TH-P50G15A - 6 Blinks- Bad TNPA4782

[Glitcher]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Got into the service menu. I went into serv tool and held the return, the tv just resets and brings me back up to the main service menu.

looks like this set only had 5700 hours on it.

[Alastair E]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

TBH--The screws were not slack or any evidence of arcing, I pulled the board just to check.

No evidence the board has ever seen an Iron --or anything else. If it had been given to me as a brand-new part, I wouldn't have cause to say otherwise, Looks perfect!

Ive bunged it on the wall anyway--Got fed up with the Cruddy picture on that 4K LG LED set--HATE LCD pictures.....

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

TBH--The screws were not slack or any evidence of arcing, I pulled the board just to check.

No evidence the board has ever seen an Iron --or anything else. If it had been given to me as a brand-new part, I wouldn't have cause to say otherwise, Looks perfect!

Ive bunged it on the wall anyway--Got fed up with the Cruddy picture on that 4K LG LED set--HATE LCD pictures.....

I did'nt think you thought much of the panasonic plasmas either?

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Got into the service menu. I went into serv tool and held the return, the tv just resets and brings me back up to the main service menu.

looks like this set only had 5700 hours on it.

ok, thanks but normally it would restart and turn on like normal TV. maybe the setup is different. I was hoping the missed Pfet on mine may have been the cause of this minor issue.

You're going to finish this off properly and replace the FET?

Well we got there in the end, now find another and have another go

[Glitcher]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Yep, and thanks for all the help! Maybe I should start fixing these three 5081 boards I have laying around.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Yep, and thanks for all the help! Maybe I should start fixing these three 5081 boards I have laying around.

Oh, you're kidding you have these laying around! You can fix those easy. How many parts do you have left over?

[Glitcher]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Not much parts left for now. Probably need to order more. Might be hard to fix these since I don't have the panel anymore

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Here's another way to remove those M81737 Ics, use a precision set of cutters and carefully nip the legs against the casing. Desolder the remnants, use a quality braid like chem-wik to remove all solder , clean with IPA, get some flux or flux pen and prep the pads and legs, tack 2 corners to get it nicely in position and use fine solder and fine tip.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Not much parts left for now. Probably need to order more. Might be hard to fix these since I don't have the panel anymore

yeah, that would be tricky for testing and you can't plug it in this model either as the Sc20 pinouts are different. You could plug in to a S20, (s2)

You'd need RJp63F3a, DG402RP x 2, 30F125 x 2, dg502LW x 2, 45G128 x 1, RFN25TM4SW or a 400v 20A fast rectifier, M81737FP, TC7SH14F, MMBTA92, 2PD601ART, 2sk3018 or 2n7002, RF071L4s or RF101L4s, TA78L05

I have done some with only 7 or 8 parts needed but above is fairly normal, CPH5524 would be handy but normally they seem ok,

[Glitcher]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

I usually use an exacto knife but being careful not to put too much pressure as not to cut the traces underneath. But that's only if I know it's definitely bad. Sometimes I end up wanting to put it back for some reason. I usually put a blob of solder of both ends and heat both ends with my iron until it finally loosens off

[vinceroger69]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Just read this post from start to finish a good fix and some good info on test procedures etc whats the rough cost for the parts per board? compared to a good used one? Not everyone maybe able to complete this fix i guess due to small parts (smd)?.Can this repair be carried out with just a soldering iron or do you need hot air station? cheers for any advice you can offer. I havnt got a board needing repair but having this info in advance is always handy for myself and maybe other members.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Just read this post from start to finish a good fix and some good info on test procedures etc whats the rough cost for the parts per board? compared to a good used one? Not everyone maybe able to complete this fix i guess due to small parts (smd)?.Can this repair be carried out with just a soldering iron or do you need hot air station? cheers for any advice you can offer. I havnt got a board needing repair but having this info in advance is always handy for myself and maybe other members.

I only have the most basic gear, use 2 irons to remove these smaller items heating both sides and use the tips to move them. I have a headband magnifier and a 5x loupe to get a good look at the finer pitch items like those 20 pin octal buffers which are large compared to the 5081 boards. have tried flooding the pins on the FET drivers but mixed results and the heat easily lifts the no connection pads plus very cramped.

I think anyone who has hot air and experience may do a better job.

maybe one day I'll get a cheap Hot air station and have a go

Cutting the pins makes it easy and I think once you've done a few for what these parts cost better to just replace and treat these drivers as suspect but I must admit with so litle blown on my first 4782 I got lazy and skipped it.

Going to depend on how much is blown as i've read a lot more IGBTs need replacing so plenty of scope for these to be hard.

sometimes you just have to have a go to learn and not give up if possible.

I would say about $20, going to depend on where you get the bits, qty purchased and you'd be mad not to get extras just in case so the first board may need a $40 investment.

looking at the time and possibility of failure, what people charge is probably cheap really for the effort but the more boards you do the more knowledge and more efficient you get.

I think it's fun but lets face it if nobody tried then there'd be a lot of tvs not repairable due to no boards available and buffers are a concern now. i keep all the dead boards just in case and for learning. I'd like to have a go at buffer rebuilds but too expensive for the panasonics i feel and I think hot air would be a safer option.

looking at these 4788,89 buffers, 8 Ics, about $50-60 AUD and you only need to stuff one track up and it's all over, very risky for me at least.

Both of the boards i killed all 8 ics have 1 shorted pin

[vinceroger69]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Thanks for the information.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

Oh, I should mention FLUX, flux pen, makes a world of difference and flows so nice which is what you need to avoids bridges.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

my 2 very cheap irons, 20W & 40W with a quality tip in the 40w

Also a set of quality fine tip tweezers is handy for handling and placement of the SMD stuff

[vinceroger69]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

cool thanks i have most of the stuff already minus flux pen (have you got a link which one you use) also need a jewlers loupe they always come in handy i guess cheers again.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

cool thanks i have most of the stuff already minus flux pen (have you got a link which one you use) also need a jewlers loupe they always come in handy i guess cheers again.

No, just a generic flux pen from a local electronic shops Jaycar. Called No clean flux pen. They're not cheap about $12 AUD but for this work I find it invaluable.

[tw2005]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

maybe something like this but it's a pack of 5 so over 20GBP

http://uk.rs-online.com/web/c/?sra=o...hTerm=flux+pen

http://uk.rs-online.com/web/p/solder-fluxes/2513637/

[vinceroger69]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

maybe something like this but it's a pack of 5 so over 20GBP

http://uk.rs-online.com/web/c/?sra=o...hTerm=flux+pen

http://uk.rs-online.com/web/p/solder-fluxes/2513637/

Thanks for the rs link i have a branch a short distance from me having five is no problem im sure they will come in handy for other project, im just looking on all my free sites local to see what project tvs are available why pay i say if i can pick them up for just the fuel cost.

[Alastair E]

Re: TH-P50G15A - 6 Blinks- Bad TNPA4782

I did'nt think you thought much of the panasonic plasmas either?

Well--Not certain models for sure!

The older series like the TH-p42/50/PX/PZ/70/80/81 series are brilliant long lived reliable sets.
--Just a shame they double as room-heaters!