Heater fan and wiring not working

[gli_ryan]

Last year my fan burnt up, stopped working and started smoking. Today I torn it down and cleaned it up and checked it out. Turns out one wire for the motor came undone off the magnet. So I put it back on and checked it a couple times and it did work.

I put the unit back in and then tried to actuate it but had no luck. Pulled it back out again and went over all the wiring, checked out good. Put it back in again after cleaning up the ground and it still won't work. While it was still in there I jumped positive to it and it started. What the hell makes these fans work? I understand the wiring, but don't understand the issue I'm having.

Insight is appreciated.

[Dave3x72tii]

turn the ignition on, and the switch to high, check for 12v at the positive motor teminal and ground at the negative. Both wires go through the box at the resistor, depending on the year, the neg or pos lead goes through the resistor except on high speed. You can check voltage at the resistor connector without removing the box to know if the fuse/wires/switch are good to the box. Heat is probably important in duluth!