Could not find a good answer to this problem of my climate control blower running on high even when the climate control was turned off. I found the solution through my own research. The control module went bad. This used to be called a resistor pack. Now there are no resistors in it, but only a solid state silicone FET. It is located behind the glove box. Simply open glove compartment and make it swing all the way down by squeezing in on the sides. You will see the module attached to plenum with two plugs connected. Unscrew the two 8mm screws to get module out. New part number from dealer is 5179985AA. The original module part number has been discontinued.
If you know somebody electrically inclined, they can fix the old one by replacing the power FET on circuit board.