@cUr@-TL

There is absolutely no change when I press the 'Max Defrost' button. It makes no sense for the fan to reduce its speed after driving for several minutes with the engine fully warmed up. And the whining is definitely not normal. There's no whine when the fan is working properly and I lower its speed. Plus, the problem happens after driving for a little while. At startup even if it's -20 outside and the engine is freezing cold the fan blows full blast.. I've had more issues with this truck in 6 months than I've had with my previous truck in 6 years. Not encouraging. Just yesterday, the check engine light came on. The thing is brand new... 7k miles.

Did you ever have this figured out ? My 2024 RST started doing that about 3 weeks ago. It happens almost every day now ! Even at the highest setting the fan blows like it’s set at 1/3 or something, and there’s a slight whistle… Very annoying when you are trying to defrost a frozen windshield and can’t get proper airflow !