Panasonic TH-50PZ85UA


	FORUM HOME	SEARCH POSTS	WHO'S ONLINE	LOG IN	RULES F.A.Q.

TV Forums: TV Equipment: Plasma TV Forum:
Panasonic TH-50PZ85UA

Print Thread

bonsaitree
New User

Nov 21, 2010, 8:51 PM

Post #1 of 14 (5149 views)
Shortcut

Panasonic TH-50PZ85UA	Can't Post

I bought one of these almost 2 years ago when CC was going out of business. Worked great until I started using an HDMI cable from the cable box to the TV. It burned out the power supply shortly after the warranty period and I had that fixed at a local repair shop. Panasonic helped out and ponied up some cash to fix my set. However 4 months after that problem was fixed it came back! I found a service manual online and figured I'd try to tackle the problem myself. Power LED blinks 10 times so I checked the service manual. sub 5v sos, main 3.3v sos, DTV 9V sos, Tuner Power SOS. It says the check point is the A board. I found an A board cheap on Discount Merchant and put it in. Same symptoms same problem. 10 blinks, tv wont turn on. So I think that it has to be a problem somewhere in the power board, and it gradually got worse over time which would lead me to believe that its a bad capacitor somewhere in the TV. Problem is I can't find a 5V, 3.3V, or a 9V circuit anywhere in the power supply schematics. And half of my capacitors don't seem to charge when I put a MM on them. I have serious doubts that half of the capacitors on the power board are bad, but I'm not sure what to do at this point. Any help would be appreciated!

darstr
User

Nov 22, 2010, 10:32 PM

Post #2 of 14 (5142 views)
Shortcut

Re: [bonsaitree] Panasonic TH-50PZ85UA [In reply to]	Can't Post

Disconnect all of the cable from the power supply and then check your resistance on the vs line to chassi ground and let me know if you have a short or not

bonsaitree
New User

Nov 23, 2010, 5:00 AM

Post #3 of 14 (5136 views)
Shortcut

Re: [darstr] Panasonic TH-50PZ85UA [In reply to]	Can't Post

Do you mean the VSus voltage? I can't for the life of me find a VS voltage on either the auxilary AC board, or the Main Power board.

darstr
User

Nov 24, 2010, 1:22 PM

Post #4 of 14 (5126 views)
Shortcut

Re: [bonsaitree] Panasonic TH-50PZ85UA [In reply to]	Can't Post

Yes your VSUS. It is coming out on both sides of power supply. P11 and P2

bonsaitree
New User

Nov 25, 2010, 1:31 AM

Post #5 of 14 (5119 views)
Shortcut

Re: [darstr] Panasonic TH-50PZ85UA [In reply to]	Can't Post

It would appear that everything is fine. If I check both pins of both of those plugs I get a ~0 reading (>4 ohms) on one pin and on the other pin I get a quick drop and then a climb to large resistance numbers quick. I believe its the white wire that gives me the large resistance and the blue and gray wires give me the zero readings.

darstr
User

Nov 26, 2010, 1:25 PM

Post #6 of 14 (5106 views)
Shortcut

Re: [bonsaitree] Panasonic TH-50PZ85UA [In reply to]	Can't Post

OK thats good. Now do the same check on the sc board pin 1 and the ss board pin 1. Resistance should be in the mega ohms also.

RyanMoroz
New User

Nov 28, 2010, 7:00 AM

Post #7 of 14 (5097 views)
Shortcut

Re: [darstr] Panasonic TH-50PZ85UA [In reply to]	Can't Post

He is right I have has tons of Panasonics over the years and all as to my experience. 10 blinks could be almost ANYTHING.

Most of the time is the Ysus or Y-Buffer. also known as SS and SC. Also I have had 2 cases now where if you use the SD Card slot that 2 of the pins could become conected or twisted and this will actually cause the TV to act up like this as well.

bonsaitree
New User

Nov 29, 2010, 5:08 AM

Post #8 of 14 (5092 views)
Shortcut

Re: [darstr] Panasonic TH-50PZ85UA [In reply to]	Can't Post

Checking the same plugs on the SC and SS boards without anything actually plugged in, both boards give me ~0 on one leg and the other leg gives me a high resistance though the SC seemed to top out at ~200,000 ohms and the SS board seemed to top out at 20,000 ohms. That could just be my old analog MM so I'll check them again tomorrow with a DMM. Unless Pin 1 refers to a different pin than the one used to connect the board to the power supply, those are the numbers. <br>

EDIT: Checked it again today with a DMM and both numbers register at about 3 mega ohms, so I guess my analog just needs a new battery.

(This post was edited by bonsaitree on Dec 1, 2010, 1:42 AM)

darstr
User

Dec 2, 2010, 10:42 PM

Post #9 of 14 (5068 views)
Shortcut

Re: [bonsaitree] Panasonic TH-50PZ85UA [In reply to]	Can't Post

OK. 3 Mega ohms is fine. Now what I would like you to do is disconnect the power supply from the SS and the SC board only. Plug in the set and get your meter ready, because you wont have but a sec or two. Turn the set on and measure the DC voltage at Pin 1 on the SC side of the power supply. Set will shut down. Unplug it and wait for a couple of minutes, then plug it back in , power it up and measure DC voltage at Pin 1 on the SC side of the board. Before the set shuts down, do you start to get a reading on either side?

bonsaitree
New User

Dec 3, 2010, 4:21 AM

Post #10 of 14 (5055 views)
Shortcut

Re: [darstr] Panasonic TH-50PZ85UA [In reply to]	Can't Post

Tried that:

If I unplug just the P2 and P11 plugs then plug things in the light blinks 10 times, wont let me do anything with the power button except reset and then it just starts blinking again.

If I unplug all of the connections between the SS, SC and power boards I dont get a ten blink code but I also cant do anything with the power button.

I unplugged the aux power board from the Main power board and took VDC readings between the pins on those plugs if you want that info. I also verified again that 120 ac is coming in correctly before and after the filter. I'll update with those readings in a bit since I left them downstairs.

P53 plug had 27v one time only 20 the next
P55 plug gave me a couple values depending on the pins 24 24 28 5 and 3 volts
The bottom plug didn't give me anything in vdc

(This post was edited by bonsaitree on Dec 3, 2010, 4:31 AM)

darstr
User

Dec 3, 2010, 1:33 PM

Post #11 of 14 (5049 views)
Shortcut

Re: [bonsaitree] Panasonic TH-50PZ85UA [In reply to]	Can't Post

Like I said. You only get like a second to try to take a reading. If the set starts blinking when you first plug it in, you didn't let the board discharge long enough. You can help it out by holding in the power button while it is unplugged for about thirty seconds or so. When you plug it back in, get your meter on your test point and then hit the power button. You will only get a secong to get the reading. If VS doesn't attempt to climb, then I would asume you have a main board problem, power supply would be secong guess, but we will get in to that later.

bonsaitree
New User

Dec 3, 2010, 2:45 PM

Post #12 of 14 (5047 views)
Shortcut

Re: [darstr] Panasonic TH-50PZ85UA [In reply to]	Can't Post

I believed you about the short amount of time. I had my gf trying to hit the button while I measured the voltage. Do I need to unplug both plugs from the SC (i think) board or just the P11 plug?

The set was unplugged for at least a day before I plugged it in and it goes right to blinking ten times. I do notice that the 5V relay on the main board seems to click twice, almost like its clicking on and then off again. I've tried holding the power button down to help clear capacitors, but if being unplugged for a day doesn't clear them...

darstr
User

Dec 3, 2010, 4:21 PM

Post #13 of 14 (5046 views)
Shortcut

Re: [bonsaitree] Panasonic TH-50PZ85UA [In reply to]	Can't Post

Thats fine. I just had to make sure. I would think it safe to say that your main board is probably at fault here. Especialy since the blinks never changed to a 7 from a 10 when you isolated the power supply.

bonsaitree
New User

Mar 4, 2011, 4:09 AM

Post #14 of 14 (4886 views)
Shortcut

Re: [darstr] Panasonic TH-50PZ85UA [In reply to]	Can't Post

I finally got a "new" power supply board for this thing. I plugged it in and screwed everything down. Plug the TV in and after I tried to turn it on I get two blinks now. Manual says 15V source and that the check point is the D board? Seriously how do I check the D board with it behind another and inaccessible. Any ideas guys?

Print Thread

Search for (options)

- Page loaded in: 0.10 s on (CGI/1.1)