Panasonic TX-P42C2l : No Power with 4 LED Blinks

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

thanks. IC 771;
Gnd - Out = 5.74k
Gnd - In = 1.72k

IC 773 (I don't sure about pin names. So I have mentioned the pin numbers mentioned on the board)
Gnd - 1,5 = 5.74k
Gnd - 2 = 1k
Gnd - 4 = 9.37k

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

thanks. IC 771;
Gnd - Out = 5.74k
Gnd - In = 1.72k

IC 773 (I don't sure about pin names. So I have mentioned the pin numbers mentioned on the board)
Gnd - 1,5 = 5.74k
Gnd - 2 = 1k
Gnd - 4 = 9.37k

Well that looks like they've survived

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Great really appreciate your help. I ordered everything i need from utsource. So will take 2,3 weeks.

Also can you let me know if it is possible to replace that power board capacitor (1000uf 230v) by 1000uf 250v or 1000uf 200v?
If not let me know if there any shop like utsource. cheers

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Great really appreciate your help. I ordered everything i need from utsource. So will take 2,3 weeks.

Also can you let me know if it is possible to replace that power board capacitor (1000uf 230v) by 1000uf 250v or 1000uf 200v?
If not let me know if there any shop like utsource. cheers

you'll have to match or go higher in voltage and I'd check the datasheet of whatever brand and series it is to something as good or better. Nichicon, rubycon etc.

I'd stay away from chinese sources for caps. I don't know who's in the UK, RS components, element 4

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

you'll have to match or go higher in voltage and I'd check the datasheet of whatever brand and series it is to something as good or better. Nichicon, rubycon etc.

I'd stay away from chinese sources for caps. I don't know who's in the UK, RS components, element 4

I found a closest match. please can you check it for me.
http://uk.rs-online.com/web/p/alumin...itors/7435438/

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

I found a closest match. please can you check it for me.
http://uk.rs-online.com/web/p/alumin...itors/7435438/

It would help to know brand and series of cap that's in there. I'm not a cap expert but that one only has 3000Hr life rating.

maybe http://uk.rs-online.com/web/p/alumin...itors/7149284/

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Hi just received the parts and replaced all the parts. But still I have the same 7 blink problem. Now I can see the SC board LED turning on. but go back to 7 blink mode after few seconds.

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Sorry it is 6 blinks now

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

It would help to know brand and series of cap that's in there. I'm not a cap expert but that one only has 3000Hr life rating.

maybe http://uk.rs-online.com/web/p/alumin...itors/7149284/

Hi, after replace the parts, it becomes 6 blinks.

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

do you think still it is SC board? please let me know what should i check now.

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

do you think still it is SC board? please let me know what should i check now.

Not good I guess. Not sure how I'll go recovering from a failed attempt.

Are you able to take a hi res photo of the board so I can see repairs? Can you list the parts(locations) replaced?

Did anything go pop when you powered this board up?

have you gone back and now checked all those parts to see if any are damaged/shorted after the power cycle?

Q661 is one that comes to mind

I'm hoping you ordered extra quantities of parts for more than one attempt.

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Not good I guess. Not sure how I'll go recovering from a failed attempt.

Are you able to take a hi res photo of the board so I can see repairs? Can you list the parts(locations) replaced?

Did anything go pop when you powered this board up?

have you gone back and now checked all those parts to see if any are damaged/shorted after the power cycle?

Q661 is one that comes to mind

I'm hoping you ordered extra quantities of parts for more than one attempt.

Please check the attached pic. checked the Q661 and its not shorted. and the other parts i replaced are looks fine. not shorted.

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Please check the attached pic. checked the Q661 and its not shorted. and the other parts i replaced are looks fine. not shorted.

I'm going to dribble out the info as I work out what those parts are.

Check D451 for short cct

Also looks like no 30f125 transistors replaced. Is that correct?

can you provide a summary of the part numbers of those heatsinked parts replaced, that will save me a lot of time.

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

What is Q621?

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Replaced parts:
Q661, 401, 402, 421, 422, 451
D482
IC521

Q451 - C & E shorted

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Replaced parts:
Q661, 401, 402, 421, 422, 451
D482
IC521

Q451 - C & E shorted

I think we're not understanding. I'd like the part numbers eg RJP63F3A etc

Check the SMD diode D451! The fact you report shorted C-E I think is pretty much confirming D451 is shorted, that will cause 6 blink and funny buzz

would like to know what Q621 is and also can you resistance that one g-c,g-e c-e.

Please

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

Actually if Q451 is short c-e, just remove that D451, recheck c-e, ,

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

you'll need either RF071L4S(original), RF101L4S(higher peak) (400V 1A) or something equivalent. super fast recovery diodes

[dulipra]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

checked D451 after removed. it is not shorted. transistor is fine. But the C & E points on board is shorted.
Pls can you let me know that diode part no on the board.

[tw2005]

Re: Panasonic TX-P42C2l : No Power with 4 LED Blinks

checked D451 after removed. it is not shorted. transistor is fine. But the C & E points on board is shorted.
Pls can you let me know that diode part no on the board.

Ok , this is weird. So out of cct, D451 is ok, so too is q451 out of cct but at the board c-e is?

I was confident i was right but looks not. we're close. Thinking Q551

Let me think. I may be misunderstanding the schematic.

back soon