Casio CZ/ VZ/ FZ - Pro Series

Howdy yall. I just bought a CZ101 off of ebay....I love the sounds!

Unfortunately I think i got jipped because I am not able to get the 
Internal Memory led to light at all. I try editing a patch then 
holding write and pressing the Internal Memory button....nothing. 
Also SoundDiver cannot write to the user banks either, indicating to 
me that its not just the Internal Memory button. 

Has anyone else heard of this problem at all? I can't find any 
information on any forums nor the internet. If someone knows how it 
can be repaired I am quite handy having repaired other synths in the 
past, but the CZ-101 seems like a real pain after having cracked the 
case and had a look.

Is there indeed a lithum battery somewhere in there, or could the 
user RAM have gone bad? Considering the amount of bends people 
perform on these babies there has to be some more technical info out 
there.

Thanks so much for any help at all. 

                                        Drew