Panasonic TH-50PZ80U 7 Blinks

[kevinm34232]

Owner said tv just started blinking LED 7 times. When I got it home I noticed screen was cracked. Not sure if I missed it when I bought it, or it cracked in transit, I did have to lay if down on its back.

But still 7 blinks when plugged in. Wondered if 7 blinks was due to broken screen.

Removed all ribbons to panel and connections to lower buffer. Still 7 blinks.

Removed connections to SC board, TV stays on.

Im thinking if screen was good before, SC board was bad...

But if screen was broken before, maybe took out SC or buffer? How can I check if it's the SC or the buffer boards?

I did try disconnecting buffer SU and SD while SC board still connected with same 7 blinks.

Thanks!

[tom66]

Re: Panasonic TH-50PZ80U 7 Blinks

Cracked screen can lead to shorted panel electrodes, so yeah, can cause 7 blinks by killing SU/SD.

To isolate SU/SD on this set you need to perform the procedure outlined here (pg. 63):



otherwise it'll still throw 7 blinks (because buffer not detected.)

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

I think this would blink at you if the SU and SD were disconnected even if the screen was intact. 7 blinks is generally related to buffer failure, whether it was the original fault or whether the owner cracked the screen while on, or powered on afterwards. Test buffers for short between each output pin and the ground (floating ground) of the buffer, that will often reveal a short-circuit, see if it corresponds to the cracked area of the screen.

[kevinm34232]

Re: Panasonic TH-50PZ80U 7 Blinks

Awesome thanks.

Jumpered VF_GND to L801 and TV stays on with SC board still connected. So problem is bad buffer boards then right?

[kevinm34232]

Re: Panasonic TH-50PZ80U 7 Blinks

Clydeuk you're right found short on on lower SD board second connector down.

Can I plug in connector to upper buffer while jumper is in place to see if that board is good?

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

Not sure I would risk though I don't think it will harm it, but with the jumper in place the SOS detect isn't going to protect anything and I don't want to advise you to do it and you wind up killing the SC board, maybe Tom know's more. Is the shorted ic in the cracked area of the screen?

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

Buffer failure was very common on these, every one I had only needed one either SU or SD. I'm trying to work out a chicken and egg situation here by finding whether your buffer short is close to the cracked area. SC failure was also common, they issued a firmware update to use following repair. Not your problem here though yours is fine.

[capkid]

Re: Panasonic TH-50PZ80U 7 Blinks

That's too bad, Kevin. It's got a pretty nice picture when it works.

[kevinm34232]

Re: Panasonic TH-50PZ80U 7 Blinks

Could this have been caused by laying it down on its back with the stand still on in the car? It didn't get banged around and I never had it happen, although this is a heavier TV. Last time I tried keeping them standing upright the TV's fell over and broke some screens so I try not to do it if possible.

Oh, Sorry Clydeuk, well the crack is pretty much a snake that goes from the bottom left to the top right of the screen so can't say for sure.

[capkid]

Re: Panasonic TH-50PZ80U 7 Blinks

Could this have been caused by laying it down on its back with the stand still on in the car? It didn't get banged around and I never had it happen, although this is a heavier TV. Last time I tried keeping them standing upright the TV's fell over and broke some screens so I try not to do it if possible.

Oh, Sorry Clydeuk, well the crack is pretty much a snake that goes from the bottom left to the top right of the screen so can't say for sure.

If I have to transport these on their backs, which is becoming more frequent with the larger TV's I pick up, I always cushion my SUV's cargo area with a couple blankets, old towels, or an old pillow. I ALWAYS take the stands off, too.

Edit: If you don't already, take a flashlight with you to thoroughly check out the screen.

Second edit: If I'm picking up a smaller TV in my car, I take off the stand and lay the TV against the seat with the screen facing away from the seat.

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

I don't think so but who knows? They are fairly robust though. They are a cracking set when they work these, sourcing a panel may be difficult though if not prohibitively expensive. They were NLA from manufacturer when I used to service them.

[kevinm34232]

Re: Panasonic TH-50PZ80U 7 Blinks

Yes I have a TC-P50G10 also that I just fixed and was very impressed by the picture.. I really am considering keeping it that one. Was looking foward to getting this one fixed too.

Oh I did reconnect upper buffer and remove the ribbon between the 2 buffers and TV did come on and stay on, nothing smoked, so Im gonna assume the SU is OK..

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

Well Kevin the snake probably doesn't say much, a tiny crack in one corner could easily spread across like that when handling. You can test the upper buffer same as the lower. If there's no obvious short assume it's ok, if it's not ok the SOS will prevent the thing starting when it's hooked in to a good panel. If you were planning on selling the board though I wouldn't until you can confirm it's condition.

[capkid]

Re: Panasonic TH-50PZ80U 7 Blinks

I have a TH-50PZ80U and its cousin the TH-C50FD18 (same TVs, but the 50PZ80U has a shiny bezel). I was going to sell the TH-C50F18, but I'm thinking about going "MTV Cribs" status and putting it in my office

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

I'd choose a panny over any other when it came to plasma, and build quality is superb as well.

[kevinm34232]

Re: Panasonic TH-50PZ80U 7 Blinks

Yes at this point Im going to have to sell the other boards to make back the $, and I don't want to sell it if Im not sure so I will hang on to that one for now..

And of course the stand for the TH-50PZ80U is not compatible with TC-P50G10 that I need a stand for

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

I need a stand for a TX-P50U20B 3D plasma, that's not happening yet either but I'm keeping my eyes peeled. You should get a good return for the boards you can salvage.

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

got that wrong its the VT20B i need a stand for

[kevinm34232]

Re: Panasonic TH-50PZ80U 7 Blinks

I ordered the one for the TC-P50G10 already because I only had less than $40 in the TV. I paid $60 plus shipping for it. They are just not readily available..

[Clydeuk]

Re: Panasonic TH-50PZ80U 7 Blinks

I bought a new stand around December for a L55DT50B I got for absolute peanuts
(£25). It cost me nothing to fix the TV (one salvaged SM capacitor) the stand cost almost £100 and had to be bought as 3 pieces direct from Panasonic. It was a new set though and was retailing then for £1500 so I think I did ok there. It lives in my lounge