Fujitsu PDS4208 42" Plasma Help

Fujitsu plasm

VirusCrazy,

I know its an old post but if you are still around I need some of your knowledge of the Fujitsu Plasma PS board.

Just acquired an nice Fujitsu PDS4207W-H.

Looks and works great--until it doesn't.

Shuts down after an hour or little less depending on ambient temp. Some sort of thermal thing.

Before I start fiddling around trying to figure out how it all works can you tell me what voltages I should be seeing and what the protection circuit is watching so I can watch same? My first suspicion is thermal sensor board but I would love to just cut to the chase.

Merci,

I know this is old too but am also after advice.
I have p42hhs10... fujitsu with the now famous red continuous blinking light problem.
Set turns on ok but may only run for 30 mins or less and just shut down for no obvious reason and ends in continuous red flashing led. After hearing a relay or something click and switching power back on it starts ok and then does same thing.

I have had the power supply out and inspected it but found no obvious signs apart from a few crazed solder joints which I repaired but same thing when I put it back together and tested it. All the service bulletin fixes have been implemented with no luck either. I am leaning toward thinking its one of the big five legged ic's attached to heat sink or faulty psu protection circuit but it could be anything.

My question is, being that I dont have wiring diagram, do these relays cut in as part of the protection circuit to shut the power down? and if so is there a way I can bypass the protection circuit and wire it to an always on state?

really appreciate any help or advice. The set just totally loses power randomly without any other signs or symptoms and five mins later whatever the problem is has cooled enough to let it go for another random amount of time. (continous red flashing light until restarted)

just to update, i adjusted vs and va on power supply and its working perfectly now. thanks to one of the previous posters for suggsting it.

actually scrap that last post, though it did help, now i can get an hour or so before it shuts down. any ideas? i am about to try totally bi-passing the protection circutry and wiring the relay so it cant shut it down. i know this is not good from a safety point of view but i cant keep wasting time on this and i have been quoted 900 dollars for replacement power supply and repair. i am ready to trash it but its a shame to trash a set that was 10,000 new and still works fine apart from random shut-down.
any ideas much appreciated.

Hello,

Sorry to bring up on old thread. I have a Fujitsu Plasmavision 50, that will not power up completely. Green led will be on for 10 seconds, and then red for 3 seconds. Relay clicks when powering up, but immediately clicks back (off). Display will not turn on.

I've collected some service manual, the question would be, What will be the reference (ground?) point to check and set Vsus, Va etc? I assume these are AC voltages?

Thanks much!

Ben L said:

I've collected some service manual, the question would be, What will be the reference (ground?) point to check and set Vsus, Va etc? I assume these are AC voltages?

Click to expand...

No, they are DC voltages - and the reference is chassis - however, as you obviously know nothing whatsoever about electronics I would STRONGLY suggest you don't take the back off.

Dear Nigel,

Thank you for the info. But unfortunately the unit died because of a lighting strike through a DSL modem, taking out the unit, modem and a wifi router ;(.

I opened the unit and found an IC broken apart. Can this be IDed? Any other part will be damaged apart from this one? Interestingly the fuse is not blown off. If this is replaced, any posibility this unit will work again?

Look forward for your guidance. Thank you.

Best regards,

Ben

Ben L said:

Dear Nigel,

Thank you for the info. But unfortunately the unit died because of a lighting strike through a DSL modem, taking out the unit, modem and a wifi router ;(.

I opened the unit and found an IC broken apart. Can this be IDed? Any other part will be damaged apart from this one? Interestingly the fuse is not blown off. If this is replaced, any posibility this unit will work again?

Click to expand...

Fujitsu service policy is to only supplied replacement PCB's, so you would probably need to see a working board to read the number from it, then see if you could source a chip.

It looks to be the standby PSU chip - and if you're EXCEPTIONALLY lucky, it 'might' just be the IC. However, I've repaired (and tried to repair) a great many lightning damaged sets over the decades, and in the vast majority of cases there are multiple faults, often totally unrelated. I've even repaired a couple of CRT sets over the years, mending 15-20 faults on each one , only to find the CRT was damaged as well - actually physically distortion of the shadowmasks, giving a sharply defined purity error.

As for the fuse - fuses often don't 'blow' in lightning strikes, they are either intact - or completely blown to pieces, with even the fuse holder vaporised as well

It should be possible to identify the IC from the service manual. I suspect that it is an opto isolator based on the slot in the PCB under the IC. (To provide better isolation between the two sides of the opto isolator.) There is a high probability that there are other damaged components that cannot be identified visually. I would strongly advice taking Nigel's advice not to try to repair this item due to your limited knowledge and the high voltages involved.

Les.

Les Jones said:

It should be possible to identify the IC from the service manual.

Click to expand...

As I've already explained, Fujitsu only supply replacement boards, there are no circuit diagrams or component lists in the service manual - at least not the ones I've seen.

So you can't identify the IC from the service manual, or even confirm there's an IC used