02. I lost fan blower on 1,2,&3. 4&5 are fine.
 

I thought it might be a fuse but I haven't found anything blown. Any help Please. Thanks

You have a blown resistor block. It's way up under the dash on the passenger side. Above the heater box, I believe. Make sure you get the newer heavy duty version, encased in epoxy when you get one.About $35 at the dealer. Don't hold me to that. It'e been more than a few years now.

the blower resistor is behind the blower motor on the passenger side and replace it with a quality acdelco one from the dealer or somewhere that sells acdelco parts.

Thanks, I appreciate your assistance! Take care!