I've found several reports on people with bad internal charging circuits for
Dell Latitude PCs (I currently have a Latitude C600).

The symptoms include:
-Battery does not charge
-High pitched noise coming from motherboard when plugged into AC adapter.
(this is not fan noise - most likely FET?)

I cannot seem to find any information on how to fix (mine is out of
warranty). This sounds like a pretty common problem so I was hoping that
someone here had some additional information on how to fix. This is not a
battery problem as both charge fine in other laptops.
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