PontiacBonnevilleClub.com

This has been going on for a few years. No fans on any setting. Only does it when it gets cold out. My hunch is that it is connected somehow to when the a/c compressor is "cut" off due to colder temps. This is cutting the fans off. Temp warms up fans work. Anyone know what I could look at that "locks out" the compressor when its too cold?

My guess is the brushes in the motor have simply warn out. Next time it doesn't turn on give it a little "love tap" you'll be able to see the motor under the dash in the passenger foot well.
BTW, your a/c compressor should be able to kick on at any temp, in the winter it comes on to defog the windows.

Worn brushes, which requires motor replacement. AC runs only when 41 degrees or above.

I agree with previous assessments - probably time for a new cabin fan motor. I don't believe there is a connection between your A/C compressor and your fan. It's possible that, in the winter, the worn commutator schnitzels really gum up the works when the temps are cold causing the armature to stick. That's just speculation, though.

Here's what happens to your fan motor from normal wear:

Thanks! Time for new motor.