Panasonic TH-58PZ800U major problems

[kmenc13]

I've been struggling for 6 months or so with a dead Panasonic 58" TH-58PZ800U. Tried another forum for a while and received a recommendation to come here and see if anyone had some insight. Here's the sordid tale:

In December it started putting out a 7 blink LED error. I unplugged it and let it sit 24 hours, after which it worked fine. A month later, the screen shut off and put out a 2 blink code (15v SOS). For this model, that indicated the D board (main logic board) as the check point. I ordered a replacement and installed it. At startup it gave a 3-blink error (3.3V SOS), indicating the A Board(Main input/tuner). I sent the A board off for repair & return since I couldn't find a replacement. The shop tested it and said it was fine and sent it back. I put it back in along with the original D board. 2 blinks again.

Since the power supply boards are typical culprits, I ordered a replacement P board. No change. On the chance the replacement was defective I had a local shop do a diagnostic on the whole set. They said both old and new P boards were fine, but there was a short in the SC (Y-main) and SS boards. OK, fine, that makes sense considering the earlier 7 blinks. They wanted over $600 for the repair but I knew I could get those boards for about $80, so I ordered them and installed. Now I get 5 blinks (5V SOS - D board), and if I hold down the power button it becomes 10 blinks (Sub 5V SOS, Main 3.3V SOS, DTV 5V SOS Tuner Power SOS - A-Board).

I have dumped a large amount of money into what I hoped would be a quick DIY fix and am still baffled. The only visible possibility I see is a break in the plastic cover of the A11 connection going into the A-Board.

I'm willing to go through a last-ditch attempt to find the problem by checking test point voltages with a multimeter, but would need some guidance by someone more experienced with this sort of thing. Any other insight or suggestions are welcome. Thanks.

[tom66]

Re: Panasonic TH-58PZ800U major problems

So does the TV still give 2 blinks?
What tools do you have - a digital multimeter?

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Right now, with the original P, A & D boards and the replacement SC and SS boards installed, I get 5 blinks, and if I hold down the power button it changes to 10 blinks. If I put all of the original boards back in, it's 2 blinks.

I can get my hands on a digital multimeter, yes.

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Still looking to get some guidance on trying to go through testing with a multimeter to try and figure out what's going on with this thing, if anyone can help. Anyone have access to the testing procedures for this model?

[Moreno83]

Re: Panasonic TH-58PZ800U major problems

Did you fix this yet?

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Not fixed yet. I've replaced several boards with no success, but have no way to know if the replacements are faulty or if the problem lies elsewhere. Still looking for information and procedures on how to test them myself to try and locate the problem.

[Moreno83]

Re: Panasonic TH-58PZ800U major problems

hm ok , i had a panasonic vier a with 5 blinks and i fixed it with a different main board. Could be eeprom?

[tw2005]

Re: Panasonic TH-58PZ800U major problems

Quoted from AVS

Still struggling with a Panasonic TH-58PZ800U I'm desperate to fix. The saga to date:

Several months ago, this plasma failed mid-viewing and put out a 2-blink error. I checked the manual, which indicated the D-Board. I ordered a replacement and when I installed it, started getting 3 blinks, indicating the A-Board (inputs). I couldn't find a replacement for that so I sent it off to ModusLink for repair/return. They said the A-Board was fine and sent it back. I re-installed it - 3 blinks. I reinstalled the original D-Board as well and was back to 2 blinks. Since the power supplies are problematic on Panasonics, I took a chance on replacing the 2-piece P board (I also tried chilling the MC301 and MC201 with no effect). No change after swapping P-Boards. Frustrated, I took the whole thing to a local repair shop for testing in case I was getting dud replacement parts. They said both the original and new P boards were fine, but there was a short in the SC and SS boards. I replaced those and now get 5 blinks. And when I hold down the power button, it goes to 10 blinks. Also, if I disconnect the cables to the SC board and turn it on, it gives out 10 blinks.

The only possible visible issue I can see is the connector at the end of a wire cluster leading into the A-Board at the A-11 connection is cracked.

Any suggestions would be appreciated as well as any guidance on checking voltages to try and pin down the source of the problem.

I forget what info you have but getting 10 blinks with the SC2 and SC20 removed sounds wrong. Normally I'd expect 6 blink.

Everytime you change a board your result seems to change too and looks like you've changed everyboard except the C buffers but being all used boards that in itself is an unknown variable.

have you tried disconnecting A6,A7 (or P6,P7)

Does the TV turn on by itself with
Power LED = Off
SC LED= On
SS LED = ON

I'm hoping the 50' model guide is of some help.

I'm thinking you follow the 10 blink after power on flowchart, you've already isolated the SC so next step is the SS board(pg 28)

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Quoted from AVS




I forget what info you have but getting 10 blinks with the SC2 and SC20 removed sounds wrong. Normally I'd expect 6 blink.

Everytime you change a board your result seems to change too and looks like you've changed everyboard except the C buffers but being all used boards that in itself is an unknown variable.

have you tried disconnecting A6,A7 (or P6,P7)

Does the TV turn on by itself with
Power LED = Off
SC LED= On
SS LED = ON

I'm hoping the 50' model guide is of some help.

I'm thinking you follow the 10 blink after power on flowchart, you've already isolated the SC so next step is the SS board(pg 28)

Disconnecting A6,A7 or P6, P7 results in no power whatsoever.

I hope I'm not misunderstanding your LED question, but with everything connected, and plugging in, I hear the initial clicks, but there's no LED indicator until I give the front power button a quick push (5 blinks) or a long hold (10 blinks). I'm probably an idiot but I can't find an SC LED or SS LED.

I'll try following that flowchart as you suggested.


Some further background on this set if it might be helpful (or maybe just confuse things further): Prior to this failure, there were 2 occasions when the set failed with a 7 blink LED (Driver SOS2, SC floating voltage area, check points SU, SD, SC) , a couple of years ago and about a month prior to the final failure. Unplugging the set and allowing to sit for 24 hrs resolved those issues (at least temporarily). However, after this final failure, when I opened the back, the fans were choked with dust. I have since cleaned everything out, but seems to me this indicates that something overheated.

[tw2005]

Re: Panasonic TH-58PZ800U major problems

Disconnecting A6,A7 or P6, P7 results in no power whatsoever.

I hope I'm not misunderstanding your LED question, but with everything connected, and plugging in, I hear the initial clicks, but there's no LED indicator until I give the front power button a quick push (5 blinks) or a long hold (10 blinks). I'm probably an idiot but I can't find an SC LED or SS LED.

I'll try following that flowchart as you suggested.


Some further background on this set if it might be helpful (or maybe just confuse things further): Prior to this failure, there were 2 occasions when the set failed with a 7 blink LED (Driver SOS2, SC floating voltage area, check points SU, SD, SC) , a couple of years ago and about a month prior to the final failure. Unplugging the set and allowing to sit for 24 hrs resolved those issues (at least temporarily). However, after this final failure, when I opened the back, the fans were choked with dust. I have since cleaned everything out, but seems to me this indicates that something overheated.

the idea of disconnecting a6,a7 is to force on the PSU and sustain boards, driving the panel on. try a5,a6,a7, should go on and full white screen. The front panel LED will not be on because it's disconnected, I forget if you also have to hit the power button.

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

the idea of disconnecting a6,a7 is to force on the PSU and sustain boards, driving the panel on. try a5,a6,a7, should go on and full white screen. The front panel LED will not be on because it's disconnected, I forget if you also have to hit the power button.

Disconnected a5,a6,a7 heard a couple of clicks in back but no screen. Tried using front power button but still no screen.

[tom66]

Re: Panasonic TH-58PZ800U major problems

Could you try with your original SC/SS boards installed? I'm not convinced they are OK.

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Could you try with your original SC/SS boards installed? I'm not convinced they are OK.

Well, disturbingly,it looks like something additional must have happened during all of the card swapping.

With all of the original boards returned, I'm still getting 5 blinks when plugging in and turning on with the front power button (as opposed to the original 2 blinks when the fault originally occured).

Disconnecting only SC2 and SC20 gives me 10 blinks.

Disconnecting only A6 & A7 - clicks at plug-in but no screen, with or without pushing the front power button

Disconnecting A5,A6,A7 - clicks at plug-in but no screen, with or without pushing the front power button

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Well, I finally got around to getting a digital multimeter, figuring out how to use it, and started going though the technical guide flowchart - then about 5 steps in I realized that manual doesn't appear to correlate to the 58" model (the flowchart calls for testing certain connectors that don't exist on this model i.e. SC46). So now I'm on the hunt for a technical manual specifically for the TH-58PZ800U before I can really go any further.

[tom66]

Re: Panasonic TH-58PZ800U major problems

3rd result
http://www.toms-service-manuals.com/...&Search=Submit

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Thanks. I already have that Service Manual, but it doesn't include any troubleshooting flowcharts like the Technical Guide.

[tw2005]

Re: Panasonic TH-58PZ800U major problems

Well, I finally got around to getting a digital multimeter, figuring out how to use it, and started going though the technical guide flowchart - then about 5 steps in I realized that manual doesn't appear to correlate to the 58" model (the flowchart calls for testing certain connectors that don't exist on this model i.e. SC46). So now I'm on the hunt for a technical manual specifically for the TH-58PZ800U before I can really go any further.

SC46 is the centre connector that goes to the SD board (normally)

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Ugh. You're right. I'm an idiot. It wasn't labeled on the schematic I was looking at but I can see it on the board. Maybe this will work after all. Thanks.

[kmenc13]

Re: Panasonic TH-58PZ800U major problems

Ok, Interesting so far. Since, when I turn the set on I get 5 blinks, but when I hold down the power button I get 10, I followed both the 5 blink flowchart and the 10 blinks after pressing power flowchart. According to the 5 blink chart, I should replace the SD board since no short appears at P25 after disconnecting SC46. According to the 10 blink after power chart, I should replace the P board since voltage is missing at P12 - although I'm not sure about that result. The previous step asks if the LED stays on after power, but the power button is completely unresponsive after disconnecting SS11 SS33 & SS34 and putting the jumper on P25. I read that as a "no."

I take that back on the 10 blink chart. On re-checking, there are no voltages missing, which would mean to replace the A board (the one I already had tested by ModusLink and was sent back as ok).

[tw2005]

Re: Panasonic TH-58PZ800U major problems

does it give you a sd/su buffer bypass procedure to run the sc without buffers connected?

If it's a buffer board then isolating it should mean the TV will turn on?