Panasonic TC-P65S1 - begins power up, then shuts off

[khnitz]

Make: Panasonic
Model: TC-P65S1
Description: 65" Plasma, Manf. Jan-2010

I picked up this TV to give a go at repairing it, rather than just letting it get thrown out. The TV did not power on anymore. After pressing the power button on the unit, there would be a first relay click, then a second (and the cooling fans would start spinning). A second later there would be another relay click (the fans turn off) and a last click and then the front power LED begins blinking steady (1s on, 3s off). I replaced the stressed large 'lytics on the MULTI and SUS power boards (3X - 350uF 450V, and 3X - 1200uF 220V). The replacement caps are 390uF 450V, and 1200uF 250V - new Nichicon parts rated, like the originals, at 105C.

After replacing those stressed 'lytics, I am still getting the same behavior (power up, then off, and the steady, 1-blink LED). I see no signs that the screen is powering up (I'm more familiar with LCD sets, than plasma, but there's no action on the screen during this power up/down process).

I have the service manual for the unit, and am familiar with electronics repair and troubleshooting. The service manual provides no guidance for a steady 1-blink state...it seems to be the universal "you're scr***d" indicator. The only measurement I've taken so far was to see that (between test points TP5 and TP6 on the SUS power board), the Vsus rail climbs to about 185V before the shut-off.

Any help is appreciated...I'd like to get this running for the kids to enjoy at Christmas.

A little about me, as relates to this forum: I've already repaired a viewsonic 23" LCD monitor, Dell 19" monitor and Element 42" LCD TV by replacing bad electrolytic caps in the power supplies. I've repaired covergence problems on rear-projection TVs by replacing the convergence ICs in the past, too.

[tom66]

Re: Panasonic TC-P65S1 - begins power up, then shuts off

One blink is "No particular check point." Generally, it indicates A/DA board, I think.

BTW, Panasonics rarely have cap issues. They use decent capacitors unlike some other manufacturers.

[khnitz]

Re: Panasonic TC-P65S1 - begins power up, then shuts off

Thanks, Tom. I'm trying to narrow down the issue so that I only have to replace the truly bad board. I'm leaning towards the A-board, at this time, too.

I'll try to post a picture of the venting 'lytics that I replaced. They were obviously bulging. Either way, I'll feel better knowing that they were replaced, once this is up and running again.

[tom66]

Re: Panasonic TC-P65S1 - begins power up, then shuts off

Every time someone mentions they replaced caps on a Panny, I say "they don't fail", they say they were bulged, and I then look at the pics, see they are United Chemicon or Nichicon, and the bulging is very slight, vent not broken, and simply due to how the cap was made.

[khnitz]

Re: Panasonic TC-P65S1 - begins power up, then shuts off

I think these were United Chemicon. They are bulging, though likely not vented. I have seen my fair share of vented caps from working with electronic ballast designs years ago - those were usually field returns of 120V units that were installed on 277V lines :-)

[khnitz]

Re: Panasonic TC-P65S1 - begins power up, then shuts off

After some more information gathering and measuring of outputs from the power supply boards, I'm ording up a replacement A-board and will roll-the-dice with that. Should have further results by week's end.

[khnitz]

FIXED! Panasonic TC-P65S1 "1-blink" error code

This TV is FIXED and ready for the kids to enjoy over the holidays! I replaced the A-board and it is now working. With the new, large electrolytics on the power supply boards, too, this one should hopefully serve my family for a long time to come.

[tom66]

Re: Panasonic TC-P65S1 - begins power up, then shuts off

Fantastic. A board failures seem to kill Panasonics. Not sure why. They are otherwise very well built. Especially when compared with Samsung plasma TVs...