Go back and reread what you just wrote. The Heater blower motor ground shares that contact!
That may be your Bingo!
Clean the contacts, and try using a larger sheet metal screw. Try finding a "star" washer to place under the screw head, so wont loosen up. Make sure you can't turn the wires by hand once the screw is tight.


Clean the contacts, and try using a larger sheet metal screw. Try finding a "star" washer to place under the screw head, so wont loosen up. Make sure you can't turn the wires by hand once the screw is tight.
