Gateway Solo 2100 Won't charge.

Solo 2100 Won't charge.

I bought a used Solo 2100 with a dead battery.
Replaced the cells.
Battery now seems to be working, but won't charge in the laptop.
If I charge it externally, the %charge battery gauge goes up.
Gauge goes down as it discharges in the laptop. Laptop works
just fine, lasts longtime.

When I plug in the AC adapter, the bios recognizes that fact
and the battery gauge in the OS, win98se, sez it's charging.
The charge indicator light on the laptop comes on indicating
that it's charging, but there's no current into the battery.
No upward change in the battery gauge reading. After several
hours the charge light starts flashing.

I need help from someone who's fixed this type of problem before
in THIS laptop.
Is there a fuse or a charge control FET in the path that
is likely the culprit? Where located?

Or maybe there's a magic incantation in the BIOS that I haven't
recognized as relevant.

I thought I could figure it out, but the thing is put together
in such a way that there's no hope of running it with the
case off. And the processor heat sink covers most of the top
side. A pointer to where the charge control components are located
(top/bottom of the board? approximate location? under the heatsink?
markings?) would be very helpful. I really don't want to go poking
around aimlessly. I'm likely to break more than I fix.

And yes, I am an electronic engineer and I have the instrumentation
and the smt soldering capability and safety glasses and insurance...
all I need is a hint so I don't disassemble anything that I don't need
to.

A schematic would be nice...yeah, I know, but had to ask...

Thanks, mike

--
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