But your linked doc includes the same anomalous language...
The language you quote isn't so much
anomalous as as
generic: there is a problem, specified by the
pattern of the flashes as outlined by the KB article. Apparently ynotmit noted three short flashes of the display's power light, because when he checked that phenomenon in his display's manual he came up with exactly the same diagnosis as the KB article I quoted.
That said, the problem is now why the PRAM reset won't seem to work. There's also the possibility that the G4's display hookup isn't OK; perhaps it was incorrectly reconnected for this particular use after sitting idle for a year, the video card got bumped loose while setting up, or a relevant file in the OS got florfed somehow. I'd start with reseating the videocard and checking any associated cable hookups.
