Panasonic TX-P42ST31B 7blinks

[sienoki]

Re: Panasonic TX-P42ST31B 7blinks

I hope you will receive good items. The 30F131 and RJP30H2A are almost all fake.

If you can wash off the logo + name with alcohol/aceton or its fading out then you probably have fakes.

Ive rubbed them hard with IPA n logo fine..Ive installed the 2 R6015ANX n fuse in PSU n now have 230v then ramps down to 216v then slowly decreases..so PSU now good..

Ive got a bulb tester with croc clips attached n a 150w bulb..do i have to cut into vsus cable half way n run in series or just clip onto white connector on SN board..thx

[sienoki]

Re: Panasonic TX-P42ST31B 7blinks

Ive rubbed them hard with IPA n logo fine..Ive installed the 2 R6015ANX n fuse in PSU n now have 230v then ramps down to 216v then slowly decreases..so PSU now good..

Ive got a bulb tester with croc clips attached n a 150w bulb..do i have to cut into vsus cable half way n run in series or just clip onto white connector on SN board..thx

Cut the VSUS grey wire mid point n attached bulb..fired up as normal
Soldered n taped wire back up n gonna run it a few hrs..ive treble checked my soldering with jewelers eye n tightened up the screws good..thx for info guys

[sienoki]

Re: Panasonic TX-P42ST31B 7blinks

Cut the VSUS grey wire mid point n attached bulb..fired up as normal
Soldered n taped wire back up n gonna run it a few hrs..ive treble checked my soldering with jewelers eye n tightened up the screws good..thx for info guys

If it was my set I'd put small heatsinks on all the IGBT's etc for good measure

[Moreno83]

Re: Panasonic TX-P42ST31B 7blinks

Ok , good! Your ps starts at 230???

Vsus must start with 207v and goes up to 215/216v on start up.
Your now running the tv with ysus?

[sienoki]

Re: Panasonic TX-P42ST31B 7blinks

Ok , good! Your ps starts at 230???

Vsus must start with 207v and goes up to 215/216v on start up.
Your now running the tv with ysus?

Watched it earlier for a couple hrs with no problems..Will keep testing it for a few days before returning it

[sienoki]

Re: Panasonic TX-P42ST31B 7blinks

Ok , good! Your ps starts at 230???

Vsus must start with 207v and goes up to 215/216v on start up.
Your now running the tv with ysus?

That voltage measurement was without X n Y connected..Will make sure it's correct values before returning it..thx fella

[Moreno83]

Re: Panasonic TX-P42ST31B 7blinks

Good job! Glad you fixed it.

Don't forget to use lock washer screws and please resolder the ground area on the back of the board.
And as you said , i always use silicon paste + heatsinks on all parts. Best is to use FGD4536TM igbt's , they don't get hot.

You did this just for 1 time or you keep repairing tv's?

Happy holidays!

[Alastair E]

Re: Panasonic TX-P42ST31B 7blinks

I second the cleaning of panel side, and re-tinning of all the mounting-points on any post 2008 Panasonic set and also replace the SN/SS board fixing-set-screws with ones having lock-washers,--take care you don't use ones too long if you're using S/H screws from summit else!
--Once re-tinned, remove as much solder from the pads as possible with braid, leaving the copper just silver-coated. You Do NOT want a thick blob of solder all around that ring/arch, as this over time will 'shrink' and leave the mount loose to arc again.

(I have a huge box of screws I raid and usually use the greenish ones from scrapped LG sets, they are just a tiny bit shorter than the originals.)

Ive just rebuilt a more basic 42U30B that has a similar idea SN board. I also added some heatsinks to the Buffer-Chips, and to the 30F131/DG302 IGBT's. A fan culled from a 40" FHD Samsung --the type with half one side missing,--I mounted above the lower set of 30F IGBTS and angled it to direct air upwards over the board.

I used some Old Stock 30F131 I bought about 3 years ago--Do NOT use any recent bought ones--unless from Panasonic Directly,--They are all FAKE now from other sources! Use FGD4536 now.

--Thing runs completely cold now on the SN side of the set.

Another important (IMHO) is to directly Solder the VSUS Supply power-leads from the PSU to the SN Board, as I have experience of a mis-hap and just a tiny poor connection on one end causing a rebuilt board to self-destruct again when I just brushed against this lead on a working set.#

--They ALL get soldered permanently now, Both Ends!....
(Pull the plug from the SC, Winkle out the metal plug part on end of lead from the plastic plug, re-position on correct SN board pin and solder the bugger solid to the pin--Both the supply and the earth return leads, then there's no chance of a tiny arc causing destruction of the board. )

[sienoki]

Re: Panasonic TX-P42ST31B 7blinks

I second the cleaning of panel side, and re-tinning of all the mounting-points on any post 2008 Panasonic set and also replace the SN/SS board fixing-set-screws with ones having lock-washers,--take care you don't use ones too long if you're using S/H screws from summit else!
--Once re-tinned, remove as much solder from the pads as possible with braid, leaving the copper just silver-coated. You Do NOT want a thick blob of solder all around that ring/arch, as this over time will 'shrink' and leave the mount loose to arc again.

(I have a huge box of screws I raid and usually use the greenish ones from scrapped LG sets, they are just a tiny bit shorter than the originals.)

Ive just rebuilt a more basic 42U30B that has a similar idea SN board. I also added some heatsinks to the Buffer-Chips, and to the 30F131/DG302 IGBT's. A fan culled from a 40" FHD Samsung --the type with half one side missing,--I mounted above the lower set of 30F IGBTS and angled it to direct air upwards over the board.

I used some Old Stock 30F131 I bought about 3 years ago--Do NOT use any recent bought ones--unless from Panasonic Directly,--They are all FAKE now from other sources! Use FGD4536 now.

--Thing runs completely cold now on the SN side of the set.

Another important (IMHO) is to directly Solder the VSUS Supply power-leads from the PSU to the SN Board, as I have experience of a mis-hap and just a tiny poor connection on one end causing a rebuilt board to self-destruct again when I just brushed against this lead on a working set.#

--They ALL get soldered permanently now, Both Ends!....
(Pull the plug from the SC, Winkle out the metal plug part on end of lead from the plastic plug, re-position on correct SN board pin and solder the bugger solid to the pin--Both the supply and the earth return leads, then there's no chance of a tiny arc causing destruction of the board. )

Thx for info guys..I've a bag full of screws from scrapped sets so will install locking washers..Will resolder tabs underneath..Gotta deal with reseating them buffer tabs tho 😥..they a pain in but..will solder vsus input cable direct to pins also..once again guys thx

[Moreno83]

Re: Panasonic TX-P42ST31B 7blinks

Thanks for the info Alastair. I do resolder the backside of the ysus board but just filling up the pads that are "gone". I got bad experience with the lock washer screws from 2008/2009 panasonic's on the 2011 boards. ( They have some green colour on them ).

Some how they damage the panel screw hole ....it's been 3 or 4 times now that i had to use a bigger screw to fit the board.
I now really clean up the solder pads and use the original screws as they also work on the SS board. I think that they just weren't tightened in the factory....


I also reworked a 42U30 , it has the TNPA5349 board. 2 30F131 / 2 RJP30H2A and 1 DG302 that were bad including the small buffer ic and transistor.
Tv is ok ....im wondering if I'm going to sell the tv or keep it as a test tv.....the Ysus has more value then the whole tv