Originally Posted by Mxfrank

The switch in your dryer comes on when the a/c system pressure is over 300psi (may be different on some models). Normal pressures are well below this, but you can sometimes reach this high on hot humid days.

if you want to do the mod I described, get a fan switch from an 80's Jetta or Porsche, they probably have them here on Pelican. If you have trouble finding one in the temperature range you need, just ask and I can help. These have 22mm bodies, and can screw directly into any of the unused ports on the side of your head (see photo), by just removing the bung with an allen wrench. The electrical connections can be wired parallel with the switch in the receiver dryer if you want low speed (this is how mine is set up), or parallel with the switch in the engine outlet if you want high speed. Everything will still work as before, except that the fan will also come on when the jacket temperature triggers the new switch.

New Beck Arnley Engine Cooling Fan Switch Blade 201 0809 | eBay