BMW Repair: intermittent ac fan, airduct, cable connector

Question
I noticed that after pulling my 528iT 2003 into the garage and turning off the car the dash fan would come on for a couple of seconds and go off.  This repeated itself about every 60 sec or so.  Today this happened while driving.  With the fan turned off it would cycle on for a couple of sec and do this every minute or two.  Is this normal?
Thanks very much,

Answer
Hi Jeff,
I am 99% certain that it is a defective AC final stage.
While it is not impossible for a non-mechanic to replace it,
it is quite a pain. It is located at the passenger's side
center console front end almost right at the wall before the engine compartment. You have to remove the right lower dashboard cover (sometimes including the glovebox). Also remove any trim cover at right side of console box end.
If need be, detach the lower airduct. Once you have the part on hand, and the impediments removed, all you need is a little patience and pulling to get it out(of course after detaching the cable connector first). Sometimes it is
screwed on, oftentimes it is just held in place by a little
plastic lock/clamp. Have fun!
Tino