HITACHI 55HDS69 power, sound but no picture

[sessarhack]

HI folks this is my second post, recently i buyed a Hitachi 55" HDS69 with the no picture problem, i check the picture output (RCA) and i have picture. I check the CN99 for VS, VA but nothing, i check the mosfet´s but i´m not shure if doesnt work.

Also i found a not working IRFS634b i´m trying to get another to check Va & Vs


if somebody know about this plasma, please let me know.

cheers!

[sessarhack]

Re: HITACHI 55HDS69 power, sound but no picture

***Update

After remove the IRFS634b the mainboard power up, stay on for 10 seconds an then shut down, but the worst part it´s the IRFS634b have some failure, here i can´t find the same mosfet, i´ll try with the STP16NS25FP to replace the other mosfet.

cheers



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[sessarhack]

Re: HITACHI 55HDS69 power, sound but no picture

Hi everybody! well i found a curious problem i have to buy another psu but i have the same issue, no Va & Vs, but this time i decide to explore another solution, i reflow the "logic buhin Board" and i have 5v in the grey wires, then i suppose something happening, but no...then i check the buffer board for something wrong, and i found 4 polyester cap burned, 2G103K i google this cap, and i found it´s a 400v polyester film capacitor 10x100 10% tolerance. so i got to buy some and test again, also i reflow the buffer chips, it works on a hitachi 42 with black stripes. i´ll upload pics asap.

[tom66]

Re: HITACHI 55HDS69 power, sound but no picture

This may be of some use

[Nick's Tvs]

Re: HITACHI 55HDS69 power, sound but no picture

Tom66
I have the same issue with this tv, and I looked at the troubleshooting flow chart on page 52 of your service manual that you linked above. I do have a problem however, if you go down to page 53 it will show you the different LED pattern that you are having and tells you where the issue is coming from. However it doesn't tell you for every pattern. Some are blank. Mine is pattern 14 with the 3 middle LED's being lit. What does this mean? How do I figure it out?