I have a 2001 BMW X5, 4.4i with 60,000 miles. I recently replaced the alternator. Two days later, I got into the car and started the engine...all was normal except that my environmental control panel indicated the AC was blowing FULL but there was no air from the vents. The compressor was working, and the rear fan was working and cooling. I removed two 7.5 amp AC fuses and they were good. The 50A main blower fuse is good. There is one interesting factor.. I pulled one of the 7.5A ac fuses with engine running to verify it was correct fuse (compressor stopped) and when I replaced it the main fan started working. However, when I moved the car it stopped. It came back on once about 30 seconds later then stopped. Do you have any ideas about this issuue? Thanks JP

the problem you describe is the final stage unit for the a/c blower has failed.reinstall all the fuses and replace the final stage unit,it is located in the passenger footwell area on the right side of the "heater box" (the plastic housing that contains the heat exchangers)

I've also got a 2001 X5 4.4i with a similar issue. Be advised that my wiring harness in the passenger side foot well has shorted out and melted causing loss of power to the fan blower motor. This might be your problem too!

I have seen the final stage wiring harness fail on a couple of X5. melted at the connector to the final stage