Within your printing options/properties there is usually a way to select to print only in black. If not you can choose it to print in some sort of draft mode that should use a light gray scale when printing.
Epson cartridges have little chips on them that are used for sensing if a cartridge is empty or not. I had a buddy who would fill his own and had a device he would have to basically scan over the cartridge in order to "reset" the chip.
So if you think there is still ink in there you could try resetting the chip.