How do you get the printer to recognize that the cartridge is now full? -

Is there a special tool for re-setting the chip that tells the printer that the cartridge is full?

Nope. Did you refill the cartridge? Shame on you, that can damage the printer and is probably why it s not working right.

take it our and turn off the printer then put the ink in and turn it on!

Those things are seldom right anyway. Change the cartridge when you run out of a color of ink.