Panasonic TC50PG15 7 blinks, SC repair?

[johnboy1313]

A friend gave me this set. I just put a $125 A-board in it. I powered it on, the screen primed, there was a small pop, and then 7 blinks. I see four sellers on eBay offering repair for this board TNPA4782 but I'm not gonna drop another $140 into this. Have any of you successfully repaired this board? tw2005, I'm looking your way.

[tom66]

Re: Panasonic TC50PG15 7 blinks, SC repair?

I believe it's similar to G10, tw2005 has done a few.
The thing that worries me, A board can cause SC failure (as it controls the SC) so a bad A board may have killed your SC.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

Well, that sucks. Thanks for the info, I'll look into returning this board.

[tom66]

Re: Panasonic TC50PG15 7 blinks, SC repair?

I wouldn't say it definitely killed it -- in fact I'd say it's unlikely -- but then again getting two separate faults is unlucky and/or improbable.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

Hopefully tw2005 will chime in soon. Thanks for the input Tom.

[tw2005]

Re: Panasonic TC50PG15 7 blinks, SC repair?

Nil info i'm afraid. only done the one version of SC for the G/V 20 series.

Did find a chinese serv tip for the 42G10, may have some clues but for SOS5.

I did throw a few ideas into this post and possibly might be similar cct design.

posts 17 & 18 https://www.badcaps.net/forum/showthread.php?t=27921

good luck

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

I contacted the seller of the board and told them I needed to return it. Their listing said there would be a test performed on any returned boards and a 20% restocking fee if the board was determined to be funtioning correctly. There was no question on their end, just an immediate and full refund. They didn't even respond to my email, just a refund. I'm thinking they questioned the status of the board to begin with, took a gamble, and weren't surprised when the board was faulty. Fortunately, this TV was given to me, so I'm not out anything to sit on it until suitable replacement parts can be scrounged.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

I decided to focus a bit more on this set. I disconnected the SC and powered it on. I got six blinks. No surprise. I reconnected SC and disconnected SU and SD and jumpered SC50. I powered it back on and to my surprise, I got a solid LED and the set powered off with the button. Correct me if I'm wrong, but doesn't this point to a failed buffer and a good SC?

[tom66]

Re: Panasonic TC50PG15 7 blinks, SC repair?

Seems quite likely. You can also do SC50 jumper and individual SU or SD, you should get half a picture which may or may not be distorted.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

I tested the buffers per tw2005's instructions in his TNPA5081 rebuild thread. I see nothing that points to an obviously bad SU or SD.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

Well, something happened. It came on with the SD connected and SC50 jumpered, showed a scrambled picture for a second, then it shut off and flashed 7 blinks. Not with both SD and SU disconnected and SC50 jumpered, it still flashes 7 blinks. Looks like the SC is done now.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

I take it back. I may just order both SU and SD and see what happens.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

So the LED stays lit with SU and SD disconnected and SC50 jumpered. I get seven blinks with either SU or SD connected. I see no shorts on either board. The screen primes, top or bottom, when either board is connected. Do you think I'm just looking at replacing the buffers or do you think there's something else going on here.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

So, turns out I was testing the boards incorrectly (no surprise here). Fortunately, our resident Panny SC expert posted this troubleshooting guide in another post. I just went through it and determined that my SU and SD are both faulty. My SC tests to be OK. I am going to pull the trigger on a set of buffers and see what I get.

[johnboy1313]

Re: Panasonic TC50PG15 7 blinks, SC repair?

I'm thinking I must have a bad panel. I got a new SU and SD board and tested them before I installed them. The TV came on and showed a picture with a few lines across the screen, then shut off and flashed 7 blinks again. With the buffers removed and SC50 jumpered, I still get a solid LED.