My k-cup coffee maker has stopped making coffee. It's a Keurig K45. It will take water, activate the pump, then it will just stay on the step with the red heating light on. I've let it sit for 15 minutes and it doesn't do anything. Usually it's just a few minutes before the blue cup lights turn on. Usually you can hear noise after the pumping which indicates the heating component is warming up the water.
Most conventional advice online only talks about descaling, getting air out of the tubes, and cleaning the metal punch that goes into the k-cups. So far I've unseated the water container, emptied it, refilled it, reseated it on the coffee maker, detached it again, turned the coffee maker over, tried giving it a few whacks to see if it would knock any buildup loose, and none of these did anything. The coffee maker is out of warranty.
What other steps can I try to get my coffee maker going again?