistor limited to 5v to pin 11 and 12 of ic791. Nothing got warm at all. Used freeze spray as well. I did notice a current drop on pin11 but it might be the d583 indicator led causing the load drop. I don't mean to sound dumb but do you suppose it could be a malfunctioning dc dc converter ic791? I noticed other pics on the Internet of the converter covered in orange instead of black.

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

My sc does not have that setup but my other TV does. Same gen as yours but the HD model 42". I never did figure out what exactly failed however I do know none of the FETS had shorted and VAD was low below the minmum threshold which tripped SOS7. VSCN also bad.

There was no response from the trimmer adjustment, just stayed the same. I ended up disabling the SOS cct and got the TV to stay on but a little flickery. But that was after I managed to fluke the TV on by repeatedly switching it on & off.

It almost sounds like your board has not shorted out. Any FETS blown?

I guess you could hook your probes up to the test points and see if that gives any clues but bypassing protection has it's risks of more damage??

https://www.badcaps.net/forum/showthread.php?t=21255

This shows the voltages affected on mine, but I never worked it out and it seemed tto hard to track down panasonic components so i gave up and tossed it out.

wish i still had it now as a new challenge since I got lucky with my 2 TNPA5081 boards.

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

No no fets blown. I like your thinking of disabling sos7. How would you go about it? Disconnecting pin 21 from the sc20? I removed c566 and still getting 3.5 at pin21 sos7.

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

No no fets blown. I like your thinking of disabling sos7. How would you go about it? Disconnecting pin 21 from the sc20? I removed c566 and still getting 3.5 at pin21 sos7.

Nevermind. I cut the trace to pin 21 on sc20. Fired right up! Perfect picture! Tpvad at -175vdc and tpvsus at 30! I don't get it but...

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Smartjohn. Give it a shot if all else fails and you remove the shorts from the ic's. it sounds like your path is a different one since you have fets shorted. I can tell you thou that with sc2 removed pin 11 of dc regulator was outputting 9v. That's low but pin 12 put out 25v

Tw2005 thank you for the advise. Guess I got lucky. After all the tnpa4844 is unobtainable and if it failed I would prob need an a board as well but, hell it worked.

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Nevermind. I cut the trace to pin 21 on sc20. Fired right up! Perfect picture! Tpvad at -175vdc and tpvsus at 30! I don't get it but...

TPVSUS 30?? What point was that measured at? On the SS board?
I doubt it would even fire the panel.
You're not mixing this up with TPVscn on the SC board??

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

I'd still be fault finding it to see why it tripped, check all the levels. The onboard LED on the SC lights up? I assume it has one. FGirst time I did a bypass I cut and removed parts, second time on a different board I earthed out the sos line. Might have been SOS6 , forget it's in a thread somewhere.

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Lol yea I measured from the tpvsus resistor. Yes the inboard led lights up. Checked all voltages and they ate all in spec within 2 volts except to ad where it's 5 volts low.

Watching it now and absolutely flawless picture. No flickering maldischarge of any sorts at all. Fires on the first startup too. What I did is cut the trace to pin 21 of the sc20 so the voltage high cannot reach the a board and all is well

[freakaftr8]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

Are one of those poteometers on the sc board related to vad adjustments? If so the vad being out of spec 5v triggered the SOS. That's a small window compared to thee sc boards panasonic manufactures in other sets. I would say leaky resistors are culprit causing the circuit to drop off spec to trigger the SOS.

[tw2005]

Re: Panasonic TC-P42G10 Plasma - Seven red blinks Dead No power

so can you list the values of the TP or what TPVAD is exactly. The adjustment points are in the table.