I replaced the blower motor resistor/ controller several years ago but have had very poor air flow since. Now after reading several forums, I checked the blend door problems but they appeared fine. I could find no obstructions. The fan engaged into high.After reading on jeep garage.org... of some having the blower fan running the the wrong direction I checked and sure enough my fan was turning the wrong way. I give fault to the resistor/controller being wired wrong as when it is installed the wire clips can only go together one way. I had to cut the lead wires (green and brown I think) to the blower motor and reverse the wires. The blower now turns the correct way and air flow is restored. bygeorge