The ign switch provides circuit 15 power to the blower regulator. And if I'm not mistaken, 15 for the main blower fuse as well. There are 2 or 3 circuit 15 outputs on the switch itself and the contact that provides power for the aac and wipers are the most common to wipe out, hence "jigglein'" the key.
Project Smoker, '87 603 powered wagon
Hauler, 96 CTD can you say torque?
Toy 73 Cougar xr7 convertible
Acme Automotive Inc.