2000 blazer 4X4 manual HVAC I was having issues with the blower motor not running as set by the switch..I replaced the resistor and it then it ran on setting 123 but quit altogether on 4 or high. Searched around and found the underhood fuse for the HVAC was blown. Replaced the fuse and the now the bower motor runs on high and all is good there. Here's where things get interesting. With the underhood fuse for the HVAC installed the rear overhead brake light stays on, take the fuse out and the brake light goes out but the blower will not run high. If anyone has any idea why this is happening I'd appreciate the input.

 

I Found the problem and have to admit I feel just a little bit like a douche. It turned out to be the Underwood fuse for the center brake. I swear I looked in the book but didn't see it there.