2004 Pac blower won't turn off!

I just got a 2004 Pacifica AWD with all of the options, 97K miles, for $7000 on Tuesday at an auction.
Everything is perfect with the car (so far), with the exception of the thermostatic
control system. I can't get the fan to turn off! No matter what I do other than
shutting off the car, the fan runs, and it runs loud. Even if I push the power button
to off for the system, the fan turns to full on!

I'm having my mechanic hook it up to the computer on Monday (he didn't
have the right cable today).

Has anyone else had this problem?

BTW, if anyone is wondering where they can get great cars cheap, it's here in
Michigan, where the economy is the worst in the nation!

I wonder if this is the blower motor resistor?  Usually, when that goes, the fan won't come on though.

an auto temp control resistor will some times keep the fan on even if the system is off   no computer in the car will tell u whats wrong.

I think this might happen if you have the "Rear" system on.

~Dave

Thanks for your help everyone!

Dave, I also thought about the rear system and turning it off didn't help.

I had the same problem.  There was a TSB for the fan blower module being defective(or something similar -- can't remember exactly what it was called).