Latitude Z 600
minor liquid spill while computer was off and not plugged in- mainly hit the a/c jack - female input of laptop
problem then was laptop now ONLY works on a) battery alone without a/c charger or b) a/c alone without battery
otherwise with battery in and a/c plugged in the a/c charger shuts off
tried starting up on a/c and then plugging in battery BUT NO GOOD - a/c charger cut power - same with the opposite running on battery and then plugging in a/c adaptor - adapter shuts off
NO PROBLEM REVEALED ON DIAGNOSTICS - NO OTHER PROBLEM WITH COMPUTER
I just replaced the laptop power-in jack - this did not fix problem
Can't flash the BIOS which requires both a/c plugged in and battery
While it's possible the battery was damaged, it's far more likely the problem is a blown charge circuit on the system board.
Next logical step - replace the mainboard.