For the blower motor control switch (often mistakenly called a fanac control switch), your best bets for purchasing a replacement are:
* Your local auto parts store: Places like AutoZone, Advance Auto Parts, NAPA, or O'Reilly Auto Parts will likely have it in stock or be able to order it for you. Giving them your vehicle's year, make, and model is crucial.
* Online retailers: Amazon, eBay, and RockAuto are good options. Again, be precise with your vehicle information to ensure you get the correct part. Check reviews before purchasing from online sellers, especially on eBay.
* Dealership: The Chevrolet dealership will have the correct part, but it's usually the most expensive option.
Before buying a replacement blower motor control switch, it's a good idea to verify that the switch is actually faulty. Sometimes the problem lies elsewhere in the blower motor circuit (like a blown fuse or a problem with the blower motor itself). A multimeter can help diagnose the problem.