Running all the time,yeah, that aint right. Did you add anything to the electrical system that you maybe jumped a lead from the fuse block, and tied into the fan by mistake? They usually are a higher amperage rating (25 amp fuse), therefore more enticing to tie into....
here's a picture from the electrical troubleshooting manual. I wanted to scan it, but the stupid scanner isn't working.....
Notice that the circuit is pretty strait forward. It's hot in the "run" position only. Even the blower resistor is downstream from 12v, so I wouldn't think that's bad either....
After the blower motor, it just goes to ground, so something is feeding 12vdc back through circuit #50...