Quote:
Originally Posted by YamahaFreak
UPDATE: Vs and Va voltages measure 197V (within 2 volts of rated 195) and 60 (right on) respectively.
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This is with all the board still connected?
If you look at the panel in complete darkness does it have a faint glow when powered up? (IE, is it getting precharge?) Check the rest of the voltages... If you have Vzb (panel bias, on the Z-sus board) then the Z is probably fine and I'm suspecting problems on the Y. Usually if the Z has a problem you will still get a picture it will just be dim and washed out with the panel bias absent.
Something must be missing... If all supplies are there everywhere it is possible that one of the IPMs failed open. They usually short but an open is certainly possible and it won't be generating any Yout signal to drive the panel. Can you post the best shot you can get of the whole Y-sus board? Perhaps I can spot some testpoints for things like the actual Yout signal to the panel.
If it does turn out to be a blown IPM you should check for shorts in the buffers on the Y-Drive boards, you certainly don't want to replace the IPM only to have it blow again due to a failed buffer chip.
Many of the IPMs are potted with a clear potting compound on the bottom and it is easy to see the blown FET/IGBTs from the bottom but it's nice to be sure it's frazzed before you bother to desolder it from the board.
Do you have an oscilliscope?