[SPARCbook] Reviving a Dead SparcBook 3GS - stuck booting

[Barry A. Dobyns]

I have a Sparcbook 3gs that hangs when I turn it on.

The LCD displays 
0D0 for about half a second, then 
007 for about three seconds, then 
001 and hangs there forever.

The LCD screen never lights up and the keyboard is unresponsive (Pause-R, Pause-A don't work).

Previously it was running Solaris 2.5.1 fine

I've tried removing the battery and AC power for 48 hours, to no avail.  
I've reseated the memory and hard disk as well.

Suggestions?

-b
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Barry A. Dobyns, barry at dobyns.com, http://barry.dobyns.com