Help! IIgs is broke

[ltw@vms.cis.pitt.edu]

It has been a few months since the IIgs was last used but it worked fine then. 
Now, I only get the splash screen (ROM 01) with no polling of drives and no 
access to the control panel. Also can't seem to run the diagnostics 
(Control-option-reset?). The machine is fairly loaded, including a ZipGS. The 
red and yellow lights are illuminated on the Zip card.

I thought I'd ask here before I pull the Zip card and reinstall the original CPU 
chip. Even a dead battery should allow me to access the control panel, right?

Thanks for any ideas.

--Linda