Panasonic TH-50PZ800U - 10 Blinks

[difluoroethane]

Hey guys, I have the Panasonic model listed in the thread title, built in June 2008, that has worked flawlessly since then. I normally leave it on (hooked up to a computer than runs ElectricSheep to prevent any ghosting when not being used for something else) but it was turned off by a power outage a few days ago. When I tried to turn it back on I got the 10 blinks

Ok, so I unplugged it and let it sit a while and after plugging it back in, it will turn on no problem and will stay on with no issues. If I turn it off and then try to turn it back on, back to 10 blinks unless I unplug it and let it sit for a while (~5 minutes or so). I imagine it would probably stay on indefinitely if I left it on, but I would hate for it to go out completely so would like to troubleshoot.

I was able to find a few things before I came across the forum here that I've already tried. If I unplug A6 and A7 and try powering it on, I get a dark grey light screen. If I do the same thing with A5 also unplugged I get a bright white screen. I read that unplugging those connectors are supposed to assist in tracking down which board might be bad and show what's supposed to still be good. I have to leave the TV unplugged between attempts though, otherwise it will not try to power on. From what I gather, the SC and SS boards are probably ok and I'm probably looking at a failure of the A board, although the fact that it still will not power on with the A board unplugged unless I let it sit between attempts makes me wonder if maybe one of the power boards could be bad? Maybe heat is causing something to short out?

This thing is a bit more complex that what I'm used to troubleshooting, so if anyone has any ideas they want to throw my way, I'm all ears. I'm about to go check to see if I'm getting 15vdc on A6 pin 7,8,9 after trying to power back on and can take pictures if they are needed. I'll update with my findings.

Thanks!

Randy

[tw2005]

Re: Panasonic TH-50PZ800U - 10 Blinks

Hey guys, I have the Panasonic model listed in the thread title, built in June 2008, that has worked flawlessly since then. I normally leave it on (hooked up to a computer than runs ElectricSheep to prevent any ghosting when not being used for something else) but it was turned off by a power outage a few days ago. When I tried to turn it back on I got the 10 blinks

Ok, so I unplugged it and let it sit a while and after plugging it back in, it will turn on no problem and will stay on with no issues. If I turn it off and then try to turn it back on, back to 10 blinks unless I unplug it and let it sit for a while (~5 minutes or so). I imagine it would probably stay on indefinitely if I left it on, but I would hate for it to go out completely so would like to troubleshoot.

I was able to find a few things before I came across the forum here that I've already tried. If I unplug A6 and A7 and try powering it on, I get a dark grey light screen. If I do the same thing with A5 also unplugged I get a bright white screen. I read that unplugging those connectors are supposed to assist in tracking down which board might be bad and show what's supposed to still be good. I have to leave the TV unplugged between attempts though, otherwise it will not try to power on. From what I gather, the SC and SS boards are probably ok and I'm probably looking at a failure of the A board, although the fact that it still will not power on with the A board unplugged unless I let it sit between attempts makes me wonder if maybe one of the power boards could be bad? Maybe heat is causing something to short out?

This thing is a bit more complex that what I'm used to troubleshooting, so if anyone has any ideas they want to throw my way, I'm all ears. I'm about to go check to see if I'm getting 15vdc on A6 pin 7,8,9 after trying to power back on and can take pictures if they are needed. I'll update with my findings.

Thanks!

Randy

If you still had intermittent issues powering up with the A board isolated I'd be leaning towards the PSU.

Fairly common issue with this series.

Quite often it's a tiny ceramic capacitor on either the MC201 or MC301 daughter board modules located on the PSU.

search TEA1611T or mc201, mc301 within this forum should get you some hits.

Also you tube video on repair

https://www.youtube.com/watch?v=LjpGKaBt8hg

I forget which causes which off hand but I had intermittent turn on 2 blink on a 46" and all I did was replace the cap, some have replaced the IC as well.

[difluoroethane]

Re: Panasonic TH-50PZ800U - 10 Blinks

Ok, so I went to test the TV and found that after leaving it unplugged for a few days it doesn't want to come on anymore. Plugging it in I hear the relays click on and then back off almost immediately. I do have +5v(STB) and +3.3v(STB) (tested from A1 pin 4 on the A board), I do not have FSTB+15V. From P(AC) I get +5vDC out at D551 which from following the wiring diagrams is where the +5v(STB) comes from and it goes to IC4000 which gives the +3.3v(STB). One thing I did find confusing (and I'm assuming is a typo, although it is repeated elsewhere in the diagrams) is that pin 10 on connector P12 on P(Main) says it should be +12v, but I only get +5v. According to the diagrams it should actually be +5v, not 12 as it is tied to the +5v(STB) circuit. I also get +5v on pin 5 of P7 and pin 9 of P25 so that leads me to believe that MC701 and MC552 are working to some extent as +5v(STB) wouldn't make it to P7 and P25 without MC552 being switched on by MC701. With MC552 switched on, K601 and K602 should also both be switched on, but that does not seem to be the case as I can hear them flipping on and then back off and I'm not getting FSTB+15V.

As it's late and I'm tired, I think I'm done for the evening, but at this point I am leaning towards the P(Main) board being the issue seeing as I'm not getting FSTB+15V. If my logic is flawed, or there is something else I should be checking, please let me know!

:edit:

Just saw what you posted tw2005. MC201 and MC301 are the Main and VSUS power control modules. That means it is probably MC301 since that would control the FSTB+15V circuit. Guessing it's probably a filter cap that shorted, huh? Had a very similar issue happen to my old Dell m1530 a while back. Anyway, thanks for the input. I'll check it more tomorrow.

[tw2005]

Re: Panasonic TH-50PZ800U - 10 Blinks

1uf 50v ceramic , watch the video

[martino]

Re: Panasonic TH-50PZ800U - 10 Blinks

Do yourself a favor and replace both caps. One on MC201,one on MC 301.
If your good at soldering,you can do it with the powerboard in place.Just solder a 1uF 50 volt electrolytic cap on to the legs of the IC,first glue body of cap to IC,then bend legs onto pin 11 and pin 13(pin11 is the negative lead).check you don't bridge 2 legs with solder..
Like tw2005 said,watch the video.......I never had to replace the Ic as in the video,just the caps.
And your right,it's MC301 for 10 blinks,MC201 for 2 blinks,change them both so you don't have to do it again soon.

[difluoroethane]

Re: Panasonic TH-50PZ800U - 10 Blinks

Hey guys, anything wrong with getting this 50V 1mfd tantalum capacitor that is available at the Fry's near where I live? Or would you recommend I order a ceramic cap online instead? If the tantalum one is fine I could have it back up tomorrow instead of having to wait for shipping.

Also, thanks for the video link tw2005! I appreciate the assistance both of you have provided!

[martino]

Re: Panasonic TH-50PZ800U - 10 Blinks

I'd say it would work,but not 100% sure. Never tried one of those,only the electrolytic ones..

[martino]

Re: Panasonic TH-50PZ800U - 10 Blinks

guess this makes it a yes for that cap

https://www.badcaps.net/forum/attach...5&d=1337394168

[difluoroethane]

Re: Panasonic TH-50PZ800U - 10 Blinks

Cool. I didn't figure it would hurt anything, but I don't think I've ever had a need for a tantalum cap, so I wasn't sure if they had a special use. Did a little research, and it seems they do have their special uses, but it also seems that it will work fine for what I'm trying to do, and with the picture you linked, it seems like someone else has done the same.

The only problem is Fry's only had 1 50v 1mfd cap in stock :/ I guess that will allow me to get me TV running again, but I'll probably tear it apart again to replace the other one once I can get another cap.

[difluoroethane]

Re: Panasonic TH-50PZ800U - 10 Blinks

Hey guys, just wanted to let you know that I was able to get another cap and replaced the caps on both mc201 and 301. Tv works great now. Thanks for your help!

[martino]

Re: Panasonic TH-50PZ800U - 10 Blinks

Awesome! Wasn't too hard to solder?
Thx for the update on the fix

[nwcs]

Re: Panasonic TH-50PZ800U - 10 Blinks

I fixed this one but now I get a horizontal line thru the bottom of the picture. The customer had originally changed the buffer boards. I repaired the P board to get a picture. I checked all of the ribbon cables to the buffer boards and they seem ok. Could anyone tell me if this looks like a bad plasma panel or something else.

[nwcs]

Re: Panasonic TH-50PZ800U - 10 Blinks

Sorry, I forgot for the picture of the line.

[ReeceyBurger123]

Re: Panasonic TH-50PZ800U - 10 Blinks

Redo the ribbons again and make sure there is no bent pins in the buffer card, customers have a habit of fucking things up when they attempt to repair.

[nwcs]

Re: Panasonic TH-50PZ800U - 10 Blinks

Thanks, I will try that. I just took it off the bench for a different tv.

[nwcs]

Re: Panasonic TH-50PZ800U - 10 Blinks

Ended up being a bad panel. one of the flat ribbon cables to the panel is damaged.

[ReeceyBurger123]

Re: Panasonic TH-50PZ800U - 10 Blinks

Ahh no shame, maybe just keep it as it is just try to ignore the line ?

[nwcs]

Re: Panasonic TH-50PZ800U - 10 Blinks

I think I am going to pull the parts and sell them. At least I know they are working.

[ReeceyBurger123]

Re: Panasonic TH-50PZ800U - 10 Blinks

Yeah shame really these are nice panels, certain the customer would have done that when bodging the buffers.

[Alastair E]

Re: Panasonic TH-50PZ800U - 10 Blinks

Damned 'have-a-go heros' kill more good stuff than the faults themselves!