Hey I have an old Inspiron B130. Seems the battery is bad, or maybe it's just not charging, or maybe it's just not working in some other way? My question is how can I test?
I don't want to just rush out and buy a new battery without knowing if the laptop battery subsystem is working. The laptop came from a person who "claims" that the battery is actually a new one. I can't verify, so I want to see if I can test the laptop itself.
I wonder if there are wiring diagrams or something where I can just test a few of the pins. Or I wonder if the pins are testable at all without a battery plugged in?

How can I make sure the battery subsystem works before I buy a new battery?

If you can't find any diagrams, just get a multitester, and with power off and pc unplugged, take out the battery and find pos / neg terminals on the computer against the chassis (unless they are labelled on the battery by chance?). Once you know which terminal is which, put the battery in the computer, let it charge (does the charge light come on? I should have asked that before). for a couple hours, unplug it and check the power. You may not see the full 11 volts (at least that's what I think the battery is on that model), but if it's charging, you should always have at least some residual power...

The battery light doesn't come on, but then maybe it does sometimes, similar to how XP shows the battery icon and sometimes not. Something is just funky in the subsystem, but can't figure if it's a funky battery or if it's the computer.

I'm not familiar with the Inspirons, But have worked on a laptop where the DC jack was loose from the mobo. It was an HP, but I'm sure it can happen to any laptop. Try powering on without the battery. If the light only comes on 'sometimes', it just isn't charging. I don't know how easy it is to access but if you can open it and check the jack it would be a good start. There should be markings on the board, but just check for continuity with power off.