My fan control and HVAC weren't working properly. I had a local shop diagnosis the problem. It was the HVAC module. The shop and the dealer wanted $800 - $1200 to fix. I found Automotive Scientific on line, and bought a new module for $349. I spent less than an hour taking out the old one and replacing with the new part. They will diagnosis your part for $55. They can rebuild the old part if it is repairable, or just buy a OEM part as I did.
Automotive Scientific Inc. | Quality Rebuilt Automotive Electronics | Rogersville, TN
They are located in Tennessee.