What are the symptoms of a bad ventilator control module?

Ventilator for a control head, that's funny.

I called the local Pontiac dealership. Their parts department confirmed the part was no longer being manufactured. However, they gave me two part numbers for the "ventilator control module"; they are 16152202 and 16152212. One includes the control for the rear window defroster, the other doesn't. Do you know what else this part might be called?

I dont think the 'climate control' is your inop. power windows problem! The ignition switch can loose it's feed to different circuits but still function on others! A simple wiggle test can confirm this, or not. That is just one possible cause of the trouble's you are having, others certainly do exist!! Suggest having a mechanic do 'more' testing before parts replacement. We hope you get it fixed and good luck!