Hog wash I say!
Check out the side of the black cartridge, notice that clear window looking thing. Cover it with black tape, or in my case a piece of paper held on by regular tape, and that puppy will fire up printing again!
From what I’ve read it has a sensor that checks for infrared passing through that window from one side to the other. Unfortunately, the way the cart is designed you wind up with a lot of waste that is enough to print for a good while but not enough to block the light.