The touchpad on this dryer has at times not responded at all, or worked perfectly, worked after unplugging, worked after working the buttons, beeped erratically during drying, worked after heating the back/front of the touchpad and/or control panel with a heat gun, etc. It has not worked consistently for more than 2 weeks at a time (usually stops responding to touchpad keys completely), in a long time. I have done the various key matrix resistance checks on the individual buttons, and at times all but a few of the buttons are bad (and it is not always the same buttons that are bad). Then I have tested it other times, and all test out good and the touchpad works perfectly.

UPDATE: Replacing the touchpad/control assembly fixed the problem.