Panasonic TC-50PU54 8 blinks picture flashes then dead

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

I am still thinking A board. Do you have any more thoughts?

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

I'm thinking A board, but I'm only about 80% sure.

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

thanks for all the help Tom. I ordered the A board for $18.99 on ebay. Hopefully that is what I need. I am at the limit of my knowledge, so it is worth the risk. I will notify this post when I get the board if it works or not.

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

$19 is damn cheap for an A board!

[tw2005]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

Hard to believe but probably this guy, has some real bargains at times. Must depend on the old supply and demand.

Must have a few to clear and they'd be new sets transit damage too.

http://www.ebay.com/itm/PANASONIC-TC...item27d633e3fb

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

Got the A board in today and still the same problem. the screen lights up and then goes into shut down with 8 blinks. Does anyone have any thoughts as to what I could look for at this point?

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

I don't really know, can you try with your old SS board in case new one is bad? Very hard to tell without a scope to be sure.

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

Yeah, I tried the new A board with the original SS board. Same thing. Going off the service manual you posted earlier, I have a bad panel. I trouble shot the SD/SU board by following what was in that manual and it seems fine. This all was a result of a power surge. I guess it could have knocked the panel out. I was just hoping for something easier. I will just part out the rest of the boards.

[tw2005]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

How long does the panel light up for? Is it a normal display or is it simply a quick flash and shutdown?

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

I really doubt a power surge can kill a panel. Bad electrode structure, due to dirt or debris, or broken ffc maybe, but not a power surge.

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

The pic flashes on for less than a second and then goes into 8 flash mode. I didn't think a surge could cause a panel to go bad either, but I'm out of answers. I am still open to suggestions though.

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

You don't have a scope?

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

No, I don't have a scope.

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

According to the manual, the C3 board could also cause an 8 blink. It doesn't really say how to troubleshoot that board though.

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

Check the +3.3V and Vda on it. Vda should be around 55V.

[tw2005]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

slide for what it's worth

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

I have 3.3 v on all three C boards when the Tv comes on and then they all go to 0v when it goes into shutdown and starts the 8 flashes. Where is the Vda?

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

Do you see the little green SMD resistors? Vda can be tested on either end of those.

[aasnowskate]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

Thanks, I have 58 VDC when the tv starts up and it drops to 39 VDC when it goes into shutdown. That is on the C3 board

[tom66]

Re: Panasonic TC-50PU54 8 blinks picture flashes then dead

Seems like there is no short there.
8 blink panel failure is only caused by:
- Shorted 3.3V/Vda on C board
- Open SS FFC

Neither of which you have determined to be bad.

I really doubt it is the panel but I don't know what else to suggest, it is very hard to check these things without having a scope.