Aspire 5315 battery problem

The battery on my 5315 won't charge any more. When I plug the AC adaptor in, the Power light flashes yellow and orange, and the Battery light flashes orange. I don't know what these lights mean; can anyone help?

 

Could be a faulty battery but try this first. Remove all AC power and the battery and then hold the power button on for 20 seconds or so. Replace battery and try again.
Does the laptop all work OK otherwise?
If not does it work if you remove the battery?
If still no good are you able to measure the voltage across the terminals of the battery. If very low battery probably faulty.

 

Everything works fine otherwise; the laptop boots and runs normally.

I've tried it with two batteries, although both are run-down and nearly dead, and it happens with both.

When I connect the AC adapter without the battery, it'll boot up fine, but will randomly shut down for no reason... this leads me to believe that it's either the AC adaptor or (gulp) the internal power connector.

Also, the battery seems to be misreporting its status; it's been on "0%" now for 10 minutes, beeping away but running normally without hibernating. Could this be related?

I tried holding the power button down; it didn't make any difference.