Welcome to TechIMO!
From a translated page I found:
1x long, 2x briefly Diagram map error : Video Rome BIOS - check sum wrongly; Monitor control defectively; no diagram map found; Parity error.
It can be seen
here (not sure if the translation will take).
I would try a few things here.
1. Swap out the memory with known good memory (1 stick) and / or;
2. Swap out the video card.
And pull the Lithium battery for a minute or two and try rebooting.
If all else fails, I flashed a BIOS a few months ago with the wrong version (ooops

). I found a guy that had me a new EEPROM chip here in 3 days. I hope that's not what it takes for you

.
Mike