Question : Problem: Battery discharges on Evo N400c/Also when on battery, the power controls say it is on AC Power

Battery discharges on Evo N400c/Also when on battery, the power controls say it is on AC Power....I have a couple of these Compaq Evo N400c notebooks with expansion bases.  Oddly enough this particular one runs great in the base, and out of the base while it has the AC Adapter plugged in, when I put a perfectly good battery in the laptop and unplug the AC Adapter the icons and the power meter both say the laptop is still plugged in to the AC Adapter.  Also a battery which when fully charged in another laptop, same model and configuration, which lasts two hours, when that same battery fully charged is used in this laptop it discharges within 15 minutes and the laptop hibernates.  HELP!

Answer : Problem: Battery discharges on Evo N400c/Also when on battery, the power controls say it is on AC Power

I'm sure now that the charging/battery circuit (power board section) of your motherboard is bad.

If you can live with AC power just leave the battery out (to prevent more damage) and run on AC.
If you want backup power for power outs plug the AC adapter into a battery backup as with a desktop computer.

If AC isn't acceptable you need to replace the motherboard or the laptop.

Sometimes a good route (especially since you seem to have more than one of this model laptop) to replace a laptop motherboard is to find a known good and working laptop on eBay with a damaged screen. Probably less expensive than buying a motherboard outright and you could possibly end up with other spare parts for later. (Keyboard, touch-pad, drives, screws, CPU, memory....)

Alternately you could buy a stripped one. Good mainboard but no keyboard, drives, or memory. Some of those have good screens (for a spare) and some don't.

PCBONEZ
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