Check the fuses. After a while fuses become corroded and will not pass current. Also, upon occasion, they will blow out for no good reason.

Replace them, but make sure that you use CERAMIC fuses, not plastic. Plastic fuses can melt, and then look like they are making contact when they aren't.

Fuses are cheap. They are color-coded. The fusebox is under the hood, right in front of the driver.

This is the most likely solution. I am unsure of the blower, but it has a fuse all by itself I think, in a small box near the main fusebox.

If two speeds work and one does not, it probably is not a fuse.


Good luck.