Dell Inspiron 6000 battery warning light won't shut off?

I have an OLD Dell Inspiron 6000 laptop. At one point the battery ran down to empty just as I was doing a hibernate. In other words it never finished the hibernation process before turning off. Since then, the battery warning indicator light, below the lower right of the screen, won't stop blinking orange, even when plugged into the wall outlet. I have rebooted. I have removed the battery. I have fiddled with various power settings including those that should turn off the warning lights. None of these attempts have worked. Any thoughts on how I can get the system back to normal?