Casio Cassiopeia E-100 Quit charging??

I bought an E-100. Played with it for a couple
of hours on AC power. Battery charge light was on.
I was downloading programs when I got an error from
active sync that the device could not be found.
Reset active sync and seems to work. I did notice that
file transfer was horribly slow, even for a serial connection.

I was also messin with 5V Compact Flash cards at the time.
They wouldn't read, but I later determined that it doesn't
support 5V CF cards.

The charge light was out...thought it had just reached
full charge. The device was rather warmer than I expected.

Anyway, the battery was not fully charged and the charge light
won't come on any more.

I can charge the battery externally. Internal resistance
is where it should be. Charges fine and runs the Casio fine.

I took the back off and determined that there's 5V inside the unit,
so the wall wart, cable and connectors are all working.

Before I take it further apart and risk messing up the display
cables, thought I'd ask if there are any common failure modes
that I should know about.
Schematic for the battery charge circuit?

Thanks, mike
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