Panasonic TC-P50C2 7 blinks

[tw2005]

Re: Panasonic TC-P50C2 7 blinks

Day started out OK. Read TW post and reseated the buffer jumpers. Took a little work and used a litle Deoxit on them. Got all the black lines cleared up. That was great and thanks TW. Still had the snowy dim picture. This is the bad part. Before i even got to take pictures i thought i would take some reading on the SS board. I was on Q102 and POP!!! My probe went source to drain. Now back to 10 blinks again. Didn't find any shorts on SS but SC shorted Q441,Q661,Q401,Q402,Q421 and Q422. So how have to order more parts from UTsource so on hold for a while. Thanks again and will get back soon.
Thanks Pudgi300

yeah, going to be a pain this one. That's what I don't like when the SS and SC are tied. One can blow the other. Have you ever repaired an SC before of this model?

Don't assume it's just those transistors gone. High chance there's a bunch of smd components gone too.

May want to look under my profile for threads started and raed the 5081 thread and the TH-P42x20a thread, there may be a couple of threads related to the X20 which is the same design as the C2 buthas a SN board but the cct will be the same.

pretty sure flocko has some experience on the same SN boards

If you get the sc going again I expect you'll be back to the same. Moduslinkpts do the 5063 boards for $65 repair/return

[pudgi300]

Re: Panasonic TC-P50C2 7 blinks

Back again but don't have all parts to fire it up again. Waiting on RJP3034. Can't find a datasheet anywhere for this igbt. Went on RENESAS and they have lots of information on discontinued products. I will post what happens when i get all the parts.

One thing i am having trouble with is the IC561 & ic562. Mine are 5mm in length. Every tssop-20 i find is 6.5mm. So question is where do i find a VHCT541A in a 20 pin 5mm length.

[pudgi300]

Re: Panasonic TC-P50C2 7 blinks

After a little more surfing i found the 5mm IC Datasheet for c541 buffer. It is called a VSSOP20-P-0030-0.50. Made by Toshiba p/n TC74vhct541afk. I found Panasonic parts at Sears direct. The C0JBAU000088 is $3.99 + shipping. Don't understand the p/n in the threads about PAVCTH C541. Can someone explain what i am missing. I hit the PAVCTH for Panasonic on Facebook and ended up with girls from Thiland in my Facebook.
My Q621 won't be here till next week so will post back what happens with the SC board.

[tw2005]

Re: Panasonic TC-P50C2 7 blinks

After a little more surfing i found the 5mm IC Datasheet for c541 buffer. It is called a VSSOP20-P-0030-0.50. Made by Toshiba p/n TC74vhct541afk. I found Panasonic parts at Sears direct. The C0JBAU000088 is $3.99 + shipping. Don't understand the p/n in the threads about PAVCTH C541. Can someone explain what i am missing. I hit the PAVCTH for Panasonic on Facebook and ended up with girls from Thiland in my Facebook.
My Q621 won't be here till next week so will post back what happens with the SC board.

Yes it's vssop and toshiba. If you did forum search on that panasonic number you would have found some threads of mine. Don't know where I put the real number but it's actually TC74VHC541FK. That other stuff is just copy and paste from the manual, maybe a panasonic warehouse location

$4 is rich, I got mine from UTSOURCE about 20cents in bulk. C541 is a partial number which is the marking on the device

not a part that commonly fails but can get damaged , I have a few since they were had to work out and find and now obsolete. panasonic were the only brand i saw these in that small. pain in the ass, next size much easier to source

RS online have them in europe probably don't do international

[pudgi300]

Re: Panasonic TC-P50C2 7 blinks

OK Got the SC up and running. Tested with P50 and ran clean. Put everything back together and the picture and sound come on but same as in the earlier post pictures. Snowy maldischarge. Flocko said he had same problem but don't know what he replaced. All my voltages are the same as before

Vsus 190.8

Led is on Green

TPVAD -190.8

TPVSCN -43.8

TPVE 124.6

TPSS 121.5
Thanks forany help

[tw2005]

Re: Panasonic TC-P50C2 7 blinks

OK Got the SC up and running. Tested with P50 and ran clean. Put everything back together and the picture and sound come on but same as in the earlier post pictures. Snowy maldischarge. Flocko said he had same problem but don't know what he replaced. All my voltages are the same as before

Vsus 190.8

Led is on Green

TPVAD -190.8

TPVSCN -43.8

TPVE 124.6

TPSS 121.5
Thanks forany help

I'd be inclined to think SS and since this happened last time too, maybe you'd be better off getting a known good ss because the SS can take out the SC in this setup. Did you replace the M81735P fet IC?

[pudgi300]

Re: Panasonic TC-P50C2 7 blinks

Thanks TW. Pulled the SS board today and started checking q161 back to ic131 pin 1. Found that when i took q161 out to check out of cct i must have moved R161 the 10 ohm resister. I replaced the r161 and for good measure replaced q141 and 161. TV came on with good picture. Will post wrapup later.

[tw2005]

Re: Panasonic TC-P50C2 7 blinks

Thanks TW. Pulled the SS board today and started checking q161 back to ic131 pin 1. Found that when i took q161 out to check out of cct i must have moved R161 the 10 ohm resister. I replaced the r161 and for good measure replaced q141 and 161. TV came on with good picture. Will post wrapup later.

funny I was almost going to ask about resistors disturbed. I did the same thing and lost the 100ohm resistor on the input side of that fet driver. would give the same result as what you did as those IGBTs off that would not be driven.

Why i suggested a new ss, thought the chances of you finding something missing would be slim and safer than blowing the sc again but good recovery finding that.

[pudgi300]

Re: Panasonic TC-P50C2 7 blinks

One other thing with this SS board. I bought the repair kit from Shopjimmy. My original 2 RJK2017 fets tested fine (used atlas dca55) but wanted to replace them anyway. Tested the 2 RJK2017 fets in the kit and they failed. Shopjimmy sent me a new kit free of charge. Tested the 2 RJK2017 fets and 1 of them said it was a n-ch fet. Told Shopjimmy again and they said they would check with their tech. They never got back to me. In the meantime i ordered RJK2017 from utsource but orderewd t0-220 instesd of surface mount. I tested them and they tested perfect. Now have to order RJK2017DPE from china again. Two weeks later send Shopjimmy e-mail that they did not get back to me and that the RJK2017 fets they sent me had ( all 4 of them) 17k ohms between source and drain when turned on. The original and utsource fet would go very low resistance turned on. They e-mailed me back and said they would check on it but have not responded in a week. Now i get my SC board working but want to replace the original RJK2017's and don't have any except the t0-220 config ones. So put them in and attached a heat sink to them and TV is working fine. The main point of this is if i didn't test the RJK2017's from Shopjimmy i might have blown this thing up a few more times. Will post a recap once the rear cover is on. Got 2 new RJK2017DPE coming tomorrow. Any hints on why those fets have 17k source to drain?

[tw2005]

Re: Panasonic TC-P50C2 7 blinks

One other thing with this SS board. I bought the repair kit from Shopjimmy. My original 2 RJK2017 fets tested fine (used atlas dca55) but wanted to replace them anyway. Tested the 2 RJK2017 fets in the kit and they failed. Shopjimmy sent me a new kit free of charge. Tested the 2 RJK2017 fets and 1 of them said it was a n-ch fet. Told Shopjimmy again and they said they would check with their tech. They never got back to me. In the meantime i ordered RJK2017 from utsource but orderewd t0-220 instesd of surface mount. I tested them and they tested perfect. Now have to order RJK2017DPE from china again. Two weeks later send Shopjimmy e-mail that they did not get back to me and that the RJK2017 fets they sent me had ( all 4 of them) 17k ohms between source and drain when turned on. The original and utsource fet would go very low resistance turned on. They e-mailed me back and said they would check on it but have not responded in a week. Now i get my SC board working but want to replace the original RJK2017's and don't have any except the t0-220 config ones. So put them in and attached a heat sink to them and TV is working fine. The main point of this is if i didn't test the RJK2017's from Shopjimmy i might have blown this thing up a few more times. Will post a recap once the rear cover is on. Got 2 new RJK2017DPE coming tomorrow. Any hints on why those fets have 17k source to drain?

No idea but by the sounds of it all they're probably getting their stuff from china too. So what do we really get OEM genuines or chinese copies? I have my doubts too ut everything I've had from UT in china has worked.

I've been lucky to date with UTSOURCE but considering the stuff around etc I probably would have just left the originals in play but I can understand you wanting to replace them.

certainly you could use the other package with a heat sink but I'd just get the right part.

I don't know if simply doing a resistance check is an accurate way to go about checking though.

If you google test FETs there is a video someone did, that's what I do and I had no idea until i saw that. I use diode mode to switch the fet on then check it's on, the short the leads then check it's off

here's one, not the one I first saw

https://www.youtube.com/watch?v=gloikp9t2dA

and here's an IGBT
https://www.youtube.com/watch?v=AfV7gYChILc

[pudgi300]

Re: Panasonic TC-P50C2 7 blinks

Hi TW. I check them with my dca55 checker. At 1st i thought they were IGBT's and my tester doesn't test IGBT's. Then realized the K in RJK means FET. I also tested them in diode mode. I can charge them up with diode mode to the gate and and back to the drain and it is on. Touch gate with finger and it turns off. Only problem is when it is on it will read .4800 instead of .0000 source to drain. Turn it off and reverse probes source to drain and it will read .3900 . Only the ones from Shopjimmy read this way. Got 2 new ones coming tomorrow and let you know the reading and the date codes. Been playing the TV almost 3 days now and the RJK2017's with heatsink are staying cool. Oh the 2 RJK2017 fets are rhe ones it hit with my probe and blew the SC board. So i don't trust putting them in because they may have internal damage.

[tw2005]

Re: Panasonic TC-P50C2 7 blinks

Hi TW. I check them with my dca55 checker. At 1st i thought they were IGBT's and my tester doesn't test IGBT's. Then realized the K in RJK means FET. I also tested them in diode mode. I can charge them up with diode mode to the gate and and back to the drain and it is on. Touch gate with finger and it turns off. Only problem is when it is on it will read .4800 instead of .0000 source to drain. Turn it off and reverse probes source to drain and it will read .3900 . Only the ones from Shopjimmy read this way. Got 2 new ones coming tomorrow and let you know the reading and the date codes. Been playing the TV almost 3 days now and the RJK2017's with heatsink are staying cool. Oh the 2 RJK2017 fets are rhe ones it hit with my probe and blew the SC board. So i don't trust putting them in because they may have internal damage.

yeah, once bitten, twic shy. I have the same issue with the 42". i have a ss I've repaired a second time and a sn that needs a rebuild but I'm a little too scared to stuff around as the original SS repair lasted 4 days then blew bot Sn and SS. Still have a spare SN and SS in original condition for it so not too concerned about getting back to fixing my boards.

[pudgi300]

Re: Panasonic TC-P50C2 7 blinks

Here is a little recap of this repair. Won't tell how much i spent on parts. TV is working fine so thanks to TW and Flocko.

Start 10 blinks replace on ss board q001,q002,q021,q022 IC131 startup and 7 blinks


7 blinks replace on SC IC771 IC521 Q701,Q702 IC501 Q661,Q651,D481,D451 STARUP WITH P50 JUMP OK
CONNECT BUFFER AND GET PICTURE BUT MALDISCHARGE. WAS PROBING SS BOARD AND SHORTED SOURCE TO
DRAIN ON Q102 AND BLEW SC BOARD.
REPLACED ON SC Q701,Q701,D701,D702,IC771,IC773,Q441,Q661,Q401,Q402,Q421,Q422 ON SS IC131
STARTUP CHECKED BUFFERS CLEAN SETUP FOR P50 JUMPER AND WAS CLEAN. CONNECT BUFFERS AND BACK TO

MALDISCHARGE. FOUND R161 MOVED WHEN I REMOVED Q161 TO CHECK. REPLACE Q141 AND Q161 AND PUT R161 BACK IN ITS PLACE. TV HAS HAS BEEN WORKING FINE SINCE.

[Andrew F. Ali]

Re: Panasonic TC-P50C2 7 blinks

Great job!!!