Help repairing plasma tv 42pd5200

[portishead]

Hi all.,
I am trying to repair a tv of mine.Its too good to throw away. A Hitachi 42pd5200 plasma. It stop turning on the other day. I have searched a little and it looks like the power board perhaps but I cant be sure.
I need to find a kind person that can help me find the faulty component so I can remove and solder a new part if necessary

I have stripped the tv and taken off the power board to look at.

If there is anyone here that could help me with the use of my multimeter etc I would be very grateful

thanks all.

 

[davenn]

hi there
welcome

show some sharp and well lit pics of the PSU board .. clear enough so that the component names can be read

have you googled for any service information ? schematics or full service manual would be helpful

 

[portishead]

All I can say is I've come across this on ebay. I've tried to ask the chap about it but not getting anywhere.

Is the picture any good?

It's power board mpf7409

http://pages.ebay.com/link/?nav=item.view&id=331810722424&alt=web

 

[73's de Edd]

Sir portishead. . . . . . .

Do any power designating LEDS on the sets front light up?

Track down the AC line cord path going to a shielded line filter network and it exits as E902 connector which connects into a small PCB silk screened as . . . . ."FILTER".
See if that boards F952 10amp/250 v fuse is blown.
Thereby . . . . . ascertaining if you have had a "HARD" failure . . .or hopefully not . . .and thereby a "soft" failure .

If not, then the next area of inspection will be the power supply board . . . ."Power Unit" :

Inside Back Referencing:

73's de Edd

 

[portishead]

Ok, so the green power light comes on when I turn the set on. It continues to stay on after it turns it self off.

I have found a fuse as in the picture attached. But it's marked differently if you'd take look...

 

[73's de Edd]

That's good on the GREEN LED . . .that means that the units standby power is operative . . . .and that also might tell us that the remote section and a hunk of its associative u/p circuitry is operative, if you can turn on the set with your remote.
And yes . . .your Flag tells me you have 220V AC power . . .while mine tells me 120V AC power . . . . half the supply level . . .thereby . . . your unit is using but a 6.3 A white ceramic fuse.
It will be good . . .because your standby power supply is downstream from it. . . . .HOWEVER, there are 4 others power levels being produced on that PS board.
On that e bay kit that you referenced us to, the 10 ohm fusing / resistors are at the top left of that Power board and you can ohm them out . . .but I feel that they will also be good.
See if you can find those referenced . . . . two (2S) K2843's mounted on your power board . . .probably mounted on a heat sink . . . . and of the same numbering, considering that they did not sub in different new parts numbers.

 

[portishead]

Thank you very much again for all this help. Very generous.

I have located the two k2843 as pictured. What should I do with them?

 

[73's de Edd]

Initially . . . . .ohm out to see there is a low resistance "short" between the Drain and Source of either unit , , ,and then check between all gate- drain- source possibilities.

Looks like one is assigned a Q201 identifier and the other 220 . . . . .hmmmmmm . . .wonder why it wasn't a more logical Q202 ?

 

[portishead]

I don't know what that means to be honest!

 

[73's de Edd]

" If there is anyone here that could help me with the use of my multimeter etc I would be very grateful"

I thought that you knew how to, and were capable of taking resistance readings with that afore mentioned VOM . . . . .
Either consult the internet for learning . . . . .OR . . . . . do you have any acquaintances that are "electronics " savvy ?

HEY ! . . . .I do now see that I fully neglected to give you the drawing of the FET and its basing . . . that should make more sense to you now . . . .

 

[portishead]

Ok. Ill take a look and see how to set the meter and test these.

 

[davenn]

All I can say is I've come across this on ebay. I've tried to ask the chap about it but not getting anywhere.

Is the picture any good?

It's power board mpf7409

http://pages.ebay.com/link/?nav=item.view&id=331810722424&alt=web

no, not really

I wanted to see pix of the board from YOUR TV
I wanted to see if there were any obviously failed components I could pick out and get you to replace


Dave

 

[portishead]

Hi Dave. That is a picture of my plasma power board.
Can I get you another image??

 

[portishead]

Hi guys. Any further thoughts. Tested the ceramic blocks and the two transistors. They appear fine.
Anybody know where I can look next??