I don't know if this merits for Doofus, but maybe a reminder of "check the simple things first". Heater blower stopped co-operation two months ago after I managed to get horns operating with some creative wiring. I had one loose wire after that hanging and no heater blower. Well, I thought I might have done some damage to blower motor or shorted wires or whatever. I spend at least 10 evenings trying to find out where the loose wire is going under dash. Sight became always blurred, partly because of nice ergonomics under dash and partly because I was just hanging out in carage drinking beer rather than doing some household chores in home. This evening, I found it was a blown fuse. Ah, anyway, good beer. And I still don't know what's that loose wire.
Door handle first
Door handle first